WO2016187028A1

WO2016187028A1 - Heteroaryl compounds, synthesis thereof, and intermediates thereto

Info

Publication number: WO2016187028A1
Application number: PCT/US2016/032422
Authority: WO
Inventors: Paul Frank FERNANDEZ; Antonio Christian Ferretti; Jianxin HAN; John Traverse; Hsien-Hsin Tung; Kelvin Hin-Yeong Yong; Nanfei Zou
Original assignee: Celgene Avilomics Research, Inc.
Priority date: 2015-05-15
Filing date: 2016-05-13
Publication date: 2016-11-24

Abstract

The present invention relates to methods for synthesizing compounds useful as inhibitors or both of ERK1 and ERK2 kinase, derivatives thereof, and intermediates thereto.

Description

HETEROARYL COMPOUNDS, SYNTHESIS THEREOF, AND INTERMEDIATES

THERETO

CROSS-REFERENCE TO RELATED APPLICATIONS

[0001] The present application claims priority to U.S. provisional application number 62/162,218, filed May 15, 2015, the entirety of which is hereby incorporated by reference.

FIELD OF THE INVENTION

[0002] The present invention relates to methods for synthesizing compounds useful as inhibitors of ERK kinases, for example one or both of ERK1 and ERK2 kinases.

BACKGROUND OF THE INVENTION

[0003] The search for new therapeutic agents has been greatly aided in recent years by a better understanding of the structure of enzymes and other biomolecules associated with diseases. One important class of enzymes that has been the subject of extensive study is protein kinases.

[0004] Protein kinases constitute a large family of structurally related enzymes that are responsible for the control of a variety of signal transduction processes within the cell. Protein kinases are thought to have evolved from a common ancestral gene due to the conservation of their structure and catalytic function. Almost all kinases contain a similar 250-300 amino acid catalytic domain. The kinases may be categorized into families by the substrates they phosphorylate (e.g., protein-tyrosine, protein-serine/threonine, lipids, etc.).

[0005] The processes involved in tumor growth, progression, and metastasis are mediated by signaling pathways that are activated in cancer cells. The ERK pathway plays a central role in regulating mammalian cell growth by relaying extracellular signals from ligand-bound cell surface tyrosine kinase receptors such as erbB family, PDGF, FGF, and VEGF receptor tyrosine kinase. Activation of the ERK pathway is via a cascade of phosphorylation events that begins with activation of Ras. Activation of Ras leads to the recruitment and activation of Raf, a serine- threonine kinase. Activated Raf then phosphorylates and activates MEKl/2, which then phosphorylates and activates one or both of ERK1 and ERK2. When activated, one or both of ERKl and ERK2 phosphorylates several downstream targets involved in a multitude of cellular

1 events including cytoskeletal changes and transcriptional activation. The ERK/MAPK pathway is one of the most important for cell proliferation, and it is believed that the ERK/MAPK pathway is frequently activated in many tumors. Ras genes, which are upstream of one or both of ERKl and ERK2, are mutated in several cancers including colorectal, melanoma, breast and pancreatic tumors. The high Ras activity is accompanied by elevated ERK activity in many human tumors. In addition, mutations of BRAF, a serine-threonine kinase of the Raf family, are associated with increased kinase activity. Mutations in BRAF have been identified in melanomas (60%), thyroid cancers (greater than 40%) and colorectal cancers.

[0006] Many diseases are associated with abnormal cellular responses triggered by protein kinase-mediated events as described above. Accordingly, there remains a need to find protein kinase inhibitors useful as therapeutic agents.

SUMMARY OF THE INVENTION

[0007] As described herein, the present invention provides methods for preparing compounds useful as inhibitors of ERK kinases, for example one or both of ERKl and ERK2. Such compounds include Compound I:

or a pharmaceutically acceptable salt thereof.

[0008] Compound I, and pharmaceutically acceptable salts thereof, are useful for treating a variety of diseases, disorders or conditions, associated with abnormal cellular responses triggered by certain protein kinase-mediated events. Such diseases, disorders, or conditions include those described herein.

[0009] Compound I, and pharmaceutically acceptable salts thereof, are also useful for the study of certain kinases in biological and pathological phenomena; the study of intracellular signal transduction pathways mediated by such kinases; and the comparative evaluation of new kinase inhibitors. Additional such compounds and methods can be found in PCT application publication number WO2014/124230, published August 14, 2014 ("the '230 publication," the entirety of which is hereby incorporated herein by reference). The '230 publication describes certain ERK inhibitor compounds which covalently and irreversibly inhibit activity of one or both of ERK 1 and ERK2 kinases.

[0010] The present invention also provides synthetic intermediates useful for preparing such compounds.

BRIEF DESCRIPTION OF THE DRAWINGS

[0011] Figure 1 depicts an XRPD pattern of Form A of compound 7.

[0012] Figure 2 depicts a DSC thermogram of Form A of compound 7.

[0013] Figure 3 depicts a an XRPD pattern of Form A of compound 8.

[0014] Figure 4 depicts a DSC thermogram of Form A of compound 8.

[0015] Figure 5 depicts a an XRPD pattern of Form A of compound 9.

[0016] Figure 6 depicts a DSC thermogram of Form A of compound 9.

[0017] Figure 7 depicts an XRPD pattern of Form B of compound 9.

[0018] Figure 8 depicts a DSC thermogram of Form B of compound 9.

[0019] Figure 9 depicts an XRPD pattern of Form A of a phosphate salt of Compound I.

[0020] Figure 10 depicts a DSC thermogram of Form A of a phosphate salt of Compound I.

[0021] Figure 11 depicts a TGA trace of Form A of a phosphate salt of Compound I.

[0022] Figure 12 depicts a DVS plot of Form A of a phosphate salt of Compound I.

[0023] Figure 13 depicts PLM images of crystals of the phosphate salt of Compound I at different stages of a crystallization process comprising ten heat-cool cycles performed on an initial portion (20% of the total final mass) of free base Compound I with an initial portion (20%) of the total phosphoric acid (1.2 mol. equiv. relative to free base Compound I).

[0024] Figure 14 depicts PLM images of crystals of the phosphate salt of Compound I at different stages of a crystallization process comprising ten heat-cool cycles performed on an entire batch (100% of the total final mass) of free base Compound I with an initial portion (20%) of the total phosphoric acid (1.2 mol. equiv. relative to free base Compound I). DEFINITIONS

[0025] Compounds of this invention include those described generally above, and are further illustrated by the classes, subclasses, and species disclosed herein. As used herein, the following definitions shall apply unless otherwise indicated. For purposes of this invention, the chemical elements are identified in accordance with the Periodic Table of the Elements, CAS version, Handbook of Chemistry and Physics, 75^th Ed. Additionally, general principles of organic chemistry are described in "Organic Chemistry", Thomas Sorrell, University Science Books, Sausalito: 1999, and "March's Advanced Organic Chemistry", 5^th Ed., Ed.: Smith, M B. and March, J., John Wiley & Sons, New York: 2001, the entire contents of which are hereby incorporated by reference.

[0026] As used herein, the term "pharmaceutically acceptable salt" refers to those salts which are, within the scope of sound medical judgment, suitable for use in contact with the tissues of humans and lower animals without undue toxicity, irritation, allergic response and the like, and are commensurate with a reasonable benefit/risk ratio. Pharmaceutically acceptable salts are well known in the art. For example, S. M. Berge et al., describe pharmaceutically acceptable salts in detail in J. Pharmaceutical Sciences, 1977, 66, 1-19, incorporated herein by reference. Pharmaceutically acceptable salts of the compounds of this invention include those derived from suitable inorganic and organic acids and bases. Examples of pharmaceutically acceptable, nontoxic acid addition salts are salts of an amino group formed with inorganic acids such as hydrochloric acid, hydrobromic acid, phosphoric acid, sulfuric acid and perchloric acid or with organic acids such as acetic acid, oxalic acid, maleic acid, tartaric acid, citric acid, succinic acid or malonic acid or by using other methods used in the art such as ion exchange. Other pharmaceutically acceptable salts include adipate, alginate, ascorbate, aspartate, benzenesulfonate, benzoate, bisulfate, borate, butyrate, camphorate, camphorsulfonate, citrate, cyclopentanepropionate, digluconate, dodecylsulfate, ethanesulfonate, formate, fumarate, glucoheptonate, glycerophosphate, gluconate, hemisulfate, heptanoate, hexanoate, hydroiodide, 2-hydroxy-ethanesulfonate, lactobionate, lactate, laurate, lauryl sulfate, malate, maleate, malonate, methanesulfonate, 2-naphthalenesulfonate, nicotinate, nitrate, oleate, oxalate, palmitate, pamoate, pectinate, persulfate, 3-phenylpropionate, phosphate, pivalate, propionate, stearate, succinate, sulfate, tartrate, thiocyanate, p-toluenesulfonate, undecanoate, valerate salts, and the like. [0027] Salts derived from appropriate bases include alkali metal, alkaline earth metal, ammonium and N⁺(Ci^alkyl)₄ salts. Representative alkali or alkaline earth metal salts include sodium, lithium, potassium, calcium, magnesium, and the like. Further pharmaceutically acceptable salts include, when appropriate, nontoxic ammonium, quaternary ammonium, and amine cations formed using counterions such as halide, hydroxide, carboxylate, sulfate, phosphate, nitrate, loweralkyl sulfonate and aryl sulfonate.

[0028] Unless otherwise stated, structures depicted herein are also meant to include all isomeric (e.g., enantiomeric, diastereomeric, and geometric (or conformational)) forms of the structure; for example, the (R) and (S) configurations for each asymmetric center, (Z) and (E) double bond isomers, and (Z) and (E) conformational isomers. Therefore, single stereochemical isomers as well as enantiomeric, diastereomeric, and geometric (or conformational) mixtures of the present compounds are within the scope of the invention. Unless otherwise stated, all tautomeric forms of the compounds of the invention are within the scope of the invention.

[0029] As used herein, the term "inhibitor" is defined as a compound that binds to and /or inhibits the target protein kinase with measurable affinity. In certain embodiments, an inhibitor has an IC₅₀ and/or binding constant of less about 50 μΜ, less than about 1 μΜ, less than about 500 nM, less than about 100 nM, or less than about 10 nM.

DETAILED DESCRIPTION OF THE INVENTION

Methods of Making Compound I

[0030] In some embodiments, Compound I, or a pharmaceutically acceptable salt thereof, is prepared according to Scheme I set forth below:

Scheme I

[0031] In Scheme I above, each of LG¹, LG², and PG¹ is as defined below and in classes and subclasses described herein.

[0032] In some embodiments, Compound I, or a pharmaceutically acceptable salt thereof, is prepared according to Scheme I' set forth below:

[0033] In Scheme I' above, each of LG¹, LG², LG³, LG⁴, and PG¹ is as defined below and in classes and subclasses described herein. One of skill in the art will recognize that Scheme I' differs from Scheme I in that Scheme I' provides an alternative route to a compound of Formula E, i.e., via step S--1' using as starting material a compound of formula G, described in further detail below. Accordingly, embodiments described below and herein for steps S-2 through S-5 are contemplated as occurring in the context of each of Scheme I and Scheme I'.

Step S-1 of Scheme I

[0034] At step S-1 of Scheme I, the amine group of commercially available compound F is protected to afford a compound of formula E.

[0035] The PG¹ group of a compound of formula E is a suitable amino protecting group. One of skill in the art would appreciate that various methods and conditions for protecting amines are known in the chemical arts. For example, suitable amino protecting groups are well known in the art and include those described in detail in Protecting Groups in Organic Synthesis, T. W. Greene and P. G. M. Wuts, 3^rd edition, John Wiley & Sons, 1999, the entirety of which is incorporated herein by reference. Suitable amino protecting groups, taken with the -NH- moiety to which it is attached, include, but are not limited to, aralkylamines, carbamates, allyl amines, amides, and the like. Examples of PG¹ groups of a compound of formula E include t- butyloxycarbonyl (BOC), p-methoxybenzyloxycarbonyl (PMB), ethyloxycarbonyl, methyloxycarbonyl, trichloroethyloxycarbonyl, allyloxycarbonyl (Alloc), benzyl oxocarbonyl (CBZ), allyl, benzyl (Bn), fluorenylmethylcarbonyl (Fmoc), acetyl, chloroacetyl, dichloroacetyl, trichloroacetyl, phenylacetyl, trifluoroacetyl, benzoyl, and the like. In some embodiments, the PG¹ group of a compound of formula E is t-butyloxycarbonyl (BOC). In certain embodiments, the PG¹ group of a compound of formula E is BOC and the protecting group reagent used to generate PG¹ is di-tert-butyl dicarbonate.

[0036] In some embodiments, step S-1 requires an amount of protecting group reagent of about 1.0 molar equivalents or less relative to substrate. For instance, in some embodiments, step S-1 requires an amount of protecting group reagent (e.g., di-tert-butyl dicarbonate) of about 0.1, 0.2, 0.3, 0.4, 0.5, 0.6, 0.7, 0.8, 0.85, 0.9, 0.95, 0.96, 0.97, 0.98, or 0.99 molar equivalents relative to substrate. In some embodiments, step S-1 requires an amount of protecting group reagent of about 1.0 to about 2.0 molar equivalents relative to substrate. For instance, in some embodiments, step S-1 requires an amount of protecting group reagent (e.g., di-tert-butyl dicarbonate) of about 1.0, 1.1, 1.2, 1.3, 1.4, 1.5, 1.6, 1.7, 1.8, 1.9, or 2.0 molar equivalents relative to substrate. In certain embodiments, the protecting group reagent is di-tert-butyl dicarbonate and is present in an amount of about 1.0 to about 2.0 molar equivalents relative to substrate. In certain embodiments, the protecting group reagent is di-tert-butyl dicarbonate and is present in an amount of about 1.1 molar equivalents relative to substrate. In certain embodiments, the protecting group reagent is di-tert-butyl dicarbonate and is present in an amount of about 1.2 molar equivalents relative to substrate. In certain embodiments, the protecting group reagent is di-tert-butyl dicarbonate and is present in an amount of about 1.3 molar equivalents relative to substrate.

[0037] In some embodiments, step S-1 is conducted in a solvent comprising an organic solvent. In some embodiments, step S-1 is conducted in a solvent comprising a polar aprotic solvent. In some embodiments, step S-1 is conducted in a solvent comprising an ethereal solvent. In some embodiments, step S-1 is conducted in a solvent comprising an ethereal solvent such as an optionally substituted tetrahydrofuran or a dialkylether. In certain embodiments, step S-1 is conducted in a solvent comprising a substituted tetrahydrofuran such as, e.g., 2- methyltetrahydrofuran (2-MeTHF). In some embodiments, step S-1 is conducted in a solvent comprising tetrahydrofuran (THF). In some embodiments, step S-1 is conducted in a solvent comprising a dialkylether (e.g., diethylether). In some embodiments, step S-1 is conducted in a solvent comprising a single organic solvent. In some embodiments, step S-1 is conducted in a solvent comprising a combination of organic solvents. In certain embodiments, step S-1 is conducted in 2-MeTHF.

[0038] In other embodiments, step S-1 is conducted the presence of a base.

[0039] In some embodiments, a base is an organic base. In some embodiments, a base is an amine base (e.g., trimethylamine). In some embodiments, a base is an inorganic base. In some embodiments, an inorganic base is an alkali hydroxide. In some embodiments, an inorganic base is LiOH. In some embodiments, an inorganic base is NaOH. In some embodiments, an inorganic base is KOH. In some embodiments, a base a carbonate. In some embodiments, a base is Na₂CO₃. In some embodiments, a base is K₂CO₃. In some embodiments, a base a bicarbonate. In some embodiments, a base is NaHCO₃. In some embodiments, a base is KHCO₃. In some embodiments, a base is a phosphate. In some embodiments, a base is Na₃PO₄. In some embodiments, a base is K₃PO₄. In some embodiments, a base is phosphate dibasic. In some embodiments, a base is K₂HPO₄.

[0040] In some embodiments, step S-1 is conducted the presence of a base and di-tert-butyl dicarbonate is the protecting group reagent.

[0041] In some embodiments, step S-1 is conducted in the presence of a hydroxide base (e.g., NaOH) in a suitable solvent (e.g., an ether such as 2-MeTHF) and di-tert-butyl dicarbonate is the protecting group reagent. In some such embodiments, di-tert-butyl dicarbonate is present in an amount of about 1.7 equivalents relative to substrate. In some such embodiments, the solvent (e.g., an ether such as 2-MeTHF) is present in a volume of about IX.

[0042] In some embodiments, step S-1 is conducted in the presence of an amine base (e.g., trimethylamine) and a nucleophilic catalyst (e.g., DMAP) in a suitable solvent (e.g., an ether such as THF) and di-tert-butyl dicarbonate is the protecting group reagent. In some such embodiments, step S-1 is conducted at a temperature of about 20 °C to about 30 °C. In some such embodiments, step S-1 is conducted at a temperature of about 25 °C. [0043] In some embodiments, step S-1 is conducted in the presence of a hydroxide base (e.g., NaOH) in a suitable solvent (e.g., a mixture of an ether such as THF and water) and di-tert-butyl dicarbonate is the protecting group reagent. In some such embodiments, step S-1 is conducted at a temperature of about 20 °C to about 30 °C. In some such embodiments, step S-1 is conducted at a temperature of about 25 °C.

[0044] In some embodiments, step S-1 is conducted in the presence of a hydroxide base (e.g., NaOH) in an amount of about 0.1 equivalents relative to substrate, in the presence of an excess of protecting group reagent (e.g., 3 equivalents of di-tert-butyl dicarbonate relative to substrate) in a suitable solvent (e.g., a solvent comprising THF). In some such embodiments, step S-1 is conducted at a temperature of about 40 °C to about 60 °C. In some such embodiments, step S-1 is conducted at a temperature of about 50 °C.

[0045] In some embodiments, step S-1 is conducted in the presence of a hydroxide base (e.g., NaOH) in an amount of about 0.1 equivalents relative to substrate, in the presence of an excess of protecting group reagent (e.g., 4 equivalents of di-tert-butyl dicarbonate relative to substrate) in a suitable solvent (e.g., a solvent comprising THF). In some such embodiments, step S-1 is conducted at a temperature of about 45 °C to about 65 °C. In some such embodiments, step S-1 is conducted at a temperature of about 55 °C.

[0046] In some embodiments, step S-1 is conducted in the presence of a hydroxide base (e.g., NaOH) in an amount of about 0.1 equivalents relative to substrate, in the presence of an excess of protecting group reagent (e.g., 3 equivalents of di-tert-butyl dicarbonate relative to substrate) in a suitable solvent (e.g., a solvent comprising acetonitrile). In some such embodiments, step S- 1 is conducted at a temperature of about 60 °C to about 80 °C. In some such embodiments, step S-1 is conducted at a temperature of about 70 °C.

[0047] In some embodiments, step S-1 is conducted in the presence of a hydroxide base (e.g., NaOH) in an amount of about 0.1 equivalents relative to substrate, in the presence of an excess of protecting group reagent (e.g., 3 equivalents of di-tert-butyl dicarbonate relative to substrate) in a suitable solvent (e.g., a solvent comprising an ether such as 2-MeTHF). In some such embodiments, step S-1 is conducted at a temperature of about 60 °C to about 80 °C. In some such embodiments, step S-1 is conducted at a temperature of about 70 °C.

[0048] In some embodiments, step S-1 is conducted in the presence of aqueous hydroxide base (e.g., 10N aqueous NaOH (5 mol%)) in the presence of an excess of protecting group reagent (e.g., 2 equivalents of di-tert-butyl dicarbonate relative to substrate) in a suitable solvent (e.g., 3X volume 2-MeTHF). In some such embodiments, step S-1 is conducted at a temperature of about 70 °C to about 90 °C. In some such embodiments, step S-1 is conducted at a temperature of about 78 °C. In some such embodiments, the reaction is run for about 30 to 40 hours. In some such embodiments, the reaction is run for about 35 hours. In some such embodiments, additional protecting group reagent is optionally charged as required to improve yields. In some such embodiments, the protecting group reagent (e.g., di-tert-butyl dicarbonate) is dissolved in a suitable solvent (e.g., an ether such as 2-MeTHF) and added to the substrate over an amount of time suitable to minimize pressure build up within the reaction vessel.

[0049] In some embodiments, step S-1 is conducted in the presence of a hydroxide base (e.g., NaOH) in an amount of about 0.05 equivalents relative to substrate, in a suitable solvent (e.g., an ether such as 2-MeTHF), wherein the solvent is present in a volume between about IX and 3X. In some such embodiments, the protecting group reagent is di-tert-butyl dicarbonate and is present in an amount of about 1.0 to 1.5 equivalents relative to substrate. In certain embodiments, the solvent is present in a volume of about IX. In certain embodiments, the solvent is present in a volume of about 2X. In certain embodiments, the solvent is present in a volume of about 3X.

[0050] In some embodiments, step S-1 is conducted in the presence of a hydroxide base (e.g., NaOH) in an amount of about 0.1 equivalents relative to substrate, in a suitable solvent (e.g., an ether such as 2-MeTHF), wherein the solvent is present in a volume between about IX and 3X. In some such embodiments, the protecting group reagent is di-tert-butyl dicarbonate and is present in an amount of about 1.0 to 1.5 equivalents relative to substrate. In certain embodiments, the solvent is present in a volume of about IX. In certain embodiments, the solvent is present in a volume of about 2X. In certain embodiments, the solvent is present in a volume of about 3X.

[0051] In some embodiments, step S-1 is conducted in the presence of a hydroxide base (e.g., NaOH) in an amount of about 0.05 equivalents relative to substrate, in about IX volume of suitable solvent (e.g., an ether such as 2-MeTHF), with about 1.25 equivalents of protecting group reagent (e.g., di-tert-butyl dicarbonate).

[0052] In some embodiments, step S-1 is conducted in the presence of a hydroxide base (e.g., NaOH) in an amount of about 0.1 equivalents relative to substrate, in about IX volume of suitable solvent (e.g., an ether such as 2-MeTHF), with about 1.5 equivalents of protecting group reagent (e.g., di-tert-butyl dicarbonate).

[0053] In some embodiments, step S-1 is conducted in the presence of a hydroxide base (e.g., NaOH) in an amount of about 0.1 equivalents relative to substrate, in about IX volume of suitable solvent (e.g., an ether such as 2-MeTHF), with about 1.0 equivalents of protecting group reagent (e.g., di-tert-butyl dicarbonate).

[0054] In some embodiments, step S-1 is conducted in the presence of a hydroxide base (e.g., NaOH) in an amount of about 0.05 equivalents relative to substrate, in about IX volume of suitable solvent (e.g., an ether such as 2-MeTHF), with about 1.25 equivalents of protecting group reagent (e.g., di-tert-butyl dicarbonate).

[0055] In some embodiments, the rate of conversion of step S-1 is determined in part by the relative amounts of base versus protecting group reagent present. For instance, in some embodiments wherein reactions are run with higher amounts of protecting group reagent (e.g., >1.3 equivalents of di-tert-butyl dicarbonate) and lower amounts of base (e.g., about 0.05 equivalents of NaOH) at least 70% conversion is achieved after about 8 hours. In some embodiments, wherein reactions are run with higher amounts of protecting group reagent (e.g., >1.3 equivalents of di-tert-butyl dicarbonate) and higher amounts of base (e.g., > 0.5 equivalents of NaOH), or wherein reactions are run with lower amounts of protecting group reagent (e.g., 1.3 equivalents of di-tert-butyl dicarbonate or less) and lower amounts of base (e.g., 0.5 equivalents of NaOH or less) at least 80% conversion is achieved after 24 hours.

[0056] In some embodiments, step S-1 is conducted in the absence of a base.

[0057] In some embodiments, step S-1 is conducted the absence of a base and di-tert-butyl dicarbonate is the protecting group reagent.

[0058] In some embodiments, step S-1 is conducted in the presence of a nucleophilic catalyst (e.g., DMAP) in a suitable solvent (e.g., a solvent comprising acetonitrile) and di-tert-butyl dicarbonate is the protecting group reagent. In some such embodiments, step S-1 is conducted at a temperature of about 40 °C to about 70 °C. In some such embodiments, step S-1 is conducted at a temperature of about 50 °C to about 60 °C.

[0059] In some embodiments, step S-1 is conducted in a suitable solvent (e.g., a mixture of an ether such as THF and water) and di-tert-butyl dicarbonate is the protecting group reagent. In some such embodiments, step S-1 is conducted at a temperature of about 40 °C to about 60 °C.

In some such embodiments, step S-1 is conducted at a temperature of about 50 °C.

[0060] In some embodiments, step S-1 is conducted in a suitable solvent (e.g., an ether such as 2-MeTHF), wherein the solvent is present in a volume between about IX and 3X, and di-tert- butyl dicarbonate is the protecting group reagent. In certain embodiments, the solvent is present in a volume of about IX. In certain embodiments, the solvent is present in a volume of about

2X. In certain embodiments, the solvent is present in a volume of about 3X.

[0061] In some embodiments, step S-1 is conducted in a suitable solvent (e.g., an ether such as 2-MeTHF), wherein the solvent is present in a volume of about IX and di-tert-butyl dicarbonate is present in an amount of about 1.0 equivalents relative to substrate.

[0062] In some embodiments, step S-1 is conducted in a suitable solvent (e.g., an ether such as 2-MeTHF), wherein the solvent is present in a volume of about IX and di-tert-butyl dicarbonate is present in an amount of about 1.1 equivalents relative to substrate.

[0063] In some embodiments, step S-1 is conducted in a suitable solvent (e.g., an ether such as 2-MeTHF), wherein the solvent is present in a volume of about IX and di-tert-butyl dicarbonate is present in an amount of about 1.2 equivalents relative to substrate.

[0064] In some embodiments, step S-1 is conducted in a suitable solvent (e.g., an ether such as 2-MeTHF), wherein the solvent is present in a volume of about IX and di-tert-butyl dicarbonate is present in an amount of about 1.3 equivalents relative to substrate.

[0065] In some embodiments, step S-1 is conducted in a suitable solvent (e.g., an ether such as 2-MeTHF), wherein the solvent is present in a volume of about IX and di-tert-butyl dicarbonate is present in an amount of about 1.4 equivalents relative to substrate.

[0066] In some embodiments, step S-1 is conducted in a suitable solvent (e.g., an ether such as 2-MeTHF), wherein the solvent is present in a volume of about IX and di-tert-butyl dicarbonate is present in an amount of about 1.5 equivalents relative to substrate.

[0067] In some embodiments, step S-1 is conducted at elevated temperatures. For instance, in some embodiments, step S-1 is conducted at a temperature between about 50 °C and about 100

°C. In some embodiments, the temperature is between about 55 °C and about 95 °C. In some embodiments, the temperature is between about 60 °C and about 90 °C. In certain embodiments, the reaction is conducted at about 70 °C. In certain embodiments, the reaction is conducted at about 75 °C. In certain embodiments, the reaction is conducted at about 80 °C. In certain embodiments, the reaction is conducted at about 85 °C.

[0068] In some embodiments, the protecting group reagent of step S-1 (e.g., di-tert-butyl dicarbonate) is dissolved in a suitable solvent (e.g., 2-MeTHF) prior to addition to the reaction mixture. In some embodiments, the dissolved protecting group reagent (e.g., di-tert-butyl dicarbonate in 2-MeTHF) is added to the reaction mixture over a period of time. In some embodiments, addition occurs over a period of time while the reaction mixture is held at an elevated temperature. For instance, in some embodiments, addition to the reaction mixture occurs at an elevated temperature for about 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, or 24 hours. In some embodiments, addition to the reaction mixture occurs at an elevated temperature for about 10-24 hours. In some embodiments, addition to the reaction mixture occurs at an elevated temperature for about 10-22 hours. In some embodiments, addition to the reaction mixture occurs at an elevated temperature for about 12-22 hours. In some embodiments, addition to the reaction mixture occurs at an elevated temperature for about 12-16 hours.

[0069] In some embodiments, the reaction is allowed to run for an additional amount of time after the protecting group reagent has been added. For instance, in some embodiments, the reaction is allowed to run for about 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, or 16 more hours. In some embodiments, the reaction is allowed to run for about 6 more hours. In some embodiments, the reaction is allowed to run for about 12 more hours.

[0070] In some embodiments, after the reaction has run for a period of time, an additional amount of dissolved protecting group reagent is added in portions to the reaction mixture until a desired level of conversion is achieved. In some embodiments, once a desired level of conversion is achieved, the reaction is allowed to cool (e.g., to between about 20 °C to about 30 °C) and an amount of water and an organic solvent (e.g., 2-MeTHF) is added to it, followed by extraction of the organic layer. In some embodiments, the organic layer is washed with water. In some embodiments, the organic layer is washed with water 1, 2, 3, 4, or 5 times.

[0071] In some embodiments, it is desirable to remove residual water or solvent from the product. In certain embodiments, removal of water occurs azeotropically by distilling (for instance using continuous vacuum distillation) a solution of the product compound and an appropriate organic solvent. In certain embodiments, the process of distilling off an amount of solvent (e.g., 2-MeTHF) is continued until the water content of the product solution is reduced to a desired level.

[0072] In some embodiments, a second, continuous vacuum distillation is performed using an organic solvent such as an alkane. For instance, in some embodiments, an organic solvent is an alkane such as a hexane or a heptane. In certain embodiments, continuous vacuum distillation is performed until the solution comprises a desired solvent composition. For instance, in some embodiments, a first distillation is performed to remove solvents used during work-up, followed by a second, continuous distillation with, e.g., n-heptane, wherein the second, continuous distillation proceeds until the solvent composition or volume reaches a desired level.

[0073] For instance, in some embodiments, a product solution undergoes a first distillation with, e.g., 2-MeTHF, and a second distillation with, e.g., n-heptane, wherein the second distillation proceeds until the amount of 2-MeTHF present in the distilled product solution is no more than about 10%, 9%, 8%, 7%, 6%, 5%, 4%, 3%, 2%, or 1% (v/v).

[0074] In some embodiments, a crystallization is performed. In some embodiments, the above-described distillations are performed prior to crystallization. In some embodiments, the solution containing the product compound is cooled to a desired temperature prior to crystallization. In certain embodiments the solution containing the product compound is cooled to about 40 °C, 45 °C, 50 °C, or 55 °C. In certain embodiments the solution containing the product compound is cooled to about 40 °C to about 50 °C.

[0075] In some embodiments, crystallization of the solution containing the product compound is initiated by adding seed crystals. For instance, in some embodiments, seeding occurs with a particular polymorph of a compound of formula E. Exemplary such polymorphs are contemplated further below.

[0076] In some embodiments, crystallization comprises a step of agitating for an amount of time. For instance, in some embodiments, agitation lasts for about 5, 10, 15, 20, 25, 30, 35, 40, 45, 50, 55, 60, 65, 70, 75, 80, 85, 90, 95, 100, 105, 110, 115, or 120 minutes. In certain embodiments, agitation lasts for between about 45 minutes and about 65 minutes. In certain embodiments, agitation lasts for about 60 minutes.

[0077] In some embodiments, crystallization comprises a step of cooling the agitated solution over a period of time. For instance, in some embodiments, the solution is cooled to between about -10 °C and about 10 °C. In some embodiments, the solution is cooled to between about -5 °C and about 10 °C. In some embodiments, the solution is cooled to between about -5 °C and about 5 °C. In some embodiments, the solution is cooled to between about 0 °C and about 10 °C. In some embodiments, cooling takes place over an amount of time, for instance, about 1, 2, 3, 4, 5, or 6 hours. In certain embodiments, a solution is cooled for about 2 hours. In certain embodiments, a solution is cooled for about 3 hours. In certain embodiments, a solution is cooled for about 4 hours. In certain embodiments, a solution is cooled for about 5 hours.

[0078] In some embodiments, crystallization comprises a step of agitating the cooled solution. In some embodiments, the cooled solution is agitated for about 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, or 24 hours. In certain embodiments, the cooled solution is agitated for about 16 hours.

[0079] In some embodiments, the cooled solution is allowed to stand for about 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, or 24 hours. In certain embodiments, the cooled solution is allowed to stand for about 16 hours.

[0080] In some embodiments, upon completion of crystallization, the resulting product is filtered, washed with an amount of solvent (e.g., an alkane such as n-heptane), and dried.

Step S-l ' o f Scheme Γ

[0081] In some embodiments, the present invention provides an alternative route to a compound of formula E wherein PG¹ of formula E is a BOC protecting group (i.e., Compound 7, depicted below). For instance, at step S-1' of Scheme I', depicted above, a compound of formula G is functionalized in a two-step process by first performing a methoxylation (i.e., step (a) of step S-1'), followed by amination (i.e., step (b) of step S-1') to afford a compound of formula E.

[0082] Each of LG³ and LG⁴ of a compound of formula G is a suitable leaving group subject to displacement. In some embodiments, each of LG³ and LG⁴ is a halogen.

[0083] In some embodiments, LG³ is halogen. In some embodiments, LG³ is -CI. In some embodiments, LG³ is -Br. In some embodiments, LG³ is -I.

[0084] In some embodiments, LG⁴ is halogen. In some embodiments, LG⁴ is -CI. In some embodiments, LG⁴ is -Br. In some embodiments, LG⁴ is -I.

[0085] In some embodiments, each of LG³ and LG⁴ is independently halogen. In some embodiments, each of LG³ and LG⁴ is -CI. [0086] In some embodiments, a compound of formula G is compound 10:

[0087] In some embodiments, step (a) of step S-1 is conducted in a solvent comprising an organic solvent. In some embodiments, step (a) of step S-1 is conducted in a solvent comprising an aromatic solvent. For instance, in some embodiments, step (a) of step S-1 is conducted in a solvent comprising benzene, toluene, or xylene. In certain embodiments, step (a) of step S-1 is conducted in a solvent comprising toluene.

[0088] In some embodiments, step (a) of step S-1 is conducted the presence of a base. In some embodiments, a base is an inorganic base. In some embodiments, an inorganic base is an alkali methoxide. In some embodiments, an inorganic base is LiOMe. In some embodiments, an inorganic base is NaOMe. In some embodiments, an inorganic base is KOMe. In some embodiments, an inorganic base is CsOMe.

[0089] In some embodiments, step (a) of step S-1 comprises a first step of heating a mixture of base (e.g., NaOMe) and solvent (e.g., toluene) at elevated temperatures. In some embodiments, an elevated temperature is about 60 °C to about 120 °C. In some embodiments, an elevated temperature is about 70 °C to about 110 °C. In some embodiments, an elevated temperature is about 80 °C to about 100 °C. In some embodiments, an elevated temperature is about 85 °C to about 95 °C. In some embodiments, an elevated temperature is about 90 °C. In some embodiments, an amount of solvent (e.g., toluene) is distilled under reduced pressure after heating for an amount of time in order to reduce the reaction volume prior to cooling. In some embodiments, no distillation is performed prior to cooling. In some embodiments, once the reaction vessel has been cooled for an amount of time a compound of formula G is added, followed by an organic solvent rinse (e.g., a toluene rinse). In some embodiments, the temperature is then raised to between about 80 °C and about 120 °C, or between about 90 °C and about 110 °C, or between about 85 °C and about 110 °C, or between about 90 °C and about 110 °C, or between about 95 °C and about 110 °C, or between about 100 °C and about 110 °C. In some embodiments, the temperature is raised to about 100 °C, 101 °C, 102 °C, 103 °C, 104 °C, 105 °C, 106 °C, 107 °C, 108 °C, 109 °C, or 110 °C. In certain embodiments, the temperature is raised to about 104 °C.

[0090] In some embodiments, the reaction is held at an elevated temperature for about 24 hours to about 48 hours. In some embodiments, the reaction is held at an elevated temperature for about 28 hours to about 44 hours. In some embodiments, the reaction is held at an elevated temperature for about 32 hours to about 40 hours. In some embodiments, the reaction is held at an elevated temperature for about 34 hours to about 38 hours. In some embodiments, the reaction is held at an elevated temperature for about 36 hours.

[0091] Upon completion of step (a) of step S-1 , the reaction is cooled for an amount of time. In some embodiments, the reaction is cooled to between about 20 °C to about 30 °C. In some embodiments, the reaction is cooled to about 25 °C.

[0092] In some embodiments, upon completion of step (a) of step S-1 , the reaction solution is washed one or more times with water. In certain embodiments, the reaction solution is washed at least twice with water. In certain embodiments, the reaction solution is washed at least three times with water.

[0093] In some embodiments, the reaction solution is washed with an aqueous acid solution. For instance, in some embodiments, the reaction solution is washed with about 10% to about 15% aqueous acid. In some embodiments, the acid is citric acid. In some embodiments, the acid is acetic acid. In some embodiments, the acid is phosphoric acid. In some embodiments, the acid is tartaric acid.

[0094] In some embodiments, the reaction solution is washed with an aqueous basic solution. For instance, in some embodiments, the reaction solution is washed with about 1% to about 3% aqueous base. In some embodiments, the base is sodium bicarbonate. In some embodiments, the base is potassium phosphate dibasic. In some embodiments, the base is sodium phosphate dibasic. In some embodiments, the aqueous basic solution is 2% aqueous sodium bicarbonate.

[0095] In some embodiments, the crude product solution of step (a) of step S-1 (i.e., the washed reaction solution) is taken into step (b) of step S-1 without further treatment or purification. For instance, in some embodiments, the crude product solution of step (a) is added directly to an inert, fresh reaction vessel containing reagents required for step (b) of step S-1 (e.g., tert-butyl carbamate, base, catalyst, and ligand). Accordingly, in some embodiments, step (b) of step S-1 is conducted in the same solvent as step (a). In some embodiments, step (b) of step S-1 is conducted in a solvent comprising an aromatic solvent. For instance, in some embodiments, step (b) of step S-1 is conducted in a solvent comprising benzene, toluene, or xylene. In certain embodiments, step (b) of step S-1 is conducted in a solvent comprising toluene.

[0096] In some embodiments, the base of step (b) of step S-1 is an inorganic base. In some embodiments, the base is a carbonate base. For instance, in some embodiments, the base is sodium carbonate, potassium carbonate, or cesium carbonate. In certain embodiments, the base is cesium carbonate.

[0097] In some embodiments, the catalyst of step (b) of step S-1 is a transition metal catalyst. In some embodiments, the catalyst is a palladium catalyst. In certain embodiments, the catalyst is palladium acetate. In some embodiments, the ligand is an organophosphorus ligand. In some embodiments, the ligand is a bidentate organophosphorus ligand. In certain embodiments, the ligand is Xantphos (i.e., 4,5-bis(diphenylphosphino)-9,9-dimethylxanthene). Other palladium catalysts and ligands are known in the art and are contemplated herein. See, for example, 1) Surry, David S.; Buchwald, Stephen L. Chem. Sci. 2011, 2, 27-50; and 2) Maiti, Debabrata, et al., Chem. Sci. 2011, 2, 57-68) each of which are incorporated herein by reference.

[0098] In some embodiments, step (b) of step S-1 comprises heating the reaction mixture to between about 80 °C and about 105 °C. In some embodiments, the reaction mixture is heated to about 80 °C, about 85 °C, about 90 °C, about 95 °C, about 100 °C, or about 105 °C. In some embodiments, the reaction mixture is heated for between about 10 hours and about 24 hours. In some embodiments, the reaction is heated for about 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, or 24 hours. In certain embodiments, step (b) of step S-1 comprises heating the reaction mixture to about 95 °C for about 16 hours. In some embodiments, upon reaction completion, the reaction mixture is cooled to about 25 °C and an amount of diatomaceous earth is charged. The reaction mixture is then agitated, filtered, and vacuum distilled at an elevated temperature (e.g., about 80 °C or lower) to reduce solvent volume.

[0099] In some embodiments, the reaction solution is then exposed a catalyst scavenger, for instance a palladium catalyst scavenger, in order to remove residual catalyst from the reaction mixture. In certain embodiments, a catalyst scavenger comprises activated carbon in the presence of trithiocyanuric acid. Other such catalyst scavengers are known in the art. See, for example, Wang, Lijun et al. Org. Process Res. Dev. 2011, 15, 1371-1376, incorporated herein by reference. In some embodiments, an alkane solvent (e.g., n-heptane) is added to the mixture and the mixture is then agitated at about 25 °C for at least about four hours, about six hours, or about eight hours prior to being filtered.

[00100] In some embodiments, the resulting filter cake is then washed at least once, twice, or three times with a solution comprising one or more organic solvents. For instance, in some embodiments, such a solution comprises an aromatic solvent (e.g., toluene). In some embodiments, such a solution comprises an alkane solvent (e.g., n-heptane). In certain embodiments, such a solution comprises an aromatic solvent (e.g., toluene) and an alkane solvent (e.g., n-heptane). In some such embodiments, such a solution comprises an excess of an alkane solvent relative to aromatic solvent (e.g., about 5/1 v/v n-heptane/toluene). In some embodiments, the filter cake is washed at least twice with such a solution prior to charging the filtrate with fresh activated carbon. In some embodiments, the filtrate containing fresh activated carbon is agitated for at least about 1, about 2, about 3, or about 4 hours at about 25 °C, again filtered, and again washed at least once with a solution as described above (e.g., a solution comprising about 5/1 v/v n-heptane/toluene).

[00101] In some embodiments, the resulting filtrate is vacuumed distilled at a temperature of about 65 °C or lower in order to reduce solvent volume. In certain embodiments, upon reduction of solvent volume to a desired amount, a second solvent is added to the filtrate to effect a solvent exchange. In certain embodiments, such a solvent exchange employs an alkane solvent (e.g., n- heptane) as a second solvent. In some embodiments, once the solvent exchange step is complete, the solution is cooled to about 10 °C, seeded intermittently with a crystalline form of a compound of formula E (e.g., compound 7, depicted below), and agitated at about 10 °C or higher for an amount of time to allow crystallization to occur. In some embodiments, the resulting solids are then filtered and washed at least once with an alkane solvent (e.g., n- heptane). In some embodiments, the washed solids are then dried under reduced pressure at a temperature of between about 20 °C and about 60 °C. In some embodiments, the washed solids are dried at a temperature of between about 25 °C and about 55 °C. In some embodiments, the washed solids are dried at a temperature of between about 30 °C and about 50 °C. In some embodiments, the washed solids are dried at a temperature of between about 35 °C and about 45 °C. In some embodiments, the washed solids are dried at a temperature of about 40 °C.

[00102] In some embodiments, a compound of formula E is compound 7:

[00103] It is contemplated that compound 7 can exist in a variety of physical forms. For example, compound 7 can be in solution, suspension, or in solid form. In certain embodiments, compound 7 is in solid form. When compound 7 is in solid form, said compound may be amorphous, crystalline, or a mixture thereof. Exemplary solid forms are described in more detail below.

[00104] In some embodiments, the present invention provides a form of compound 7 substantially free of impurities. As used herein, the term "substantially free of impurities" means that the compound contains no significant amount of extraneous matter. Such extraneous matter may include different forms of compound 7, residual solvents, or any other impurities that may result from the preparation of, and/or isolation of, compound 7.

[00105] According to one embodiment, a form of compound 7 is present in an amount of at least about 97, 97.5, 98.0, 98.5, 99, 99.5, 99.8 weight percent where the percentages are based on the total weight of the composition. According to another embodiment, a form of compound 7 contains no more than about 3.0 area percent HPLC of total organic impurities and, in certain embodiments, no more than about 1.5 area percent HPLC total organic impurities relative to the total area of the HPLC chromatogram. In other embodiments, a form of compound 7 contains no more than about 1.0% area percent HPLC of any single impurity; no more than about 0.6 area percent HPLC of any single impurity, and, in certain embodiments, no more than about 0.5 area percent HPLC of any single impurity, relative to the total area of the HPLC chromatogram.

[00106] It has been found that compound 7 can exist in a variety of solid forms. Exemplary such forms include polymorphs such as the polymorph described herein.

[00107] As used herein, the term "polymorph" refers to the different crystal structures into which a compound, or a salt or solvate thereof, can crystallize.

[00108] In certain embodiments, compound 7 is a crystalline solid. In certain embodiments, compound 7 is a crystalline solid substantially free of amorphous compound 7. As used herein, the term "substantially free of amorphous compound 7" means that the compound contains no significant amount of amorphous compound 7. In certain embodiments, at least about 95% by weight of crystalline compound 7 is present. In still other embodiments of the invention, at least about 99% by weight of crystalline compound 7 is present.

[00109] It has been found that compound 7 can exist in at least one distinct polymorphic form. In certain embodiments, the present invention provides a polymorphic form of compound 7 referred to herein as Form A of compound 7.

Form A of Compound 7

[00110] In some embodiments, Form A of compound 7 has at least 1, 2, 3, 4 or 5 spectral peak(s) selected from the peaks listed in Table 1 below.

Table 1 - XRPD Peak Positions for Form A of Compound 7

¹ In this and al subsequent tables,

the position 2 Θ is within ± 0.2.

[00111] In some embodiments, Form A of compound 7 is characterized in that it has one or more peaks in its X-ray powder diffraction pattern selected from those at about 16.7, 19.6, and 19.9. In some embodiments, Form A of compound 7 is characterized in that it has two or more peaks in its X-ray powder diffraction pattern selected from those at about 16.7, 19.6, and 19.9. In some embodiments, Form A of compound 7 is characterized in that it has all three peaks in its X-ray powder diffraction pattern selected from those at about 16.7, 19.6, and 19.9. In some embodiments, Form A of compound 7 is characterized in that it has one or more peaks in its X- ray powder diffraction pattern selected from those at about 16.7 and 19.6. In some embodiments, Form A of compound 7 is characterized in that it has at least three peaks in its X- ray powder diffraction pattern selected from those at about 13.4, 14.4, 16.7, 19.6, and 19.9. [00112] As used herein, the term "about", when used in reference to a degree 2-theta value refers to the stated value ± 0.2 degree 2-theta.

[00113] In certain embodiments, Form A of compound 7 is characterized by having an X-ray powder diffraction pattern substantially similar to the XRPD provided in Figure 1.

[00114] In certain embodiments, Form A of compound 7 is characterized by having a DSC thermogram substantially similar to that of Figure 2.

[00115] Methods for preparing Form A of compound 7 are described infra.

[00116] At step S-2 of Scheme I, a compound of formula D is coupled to a compound of formula E via nucleophilic displacement of LG¹ by the amine group of formula E to provide a compound of formula C. Suitable conditions for the nucleophilic displacement are well known in the art, including but not limited to those described in March's Advanced Organic Chemistry: Reactions, Mechanisms, and Structure, M. B. Smith and J. March, 5th Edition, John Wiley & Sons, 2001; and Comprehensive Organic Transformaions, R. C. Larock, 2nd Edition, John Wiley & Sons, 1999.

[00117] Each of LG¹ and LG² is independently a suitable leaving group that is subject to nucleophilic displacement. As defined herein, a suitable "leaving group" that is "subject to nucleophilic displacement" is a chemical group that is readily displaced by a desired incoming nucleophilic chemical entity. Suitable leaving groups are well known in the art, e.g., see generally, March's Advanced Organic Chemistry: Reactions, Mechanisms, and Structure, M. B. Smith and J. March, 5^th Edition, John Wiley & Sons, 2001. Such leaving groups include, but are not limited to, halogen, alkoxy, ester, carbonate, sulphonyloxy, optionally substituted alkylsulphonyloxy, optionally substituted alkenylsulfonyloxy, optionally substituted arylsulfonyloxy, phosphonate, sulfoxide, sulphone, and diazonium moieties. For the above mentioned "optionally substituted" moieties, the moieties may be optionally substituted with Ci_₄ aliphatic, fluoro-substituted Ci_₄ aliphatic, halogen, or nitro. Examples of suitable leaving groups include chloro, iodo, bromo, fluoro, sulfoxide, sulphone, methanesulfonyloxy (mesyloxy), tosyloxy, triflyloxy, benzenesulfonyloxy, nitro-phenylsulfonyloxy (nosyloxy), and bromo-phenylsulfonyloxy (brosyloxy).

[00118] In some embodiments, a leaving group is chloro.

[00119] In some embodiments, LG¹ is halogen. In some embodiments, LG¹ is -CI. In some embodiments, LG¹ is -Br. In some embodiments, LG¹ is -I. [00120] In some embodiments, LG² is halogen. In some embodiments, LG² is -CI. In some embodiments, LG² is -Br. In some embodiments, LG² is -I.

[00121] In some embodiments, each of LG¹ and LG² is independently halogen. In some embodiments, each of LG¹ and LG² is -CI.

[00122] In some embodiments, a provided compound of formula D is compound 2:

[00123] In some embodiments, step S-2 is conducted in the presence of a base. A suitable base for a provided step can be either organic or inorganic.

[00124] In some embodiments, step S-2 is conducted in an inorganic base.

[00125] In some embodiments, a base is an alkoxide. For instance, in some embodiments, a base is LiOR, NaOR, or KOR, wherein R is optionally substituted Ci_-6 aliphatic or aryl.

[00126] In some embodiments, a base is an alkoxide such as LiOR, NaOR, or KOR, wherein

R is optionally substituted Ci_-6 aliphatic. In some embodiments, a base is an alkoxide such as

LiOR, NaOR, or KOR, wherein R is a butyl group.

[00127] In certain embodiments, the base is LiOtBU, NaOtBU , or KOtBU.

[00128] In certain embodiments, the base is KOtBU.

[00129] In some embodiments, a base is an amide base. For instance, in some embodiments, a base is lithium hexamethyldisilazide, sodium hexamethyldisilazide, or potassium hexam ethyl di sil azi de .

[00130] In some embodiments, step S-2 is conducted in a solvent comprising a polar aprotic solvent. In some embodiments, step S-2 is conducted in a solvent comprising an ether. In some embodiments, an ether is TUF. Numerous other aprotic solvents are known in the art and are contemplated herein.

[00131] In some embodiments, step S-2 is conducted at reduced temperatures. For instance, in some embodiments, step S-2 is conducted at temperatures below about 0 °C. In some embodiments, step S-2 is conducted at temperatures below about -5 °C. In some embodiments, step S-2 is conducted at temperatures below about -10 °C. In some embodiments, step S-2 is conducted at temperatures below about -15 °C. In some embodiments, step S-2 is conducted at temperatures below about -20 °C. In some embodiments, step S-2 is conducted at temperatures below about -25 °C. In some embodiments, step S-2 is conducted at temperatures between about -5 °C and about -25 °C. In some embodiments, step S-2 is conducted at temperatures between about -5 °C and about -20 °C. In some embodiments, step S-2 is conducted at temperatures between about -10 °C and about -25 °C. In some embodiments, step S-2 is conducted at temperatures between about -5 °C and about -15 °C. In some embodiments, step S-2 is conducted at temperatures between about -10 °C and about -20 °C. In some embodiments, step S-2 is conducted at a temperature of about -15 °C.

[00132] In some embodiments, the base of step S-2 (e.g., KOt-Bu) is added to the reaction mixture over a period of time. In some embodiments, addition occurs while the reaction mixture is held at a reduced temperature. For instance, in some embodiments, addition to the reaction mixture occurs at a reduced temperature for about 10, 20, 30, 40, 50, 60, 70, 80, 90, 100, 110 or 120 minutes. In some embodiments, addition to the reaction mixture occurs at a reduced temperature for about 60 to about 120 minutes. In some embodiments, addition to the reaction mixture occurs at a reduced temperature for about 90 minutes.

[00133] In some embodiments, an additional amount of base is added in portions to the reaction mixture until a desired level of conversion is achieved. In some embodiments, once a desired level of conversion is achieved, the reaction is allowed to warm (e.g., to about 0 °C) and is quenched (e.g., with water). After quenching, an organic solvent (e.g., heptane) is added, followed by extraction of the organic layer. In some embodiments, the organic layer is then washed with water 1, 2, 3, 4, or 5 times.

[00134] In some embodiments, the organic layer is treated (e.g., stirred) with a filter media (e.g., activated carbon) for an amount of time. In some embodiments, treatment with a filter media occurs for about 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, or 24 hours. In certain embodiments, treatment occurs for between about 12 and about 20 hours. In certain embodiments, treatment occurs for about 16 hours. In some embodiments, following such a treatment, the organic layer is filtered (e.g., through a pad of diatomaceous earth). In some such embodiments, the filter media is washed with several portions of an organic solvent (e.g., THF), the filtrates are combined, and an amount of solvent is removed (e.g., via distillation). [00135] In some embodiments, after initial removal of an amount of solvent, continuous vacuum distillation is performed using an organic solvent such as an alkane (e.g., a pentane, a hexane, or a heptane). In certain embodiments, continuous vacuum distillation is performed until the solution comprises a desired solvent volume or composition. For instance, in some embodiments, a first distillation is performed to remove solvents used during work-up and/or treatment with a filter media (e.g., activated carbon), followed by a second, continuous distillation (with, e.g., n-heptane), wherein the second, continuous distillation proceeds until a particular solvent composition or volume is achieved.

[00136] In some embodiments, the above-described distillations are performed prior to crystallization. In some embodiments, the product solution comprising a desired composition of solvent is set to a particular temperature (e.g., between about 50 °C to about 60 °C) and seeded with seed crystals. For instance, in some embodiments, seeding occurs with a particular polymorph of a compound of formula C. Exemplary such polymorphs are contemplated further below.

[00137] In some embodiments, crystallization further comprises one or more steps of agitating for an amount of time. For instance, in some embodiments, agitation lasts for about 5, 10, 15, 20, 25, 30, 35, 40, 45, 50, 55, 60, 65, 70, 75, 80, 85, 90, 95, 100, 105, 110, 115, or 120 minutes. In certain embodiments, agitation lasts for between about 45 minutes to about 65 minutes. In certain embodiments, agitation lasts for about 60 minutes.

[00138] In some embodiments, crystallization comprises a step of cooling the agitated solution over a period of time. For instance, in some embodiments, the solution is cooled to between about 0 °C and about 20 °C. In some embodiments, the solution is cooled to between about 5 °C and about 15 °C. In some embodiments, the solution is cooled to about 10 °C. In some embodiments, cooling takes place over an amount of time, for instance, over about 1, 2, 3, 4, 5, or 6 hours. In certain embodiments, a solution is cooled for about 2 hours. In certain embodiments, a solution is cooled for about 3 hours. In certain embodiments, a solution is cooled for about 4 hours.

[00139] In some embodiments, crystallization comprises a step of agitating the cooled solution. In some embodiments, the cooled solution is agitated for about 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, or 24 hours. In certain embodiments, the cooled solution is agitated for between about 2 hours and about 6 hours. In certain embodiments, the cooled solution is agitated for about 4 hours.

[00140] In some embodiments, upon completion of crystallization, the resulting product (i.e., a compound of formula C) is filtered, washed with an amount of solvent (e.g., an alkane such as n-heptane), and dried.

[00141] In some embodiments, a provided compound of formula C is compound 8:

[00142] It is contemplated that compound 8 can exist in a variety of physical forms. For example, compound 8 can be in solution, suspension, or in solid form. In certain embodiments, compound 8 is in solid form. When compound 8 is in solid form, said compound may be amorphous, crystalline, or a mixture thereof. Exemplary solid forms are described in more detail below.

[00143] In some embodiments, the present invention provides a form of compound 8 substantially free of impurities. As used herein, the term "substantially free of impurities" means that the compound contains no significant amount of extraneous matter. Such extraneous matter may include different forms of compound 8, residual solvents, or any other impurities that may result from the preparation of, and/or isolation of, compound 8.

[00144] According to one embodiment, a form of compound 8 is present in an amount of at least about 97, 97.5, 98.0, 98.5, 99, 99.5, 99.8 weight percent where the percentages are based on the total weight of the composition. According to another embodiment, a form of compound 8 contains no more than about 3.0 area percent HPLC of total organic impurities and, in certain embodiments, no more than about 1.5 area percent HPLC total organic impurities relative to the total area of the HPLC chromatogram. In other embodiments, a form of compound 8 contains no more than about 1.0% area percent HPLC of any single impurity; no more than about 0.6 area percent HPLC of any single impurity, and, in certain embodiments, no more than about 0.5 area percent HPLC of any single impurity, relative to the total area of the HPLC chromatogram. [00145] It has been found that compound 8 can exist in a variety of solid forms. Exemplary such forms include polymorphs such as the polymorph described herein.

[00146] In certain embodiments, compound 8 is a crystalline solid. In certain embodiments, compound 8 is a crystalline solid substantially free of amorphous compound 8. As used herein, the term "substantially free of amorphous compound 8" means that the compound contains no significant amount of amorphous compound 8. In certain embodiments, at least about 95% by weight of crystalline compound 8 is present. In still other embodiments of the invention, at least about 99% by weight of crystalline compound 8 is present.

[00147] It has been found that compound 8 can exist in at least one distinct polymorphic form. In certain embodiments, the present invention provides a polymorphic form of compound 8 referred to herein as Form A of compound 8.

Form A of Compound 8

[00148] In some embodiments, Form A of compound 8 has at least 1, 2, 3, 4 or 5 spectral peak(s) selected from the peaks listed in Table 2 below.

Table 2 - XRPD Peak Positions for Form A of Compound 8

subsequent tables,

the position 2 Θ is within ± 0.2.

[00149] In some embodiments, Form A of compound 8 is characterized in that it has one or more peaks in its X-ray powder diffraction pattern selected from those at about 9.3, 19.6, and 20.0. In some embodiments, Form A of compound 8 is characterized in that it has two or more peaks in its X-ray powder diffraction pattern selected from those at about 9.3, 19.6, and 20.0. In some embodiments, Form A of compound 8 is characterized in that it has all three peaks in its X- ray powder diffraction pattern selected from those at about 9.3, 19.6, and 20.0. In some embodiments, Form A of compound 8 is characterized in that it has one or more peaks in its X- ray powder diffraction pattern selected from those at about 9.3 and 20.0. In some embodiments, Form A of compound 8 is characterized in that it has at least three peaks in its X-ray powder diffraction pattern selected from those at about 9.3, 19.6, 20.0, 23.3, and 24.5.

[00150] As used herein, the term "about", when used in reference to a degree 2-theta value refers to the stated value ± 0.2 degree 2-theta.

[00151] In certain embodiments, Form A of compound 8 is characterized by having an X-ray powder diffraction pattern substantially similar to the XRPD provided in Figure 3.

[00152] In certain embodiments, Form A of compound 8 is characterized by having a DSC thermogram substantially similar to that of Figure 4.

[00153] Methods for preparing Form A of compound 8 are described infra.

[00154] At step S-3 of Scheme I, a compound of formula C is coupled to compound B via nucleophilic displacement of LG² by the amine group of compound B. In some embodiments, compound B is provided in the form of a salt. Accordingly, compound B as depicted in Scheme I will be understood to contemplate the use of either the free base form of compound B or the salt form of compound B. In certain embodiments, compound B is provided as the HC1 salt:

H

B

[00155] Exemplary methods of making compound B, or a salt thereof, are described in further detail infra.

[00156] Suitable conditions for the nucleophilic displacement are well known in the art, including but not limited to those described in March's Advanced Organic Chemistry: Reactions, Mechanisms, and Structure, M. B. Smith and J. March, 5^th Edition, John Wiley & Sons, 2001; and Comprehensive Organic Transformaions, R. C. Larock, 2^nd Edition, John Wiley & Sons, 1999. For instance, in some embodiments, step S-3 occurs via metal-catalyzed cross-coupling, such as a Pd-catalyzed cross-coupling. In some embodiments, the coupling is not metal- catalyzed. [00157] In some embodiments, step S-3 is conducted in the presence of a base. In some embodiments, a base is an organic base, such as a tertiary amine. In some embodiments, a tertiary amine is triethylamine (TEA). In some embodiments, a tertiary amine is diisopropylethylamine (DIPEA). In some embodiments, an organic base is a heteroaromatic compound comprising an aromatic and basic nitrogen atom. In some embodiments, a base is pyridine. In some embodiments, a base is 2,6-lutidine. In some embodiments, a base is DMAP.

[00158] In some embodiments, step S-3 is conducted in a polar aprotic solvent. In some embodiments, a solvent comprises an amine. In some embodiments, step S-3 is conducted in an amine solvent such as, e.g., dimethylformamide (DMF), dimethylacetamide (DMAc) or N- methyl-2-pyrrolidinone (NMP). In certain embodiments, an amine solvent is N-methyl-2- pyrrolidinone (NMP).

[00159] In some embodiments, step S-3 is initiated at a temperature between about 10 °C and about 40 °C. In some embodiments, step S-3 is initiated at a temperature between about 20 °C and about 30 °C. In certain embodiments, step S-3 comprises one or more steps of heating. For instance, in some embodiments, step S-3 comprises one or more steps of heating to between about 60 °C and about 80 °C. In certain embodiments, step S-3 comprises a first step of heating to between about 65 °C and about 70 °C for about 10, 15, 20, 25, or 30 hours, followed by a second step of heating to between about 67 °C and about 73 °C for about 1, 2, 3, 4, 5, 6, 7, or 8 hours. In some embodiments, a step of heating is continued until no more than about 1%, 2%, 3%, 4%, or 5% of starting material (i.e., a compound of formula C) remains.

[00160] In some embodiments, once a desired level of conversion is achieved, the reaction is allowed to cool (e.g., to between about 25 °C and about 35 °C) prior to quenching. In some embodiments, the reaction is diluted with an organic solvent (e.g., isopropyl acetate) and quenched with aqueous acid (e.g., aqueous citric acid). In some embodiments, the organic layer is washed repeatedly with aqueous acid (e.g., aqueous citric acid). In some embodiments, the organic layer is washed with aqueous acid 1, 2, 3, 4, or 5 times. In some embodiments, the organic layer is washed repeatedly with aqueous base (e.g., a sodium bicarbonate solution). In some embodiments, the organic layer is washed with aqueous base 1, 2, 3, 4, or 5 times. In some embodiments, the organic layer is washed with water. In some embodiments, the organic layer is washed with water 1, 2, 3, 4, or 5 times. [00161] In some embodiments, the organic layer is treated (e.g., stirred) with a filter media (e.g., activated carbon) for an amount of time. In some embodiments, an amount of solvent is removed from the organic layer (e.g., via distillation) prior to treatment with a filter media (e.g., activated carbon). In some embodiments, an amount solvent (e.g., isopropyl acetate) is added to the organic layer prior to treatment with a filter media. In some embodiments, treatment with a filter media occurs for about 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, or 24 hours. In certain embodiments, treatment occurs for between about 2 and about 6 hours. In certain embodiments, treatment occurs for about 4 hours. In some embodiments, following treatment with a filter media, the organic layer is filtered (e.g., through a pad of diatomaceous earth). In some such embodiments, the filter media is washed with several portions of an organic solvent (e.g., isopropyl acetate), the filtrates are combined, and an amount of solvent is removed (e.g., via distillation).

[00162] In some embodiments, after removal of an amount of solvent (e.g., via distillation), continuous vacuum distillation is performed using an organic solvent (e.g., an alkane). For instance, in some embodiments, an organic solvent is an alkane such as a hexane or a heptane. In certain embodiments, continuous vacuum distillation is performed until a desired solvent composition or volume is achieved. For instance, in some embodiments, a first distillation is performed to remove solvents (e.g., isopropyl acetate) used during work-up and/or treatment with a filter media, followed by a second, continuous distillation with an organic solvent such as an alkane (e.g., n-heptane), wherein the second, continuous distillation proceeds until a desired solvent composition or volume is achieved.

[00163] In some embodiments, the above-described distillations are performed prior to crystallization. In some embodiments, the solution is set to a particular temperature (e.g., between about 45 °C and about 55 °C) and seeded with seed crystals of a compound of formula A. For instance, in some embodiments, seeding occurs with a particular polymorph of a compound of formula A. Exemplary such polymorphs are contemplated further below.

[00164] In some embodiments, crystallization comprises one or more steps of agitating for an amount of time. For instance, in some embodiments, agitation lasts for about 1, 2, 3, 4, 5, 6, 7, 8, 9, or 10 hours. In some embodiments, crystallization further comprises a step of cooling (e.g., to about 25 °C). [00165] In some embodiments, crystallization comprises a step of aging at a particular temperature for a particular amount of time. For instance, in certain embodiments, crystallization comprises aging at about 25 °C for about 1, 2, 3, 4, 5, or 6 hours.

[00166] In some embodiments, upon completion of crystallization, the resulting product (i.e., a compound of formula A) is filtered, washed with an amount of solvent (e.g., a 1 :4 isopropyl acetate: heptane solution), and dried.

[00167] In some embodiments, a provided com ound of formula A is compound 9:

9

[00168] It is contemplated that compound 9 can exist in a variety of physical forms. For example, compound 9 can be in solution, suspension, or in solid form. In certain embodiments, compound 9 is in solid form. When compound 9 is in solid form, said compound may be amorphous, crystalline, or a mixture thereof. Exemplary solid forms are described in more detail below.

[00169] In some embodiments, the present invention provides a form of compound 9 substantially free of impurities. As used herein, the term "substantially free of impurities" means that the compound contains no significant amount of extraneous matter. Such extraneous matter may include different forms of compound 9, residual solvents, or any other impurities that may result from the preparation of, and/or isolation of, compound 9.

[00170] According to one embodiment, a form of compound 9 is present in an amount of at least about 97, 97.5, 98.0, 98.5, 99, 99.5, 99.8 weight percent where the percentages are based on the total weight of the composition. According to another embodiment, a form of compound 9 contains no more than about 3.0 area percent UPLC of total organic impurities and, in certain embodiments, no more than about 1.5 area percent UPLC total organic impurities relative to the total area of the UPLC chromatogram. In other embodiments, a form of compound 9 contains no more than about 1.0% area percent HPLC of any single impurity; no more than about 0.6 area percent HPLC of any single impurity, and, in certain embodiments, no more than about 0.5 area percent HPLC of any single impurity, relative to the total area of the HPLC chromatogram.

[00171] It has been found that compound 9 can exist in a variety of solid forms. Exemplary such forms include polymorphs such as those described herein.

[00172] In certain embodiments, compound 9 is a crystalline solid. In other embodiments, compound 9 is a crystalline solid substantially free of amorphous compound 9. As used herein, the term "substantially free of amorphous compound 9" means that the compound contains no significant amount of amorphous compound 9. In certain embodiments, at least about 95% by weight of crystalline compound 9 is present. In still other embodiments of the invention, at least about 99% by weight of crystalline compound 9 is present.

[00173] It has been found that compound 9 can exist in at least two distinct polymorphic forms. In certain embodiments, the present invention provides a polymorphic form of compound 9 referred to herein as Form A of compound 9. In certain embodiments, the present invention provides a polymorphic form of compound 9 referred to herein as Form B of compound 9.

Form A of Compound 9

[00174] In some embodiments, Form A of compound 9 has at least 1, 2, 3, 4 or 5 spectral peak(s) selected from the peaks listed in Table 3 below.

Table 3 - XRPD Peak Positions for Form A of Compound 9

¹ In this and al subsequent tables,

the position 2 Θ is within ± 0.2.

[00175] In some embodiments, Form A of compound 9 is characterized in that it has one or more peaks in its X-ray powder diffraction pattern selected from those at about 5.8, 8.4 and 11.5. In some embodiments, Form A of compound 9 is characterized in that it has two or more peaks in its X-ray powder diffraction pattern selected from those at about 5.8, 8.4 and 11.5. In some embodiments, Form A of compound 9 is characterized in that it has all three peaks in its X-ray powder diffraction pattern selected from those at about 5.8, 8.4 and 11.5. In some embodiments, Form A of compound 9 is characterized in that it has one or more peaks in its X-ray powder diffraction pattern selected from those at about 5.8 and 8.4. In some embodiments, Form A of compound 9 is characterized in that it has at least three peaks in its X-ray powder diffraction pattern selected from those at about 5.8, 8.4, 10.6, 11.5, and 18.8.

[00176] As used herein, the term "about", when used in reference to a degree 2-theta value refers to the stated value ± 0.2 degree 2-theta.

[00177] In certain embodiments, Form A of compound 9 is characterized by having an X-ray powder diffraction pattern substantially similar to the XRPD provided in Figure 5.

[00178] In certain embodiments, Form A of compound 9 is characterized by having a DSC thermogram substantially similar to that of Figure 6.

[00179] Methods for preparing Form A of compound 9 are described infra.

Form B of Compound 9

[00180] In some embodiments, Form B of compound 9 has at least 1, 2, 3, 4 or 5 spectral peak(s) selected from the peaks listed in Table 4 below.

Table 4 - XRPD Peak Positions for Form B of Compound 9

¹ In this and al subsequent tables,

the position 2 Θ is within ± 0.2.

[00181] In some embodiments, Form B of compound 9 is characterized in that it has one or more peaks in its X-ray powder diffraction pattern selected from those at about 7.0, 14.1, and 21.2. In some embodiments, Form B of compound 9 is characterized in that it has two or more peaks in its X-ray powder diffraction pattern selected from those at about 7.0, 14.1, and 21.2. In some embodiments, Form B of compound 9 is characterized in that it has all three peaks in its X- ray powder diffraction pattern selected from those at about 7.0, 14.1, and 21.2. In some embodiments, Form B of compound 9 is characterized in that it has one or more peaks in its X- ray powder diffraction pattern selected from those at about 7.0 and 21.2. In some embodiments, Form B of compound 9 is characterized in that it has at least three peaks in its X-ray powder diffraction pattern selected from those at about 7.0, 9.9, 14.1, 16.6, and 21.2.

[00182] As used herein, the term "about", when used in reference to a degree 2-theta value refers to the stated value ± 0.2 degree 2-theta.

[00183] In certain embodiments, Form B of compound 9 is characterized by having an X-ray powder diffraction pattern substantially similar to the XRPD provided in Figure 7.

[00184] In certain embodiments, Form B of compound 9 is characterized by having a DSC thermogram substantially similar to that of Figure 8.

[00185] Methods for preparing Form B of compound 9 are described infra.

[00186] At step S-4 of Scheme I, a compound of formula A is deprotected to provide free amine Compound I. In certain embodiments, the PG¹ group of formula A is removed by acid. In some embodiments, the acid is a Lewis acid. In some embodiments, the acid is a Bronsted acid. For example, in some embodiments, the PG¹ group of formula A is removed with sulfuric acid. In certain embodiments, the PG¹ group of formula A is removed with a solution of sulfuric acid in a medium such as an alcohol (e.g., methanol). In some embodiments, the PG¹ group of formula A is removed with a sulfonic acid, for instance, ^-toluenesulfonic acid (PTSA) or methanesulfonic acid. In some embodiments, the PG¹ group of formula A is removed with phosphoric acid. One of ordinary skill in the art would recognize that a wide variety of acids are useful for removing amino protecting groups that are acid-labile.

[00187] In some embodiments, the solution of acid of step S-4 (e.g., sulfuric acid in methanol) is added to the reaction mixture over a period of time. In some embodiments, addition occurs while the reaction mixture is held at a temperature of no more than about 30 °C.

[00188] In some embodiments, after the addition of acid, a reaction mixture is heated to about 35 °C to about 45 °C and agitated for about 1, 2, 3, 4, 5, 6, 7 or 8 hours. In some embodiments, a step of heating is continued until less than about 0.5%, 1%, 2%, 3%, 4%, or 5% of starting material (i.e., a compound of formula A) remains. [00189] In some embodiments, the step of deprotecting is followed by an additional step of treating the deprotected material with an amount of base. In certain embodiments, the deprotected material is treated with an amine base (e.g., triethylamine or diisopropylethylamine). In certain embodiments, an amine base (e.g., triethylamine) is first dissolved in a solvent such as an alcohol (e.g., methanol). In some embodiments, the solution of amine base of step S-4 (e.g., triethylamine in methanol) is added to the reaction mixture over a period of time. In some embodiments, addition occurs while the reaction mixture is held at a temperature of no more than about 20 °C to about 30 °C. In some embodiments, the reaction is stirred until Compound I precipitates out of solution. In certain embodiments, the reaction is stirred for about 5, 10, 15, 20, 25, 30, 35, 40, 45, 50, 55, 60, 65, 70, 75, 80, 85, or 90 minutes. In certain embodiments, the reaction is stirred for about 45 minutes to about 75 minutes. In certain embodiments, the reaction is stirred for about 60 minutes.

[00190] In some embodiments, the reaction is agitated for about 1, 2, 3, 4, 5, 6, 7, or 8 hours. In certain embodiments, the reaction is agitated for about 3 hours to about 5 hours. In some embodiments, the reaction is agitated for about 4 hours.

[00191] In some embodiments, the precipitate is filtered, washed with an organic solvent (e.g., an alcoholic solvent such as methanol), and dried to afford Compound I:

H

Compound I.

[00192] One of ordinary skill in the art will appreciate that Compound I, as prepared by methods of the present invention, may be treated with a suitable acid to form a salt thereof. For instance, at step S-5 of Scheme I, Compound I is treated with a suitable acid to afford the corresponding salt of Compound I. Exemplary such suitable acids and salts are as described above and herein.

[00193] In some embodiments, Compound I, or a salt thereof, may be treated with a suitable Bransted acid (herein denoted as ΉΧ"), as depicted in step S-5, to form a pharmaceutically acceptable salt thereof (represented by Compound ΓΗΧ). Exemplary acids include, but are not limited to, organic and inorganic acids such as acetic, lactic, citric, cinnamic, tartaric, succinic, fumaric, maleic, malonic, mandelic, malic, oxalic, propionic, hydrochloric, hydrobromic, phosphoric, nitric, sulfuric, glycolic, pyruvic, methanesulfonic, ethanesulfonic, toluenesulfonic, benzenesulfonic, salicylic, benzoic, or similarly known acceptable acids. In certain embodiments, compound I is treated with phosphoric acid to form a compound of formula ΓΗΧ wherein X represents a phosphate conjugate base.

[00194] In some embodiments, salt formation comprises dissolving Compound I in an amount of suitable solvent (e.g., THF and water), performing a polish filtration, charging the reaction with an amount of an acid (e.g., H₃PO₄), seeding with a selected form of Compound I (e.g., polymorph Form A of a phosphate salt form of Compound I), performing a solvent exchange (e.g., from THF and water to EtOH or EtOAc), filtering the reaction, and drying the reaction to afford an particular form of a salt of Compound I (e.g., polymorph Form A of a phosphate salt form of Compound I).

[00195] In some embodiments, salt formation comprises dissolving Compound I in an amount of suitable solvent (e.g., THF and water), performing a polish filtration, performing a solvent exchange (e.g., from THF and water to EtOH), crystallizing Compound I, charging the reaction with an amount of an acid (e.g., H₃PO₄ in EtOH), seeding with a selected form of Compound I (e.g., polymorph Form A of a phosphate salt form of Compound I), filtering the reaction, and drying the reaction to afford an particular form of a salt of Compound I (e.g., polymorph Form A of a phosphate salt form of Compound I).

[00196] In some embodiments, salt formation comprises dissolving Compound I in an amount of suitable solvent (e.g., THF and water), performing a polish filtration, performing a solvent exchange (e.g., from THF and water to EtOAc, wherein residual THF is no more than 2.0 wt%), seeding with a selected form of Compound I (e.g., polymorph Form A of a phosphate salt form of Compound I), charging the reaction with an amount of an acid (e.g., H₃PO₄ in EtOH, wherein the final ratio of EtOAc:EtOH is 13:5), filtering the reaction, and drying the reaction to afford an particular form of a salt of Compound I (e.g., polymorph Form A of a phosphate salt form of Compound I).

[00197] In some embodiments, salt formation comprises a first step of treating Compound I, for instance by dissolving Compound I in a suitable solvent and atmospherically distilling the solution until a particular solvent volume or composition is achieved. In some embodiments, a solvent is an ether (e.g., THF). In some embodiments, a solvent is a mixture of an aqueous and organic solvent. For instance, in certain embodiments, a solvent is a mixture of an ether and water (e.g., 95:5 THF : water v/v).

[00198] In some embodiments, after removal of an amount of solvent (e.g., via distillation), a second, continuous vacuum distillation is performed using an additional solvent. In some embodiments, a solvent comprises a polar aprotic solvent such as an alkyl acetate. In some embodiments, a solvent comprises ethyl acetate. In some embodiments, a solvent is ethyl acetate. In some embodiments, a solvent comprises isopropyl acetate. In some embodiments, a solvent is isopropyl acetate. In some embodiments, a solvent comprises an alcohol. In certain embodiments, a solvent comprises ethanol. In some embodiments, a solvent comprises an alkyl acetate and an alcohol, for instance ethyl acetate and ethanol. In certain embodiments, wherein a solvent comprises ethanol, at least one other solvent (e.g., ethyl acetate) is present. In certain embodiments, continuous vacuum distillation is performed until a desired solvent volume or composition is achieved.

[00199] In some embodiments, salt formation does not comprise a first step of pretreating Compound I. For instance, in certain embodiments, Compound I is dissolved in a suitable solvent and treated directly with acid. In some embodiments, a solvent comprises a polar aprotic solvent such as an alkyl acetate. In certain embodiments, the solvent is ethyl acetate. In some embodiments, the solvent is isopropyl acetate. In certain embodiments, a solvent comprises an alcohol. In some embodiments, a solvent comprises ethanol. In some embodiments, a solvent comprises an alkyl acetate and an alcohol, for instance ethyl acetate and ethanol. In certain embodiments, wherein such a solvent comprises ethanol, at least one other solvent (e.g., ethyl acetate) is present.

[00200] In some embodiments, a solution of free base Compound I is seeded with an amount of crystalline Compound I prior to salt formation. For instance, in some embodiments, seeding occurs with a particular polymorph of a salt form of Compound I. In certain embodiments, seeding occurs with a particular polymorph of a phosphate salt form of Compound I. For example, in some embodiments, seeding occurs with polymorph Form A of a phosphate salt form of Compound I. Polymorph Form A of a phosphate salt of Compound I is as described below and as described in United States Provisional Application No. 62/037,066, filed August 13, 2014, incorporated herein in its entirety.

[00201] In some embodiments, a suitable acid for forming a salt of Compound I is dissolved in a suitable solvent prior to addition to Compound I. For instance, in some embodiments, an acid is dissolved in an alcoholic solvent prior to addition to Compound I. In certain embodiments, the acid is phosphoric acid (H₃PO₄) and the alcoholic solvent is ethanol.

[00202] In some embodiments, the acid of step S-5 (e.g., H₃PO₄) is added to the reaction mixture over a period of time. In some embodiments, addition to the reaction mixture occurs while the reaction mixture is held at a particular temperature. For instance, in some embodiments, addition to the reaction mixture occurs at a temperature of about 20 °C to about 40 °C for about 60, 70, 80, 90, 100, 110, 120, 125, 130, 135, 140, 145, 150, 155, 160, 165, 170, 175, or 180 minutes. In some embodiments, addition to the reaction mixture occurs for between about 90 and about 150 minutes. In some embodiments, addition to the reaction mixture occurs for about 120 minutes.

[00203] In some embodiments, the reaction is agitated for at least about 6, 7, 8, 9, 10, 11, 12,

13, 14, 15, 16, 17, or 18 hours. In certain embodiments, the reaction is agitated for about 10 to about 14 hours. In some embodiments, the reaction is agitated for about 12 hours.

[00204] In some embodiments, the precipitate is filtered, washed with an organic solvent (e.g., a polar aprotic solvent such as ethyl acetate), and dried to afford a salt of Compound I.

[00205] In certain embodiments, the above described methods are used to produce a phosphate salt of Compound I, depicted below:

H

[00206] It is contemplated that a phosphate salt of compound I can exist in a variety of physical forms. For example, a phosphate salt of compound I can be in solution, suspension, or in solid form. In certain embodiments, a phosphate salt of compound I is in solid form. When a phosphate salt of compound I is in solid form, said compound may be amorphous, crystalline, or a mixture thereof. Exemplary solid forms are described in more detail below.

[00207] In some embodiments, methods of the present invention provide a phosphate salt of Compound I in a particular polymorphic form. In some embodiments, methods of the present invention use a particular form of a phosphate salt of Compound I for seeding, for instance as described above in the context of the step of salt formation. In certain embodiments, Form A of a phosphate salt of Compound I is used for seeding. In some embodiments, methods of the present invention provide Form A of a phosphate salt of Compound I, described herein.

Form A of a Phosphate Salt of Compound I

[00208] In some embodiments, Form A of a phosphate salt of Compound I has at least 1, 2, 3, 4 or 5 spectral peak(s) selected from the peaks listed in Table 5 below.

Table 5 - XRPD Peak Positions for Form A of a Phosphate Salt of Compound I

¹ In this and al subsequent tables,

the position 2 Θ is within ± 0.2.

[00209] In some embodiments, Form A of a phosphate salt of Compound I is characterized in that it has one or more peaks in its X-ray powder diffraction pattern selected from those at about 6.8, 10.1, and 20.8. In some embodiments, Form A of a phosphate salt of Compound I is characterized in that it has two or more peaks in its X-ray powder diffraction pattern selected from those at about 6.8, 10.1, and 20.8. In some embodiments, Form A of a phosphate salt of Compound I is characterized in that it has all three peaks in its X-ray powder diffraction pattern selected from those at about 6.8, 10.1, and 20.8.

[00210] In certain embodiments, the X-ray powder diffraction pattern of Form A of a phosphate salt of Compound I is substantially similar to the XRPD provided in Figure 9.

[00211] In certain embodiments, the DSC thermogram of Form A of a phosphate salt of Compound I is as depicted in Figure 10.

[00212] In certain embodiments, the TGA trace of Form A of a phosphate salt of Compound I is as depicted in Figure 11.

[00213] In certain embodiments, the DVS plot of Form A of a phosphate salt of Compound I is as depicted in Figure 12.

[00214] Methods for preparing Form A of a phosphate salt of Compound I are described infra.

Alternative Methods for Preparing a Phosphate Salt of Compound I

[00215] In some embodiments, the present invention provides methods of salt formation / crystallization that generate crystals having certain physical properties, which properties facilitate product processing. For example, in some embodiments, the present invention provides crystallization methods that generate crystals having certain flow properties. In some embodiments, the present invention provides crystallization methods that generate crystals having reduced stickiness for ease of product processing. In some embodiments, crystals are generated in the form of thin plates. In certain embodiments, the crystals are Form A of the phosphate salt of Compound I.

[00216] In some embodiments, a provided method comprises charging a portion of the total final mass of free base Compound I to a reactor, along with an amount of solvent comprising one or more polar organic solvents (e.g., ethyl acetate and ethanol). In some embodiments, the portion of free base charged is about 5% to about 40% of the total final mass of free base Compound I. In some embodiments, the portion of free base charged is about 10% to about 30% of the total final mass of free base Compound I. In some embodiments, the portion of free base charged is about 15% to about 25% of the total final mass of free base Compound I. In some embodiments, the portion of free base charged is about 20% of the total final mass of free base Compound I. Alternatively, in some embodiments, 100% of the total final mass of free base Compound I is initially charged. In some embodiments, the solvent comprising one or more polar organic solvents is a mixture of ethyl acetate and ethanol, wherein the ethyl acetate is present in an amount greater than the ethanol. In some embodiments, the ratio of ethyl acetate to ethanol is about 13:5 vol. ethyl acetate: ethanol.

[00217] In some embodiments, the mixture of free base Compound I and organic solvent is agitated for an amount of time at a suitable temperature. For example, in some embodiments, agitation is initiated and the temperature is raised to between about 20 °C and about 40 °C. In some embodiments, agitation is initiated and the temperature is raised to between about 25 °C and about 35 °C. In some embodiments, agitation is initiated and the temperature is raised to about 30 °C.

[00218] In some embodiments, a solution of phosphoric acid in organic solvent is prepared for addition to the reaction undergoing agitation. In certain embodiments, a solution of phosphoric acid comprises one or more polar organic solvents. In some embodiments, the one or more polar organic solvents comprises ethyl acetate. In some embodiments, the one or more polar organic solvents comprises ethanol, In some embodiments, the one or more polar organic solvents is a mixture of ethyl acetate and ethanol, wherein the ethyl acetate is present in an amount greater than the ethanol. In some embodiments, the ratio of ethyl acetate to ethanol is about 13:5 vol. ethyl acetate : ethanol. In some embodiments, phosphoric acid is present in an amount of about 1.0, 1.1, 1.2, 1.3, or 1.4 molar equivalents relative to substrate (i.e., free base Compound I). In some embodiments, phosphoric acid is present in an amount of about 1.2 molar equivalents relative to substrate (i.e., free base Compound I).

[00219] In some embodiments, a first portion of the solution of phosphoric acid is charged to the reactor over an amount of time. For example, in some embodiments, about 10% to about 30%) of the solution of phosphoric acid is charged to the reactor over about 10 minutes to about 30 minutes. In some embodiments, about 20%> of the solution of phosphoric acid is charged to the reactor over about 10 minutes to about 30 minutes. In some embodiments, about 20%> of the solution of phosphoric acid is charged to the reactor over about 20 minutes.

[00220] In some embodiments, after addition of a first portion of the solution of phosphoric acid is completed, an amount of crystal seeds of a phosphate salt of Compound I (e.g., Form A of the phosphate salt of Compound I) is charged to the reaction and the batch is aged for an amount of time. In some embodiments, about 1% (by wt) crystal seeds are charged. In some embodiments, about 2% (by wt) crystal seeds are charged. In some embodiments, about 3% (by wt) crystal seeds are charged. In some embodiments, about 4, 5, 6, 7, 8, 9, or 10% (by wt) crystal seeds are charged. In some embodiments, the batch is then aged for about 5 minutes to about 60 minutes. In some embodiments, the batch is aged for about 15 minutes to about 45 minutes. In some embodiments, the batch is aged for about 20 minutes to about 40 minutes. In some embodiments, the batch is aged for about 30 minutes.

[00221] In some embodiments, following aging of the reaction, one or more heat-cool cycles are conducted. As used herein, the phrase "heat-cool cycle" refers to the process of alternately heating and cooling a reaction mixture to desired temperatures at desired rates.

[00222] In some embodiments 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, or 20 heat-cool cycles are conducted. In some embodiments 8, 9, 10, 11, or 12 heat-cool cycles are conducted. In some embodiments, 10 heat-cool cycles are conducted.

[00223] In some embodiments, the heat-cool cycles are carried out at a temperature of between about 10 °C to about 50 °C. In some embodiments, the heat-cool cycles are carried out at a temperature of between about 20 °C to about 40 °C. In some embodiments, at least one heat-cool cycle is carried out at a different temperature range than another heat-cool cycle. In some embodiments, at least one heat-cool cycle is carried out at a temperature of between about 30 °C to about 40 °C. In some embodiments, at least one heat-cool cycle is carried out at a temperature of between about 20 °C to about 30 °C.

[00224] In some embodiments, heating occurs at a rate of about 0.1 °C/min, 0.2 °C/min, 0.3

°C/min, 0.4 °C/min, 0.5 °C/min, 0.6 °C/min, 0.7 °C/min, 0.8 °C/min, 0.9 °C/min, or about 1.0

°C/min. In certain embodiments, heating occurs at a rate of about 0.4 °C/min, 0.5 °C/min, or 0.6

°C/min. In certain embodiments, heating occurs at a rate of about 0.5 °C/min.

[00225] In some embodiments, cooling occurs at a rate of about 0.1 °C/min, 0.2 °C/min, 0.3

°C/min. In certain embodiments, cooling occurs at a rate of about 0.1 °C/min.

[00226] In some embodiments, the remaining starting material free base Compound I is added to the reaction following completion of one or more heat-cool cycles, along with the remaining solution of phosphoric acid. In some embodiments, the solution of phosphoric acid is charged over at least about 1.5 hours. In some embodiments, the solution of phosphoric acid is charged over about 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, or 24 hours. In some embodiments, the charge occurs at an elevated temperature. For instance, in some embodiments, the charge occurs at about 30 °C. In some embodiments, the reaction is held at an elevated temperature and agitated for about 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, or 20 hours. In some embodiments, the reaction is held at an elevated temperature and agitated for about 12, 24, 36, or 48 hours. In certain embodiments, the reaction is held at an elevated temperature and agitated for about 12 hours. In some embodiments, the elevated temperature is between about 20 °C and about 40°C. In some embodiments, the elevated temperature is about 30 °C. For instance, in some embodiments, the reaction is held at about 30 °C and agitated for about 12 hours.

[00227] In some embodiments, after agitation for a suitable amount of time the reaction is cooled, filtered, washed, dried under reduced pressure, and de-lumped. In some embodiments, the reaction is cooled after agitation to between about 15 °C and about 35 °C. In some embodiments, the reaction is cooled after agitation to between about 15 °C and about 30 °C. In some embodiments, the reaction is cooled after agitation to between about 20 °C and about 25 °C. In some embodiments, the reaction is cooled after agitation to about 23 °C. In some embodiments, after cooling the reaction after agitation, the reaction is filtered and washed one or more times with a suitable solvent (e.g., an organic solvent). For instance, in some embodiments, the reaction is filtered and washed one or more times with a polar aprotic solvent such as ethyl acetate. In some embodiments, the reaction is filtered and washed twice with a polar aprotic solvent such as ethyl acetate. In some embodiments, the product is then dried under reduced pressure with a nitrogen bleed. In some embodiments, drying occurs at a temperature of between about 30 °C and about 60 °C. In some embodiments, drying occurs at a temperature of between about 35 °C and about 55 °C. In some embodiments, drying occurs at a temperature of between about 40 °C and about 50 °C. In some embodiments, the dried product is then de- lumped using any method known in the pharmaceutical and/or process chemistry arts.

[00228] In some embodiments, methods described herein provide a crystalline form of a phosphate salt of Compound I, e.g., Form A of the phosphate salt of Compound I, which crystalline form exhibit certain desirable properties, e.g., a desirable size or shape. [00229] In some embodiments, the present invention provides a method for preparing Compound I:

or a pharmaceutically acceptable salt thereof, comprising steps of:

(a) providing compound F:

(b) reacting compound F with a suitable amine protecting group to provide a compound of formula E:

;

wherein PG¹ is a suitable amine protecting group;

(c) coupling a compound of formula E to a compound of formula D:

wherein each of LG¹ and LG² is independently a suitable leaving group, under suitable conditions to provide a compound of formula C:

(d) coupling a compound of formula C to compound B:

under suitable conditions to form a compound of formula A:

(e) deprotecting a compound of formula A under suitable conditions to provide

Compound I, or a pharmaceutically acceptable salt thereof.

[00230] In some embodiments, the present invention provides a method for preparing a pharmaceutically acceptable salt of Compound I:

wherein:

HX is any suitable acid comprising at least one hydrogen atom. [00231] For instance, in some embodiments, the present invention provides a method for preparing a pharmaceutically acceptable salt of Compound I:

wherein:

HX is any suitable acid comprising at least one hydrogen atom;

comprising steps of:

(a) providing Compound I:

(b) reacting Compound I with a suitable acid to provide a pharmaceutically acceptable salt of Compound I.

[00232] In some embodiments, the present invention provides a method for preparing a phosphate salt of Compound I, comprising steps of:

(a) providing a first portion of free base Compound I:

H

(b) exposing the first portion of free base Compound I to a first portion of phosphoric acid;

(c) adding to the resulting mixture seed crystals of a phosphate salt of Compound I;

(d) performing one or more heat-cool cycles on the mixture;

(d) providing an additional portion of free base Compound I to the mixture; and;

(e) exposing the mixture to an additional portion of phosphoric acid under suitable conditions to form an additional amount of phosphate salt of Compound I.

Methods of Making Compound B

[00233] In some embodiments, compound B, or a salt thereof, is prepared according to Scheme II set forth below:

Scheme II

[00234] In Scheme II above, PG is as defined below and in classes and subclasses as described herein.

[00235] In some embodiments, compound B is produced according to Scheme II in the form of the HC1 salt.

[00236] At step S-1 of Scheme II, the amine group of commercially available compound B-4 is protected to afford a compound of formula B-3. [00237] The PG group of a compound of formula B-3 is a suitable amino protecting group. Suitable amino protecting groups are well known in the art and include those described in detail in Protecting Groups in Organic Synthesis, T. W. Greene and P. G. M. Wuts, 3^rd edition, John Wiley & Sons, 1999, the entirety of which is incorporated herein by reference. Suitable amino protecting groups, taken with the - H- moiety to which it is attached, include, but are not limited to, aralkylamines, carbamates, allyl amines, amides, and the like. Examples of PG³ groups of a compound of formula B-3 include t-butyloxycarbonyl (BOC),p-methoxybenzyloxycarbonyl (PMB), ethyloxycarbonyl, methyloxycarbonyl, trichloroethyloxycarbonyl, allyloxycarbonyl (Alloc), benzyl oxocarbonyl (CBZ), allyl, benzyl (Bn), fluorenylmethylcarbonyl (Fmoc), acetyl, chloroacetyl, dichloroacetyl, formyl, trichloroacetyl, phenylacetyl, trifluoroacetyl, benzoyl, and the like.

[00238] In some embodiments, the PG³ group of a compound of formula B-3 is formyl. In certain embodiments, the PG³ group of a compound of formula B-3 is formyl and the reagent used to generate PG³ is formic acid. In certain embodiments, the PG³ group of a compound of formula B-3 is formyl and the reagent used to generate PG³ is an alkyl formate (e.g., ethyl formate). Other such formylating reagents are known in the chemical and synthetic arts and are contemplated herein.

[00239] In some embodiments, the PG³ group of a compound of formula B-3 is BOC. In some such embodiments, the reagent used to generate PG³ is di-tert-butyl dicarbonate.

[00240] In some embodiments, step S-1 is conducted in a solvent comprising an organic solvent. In some embodiments, step S-1 is conducted neat. For instance, in some embodiments, the protecting group reagent (e.g., formic acid or an equivalent thereof) acts as the solvent.

[00241] In some embodiments, step S-1 is conducted at elevated temperatures. For instance, in some embodiments, step S-1 is conducted at a temperature between about 25 °C and about 75 °C. In some embodiments, the temperature is between about 30 °C and about 70 °C. In some embodiments, the temperature is between about 40 °C and about 90 °C. In some embodiments, the temperature is between about 65 °C and about 60 °C. In some embodiments, the temperature is between about 45 °C and about 65 °C. In some embodiments, the temperature is about 50 °C.

[00242] In some embodiments, the reaction is heated for at least about 1, 2, 3, 4, 5, 6, 7, 8, 9, or 10 hours. In some embodiments, the reaction is heated for between about 4 and about 6 hours. In certain embodiments, the reaction is heated for about 5 hours. [00243] In some embodiments, after heating for an amount of time, the reaction is cooled to between about 15 °C and about 20 °C and charged to an amount of water. In certain embodiments, addition to water takes place in portions over an amount of time. For instance, in some embodiments, addition to water occurs over about 30, 45, 60, 75, or 90 minutes. In certain embodiments, addition to water occurs over about 60 minutes. In some embodiments, the resulting slurry is agitated for an additional amount of time after addition of water. For instance, in some embodiments, the resulting slurry is agitated for about 1, 2, or 3 hours. In certain embodiments, the resulting slurry is agitated for about 2 hours. In certain embodiments, the temperature of the slurry is maintained at about 15 °C during agitation.

[00244] In certain embodiments, upon reaction completion, the slurry is filtered, washed with an amount of solvent (e.g., 1 : 1 formic acid:water), washed with water, and dried (e.g., under reduced pressure at about 45 °C) to afford a compound of formula B-3. In some embodiments, a compound of formula B-3 is compound 11:

11

[00245] At step S-2 of Scheme II, the nitro group of B-3 is reduced to afford a compound of formula B-2.

[00246] In some embodiments, reduction of the nitro group of B-3 to the amine of B-2 occurs in the presence of a suitable reducing agent (e.g., Pd/C) in a suitable solvent. Exemplary other such reducing agents are known in the art, for instance, see Comprehensive Organic Transformaions, R. C. Larock, 2nd Edition, John Wiley & Sons, 1999, pages 823-827. In some embodiments, a solvent comprises an ether. For instance, in some embodiments, a solvent comprises tetrahydrofuran (TUF). In some embodiments, a solvent comprises water. In certain embodiments, a solvent comprises water and an ether (e.g., water and TUF).

[00247] In some embodiments, step S-2 occurs under a hydrogen atmosphere. In certain embodiments, step S-2 is initiated under a hydrogen atmosphere of between about 5 psi and about 20 psi. In certain embodiments, step S-2 is initiated at about 5, 10, 15, or 20 psi. [00248] In some embodiments, step S-2 is exothermic and is initiated at a temperature of no more than about 60 °C. In some embodiments, step S-2 is initiated at a temperature of no more than about 50 °C. In some embodiments, step S-2 is initiated at a temperature of no more than about 40 °C.

[00249] In some embodiments, after initiation of the reaction, the pressure of the hydrogen atmosphere is increased. For instance, in some embodiments, the pressure of the hydrogen atmosphere is increased to about 25, 30, 35, 40, 45, or 50 psi for a particular amount of time and at a particular temperature, until conversion of B-3 to B-2 is complete. In certain embodiments, the pressure of the hydrogen atmosphere is increased to between about 30 and about 40 psi for about 3 hours at about 50 °C.

[00250] In some embodiments, upon reaction completion, the hydrogen atmosphere is exchanged for an inert atmosphere (e.g., nitrogen) and the reaction is cooled to between about 20 °C to about 30 °C. In some such embodiments, the reaction is filtered (e.g., through Celite) and the cake is washed with additional solvent (e.g., 13:2 THF:water).

[00251] In some embodiments, a compound of formula B-2 is compound 12:

12

[00252] In some embodiments, the resulting solution of B-2 is taken on without isolation or purification. For instance, in some embodiments, at step S-3 of Scheme II, the resulting solution of B-2 (e.g., in TUF and water), is charged to a separate solution comprising a base. In certain embodiments, the base is a carbonate base such as lithium carbonate, sodium carbonate, or potassium carbonate. In certain embodiments, the solution of base is aqueous potassium carbonate. Various other bases, for instance hydroxide bases, alkoxide bases, amine bases, amide bases, etc. are known in the art and contemplated herein for use in step S-3.

[00253] In some embodiments, B-2 is isolated prior to exposure to base.

[00254] In some embodiments, the solution of base and B-2 is cooled prior to addition of acryloyl chloride. In certain embodiments, the solution of base (e.g., aqueous potassium carbonate) and B-2 is cooled to between about 0 °C and about 10 °C prior to addition of acryloyl chloride. In some embodiments, addition of acryloyl chloride occurs over an amount of time at reduced temperatures. For instance, in some embodiments, addition of acryloyl chloride occurs over about 5, 10, 15, 20, 25, 30, 35, 40, 45, 50, 55, or 60 minutes at a temperature no higher than about 10 °C. In certain embodiments, addition of acryloyl chloride occurs over about 30 minutes at a temperature no higher than about 10 °C.

[00255] In some embodiments, after addition is complete, the reaction is held at reduced temperature (e.g., between about 5 °C and about 10 °C) for a period of time (e.g., about 30 minutes), warmed (e.g., to about 25 °C), and diluted with an amount of solvent. In some embodiments, the solvent is an ethereal solvent (e.g., THF). In certain embodiments, after addition of solvent, the reaction is allowed to settle and the aqueous layer is removed. In some embodiments, the volume of solvent is reduced (e.g., by vacuum distillation) prior to further work up. In certain embodiments, once a particular solvent volume or composition is achieved (e.g., via distillation), an amount of water is added to the solution of acrylate B-l and stirred at a slightly elevated temperature (e.g., about 35 °C) until B-l crystallizes out of solution. In some embodiments, the resulting slurry of crystallized B-l is then cooled (e.g., to about 25 °C), agitated for an amount time (e.g., about 3 hours), filtered, washed with solvent (e.g., 1 :2 THF:water) and dried (e.g., under reduced pressure) to afford B-l.

[00256] In some embodiments, a compound of formula B-l is compound 13:

13

[00257] At step S-4 of Scheme II, the protected amine group of B-l is deprotected to afford compound B, or an acceptable salt thereof.

[00258] In some embodiments, deprotection of B-l requires treatment of B-l with an acid. For instance, in some embodiments, B-l is slurried in a suitable solvent and an acid is slowly added over an amount of time at a reduced temperature. In certain embodiments, a suitable solvent comprises an alcohol (e.g., methanol). In certain embodiments, a suitable solvent comprises an ether (e.g., methyl tert-butyl ether). In certain embodiments, a suitable solvent comprises an alcohol and an ether (e.g., methanol and methyl tert-butyl alcohol). In some embodiments, the acid is an inorganic acid (e.g., HC1). In certain embodiments, the inorganic acid is an aqueous inorganic acid (e.g., 36% HC1). In certain embodiments, addition occurs over about 5, 10, 15, 20, 25, 30, 35, 40, 45, 50, 55, or 60 minutes. In certain embodiments, addition occurs between about 20 minutes and about 40 minutes. In certain embodiments, addition occurs over about 30 minutes. In some embodiments, addition occurs at reduced temperatures. For instance, in some embodiments, addition occurs at temperatures below about 25 °C. In some embodiments, addition occurs at temperatures between about 15 °C and about 25 °C. In some embodiments, after addition of the acid (e.g., HQ), the reaction is heated and agitated for an amount of time. In some embodiments, the reaction is heated and agitated for about 1, 2, 3, 4, 5, 6, 7, 8, 9, or 10 hours. In certain embodiments, the reaction is heated to between about 20 °C and about 25 °C and agitated for between about 4 hours and about 6 hours. In certain embodiments, the reaction is agitated for about 5 hours. In certain embodiments, additional solvent is added to the agitated reaction. For instance, in certain embodiments, the additional solvent is an ether (e.g., methyl tert-butyl ether). In certain embodiments, after the addition of solvent, the reaction is agitated for an additional amount of time (e.g., about 1 hour), the filtered, washed with solvent (e.g., 1 :2 methanol :methyltert-butyl ether), and dried (e.g., under reduced pressure) to afford compound B in salt form. In some embodiments, compound B is provided as the HC1 salt. One of skill in the chemical and synthetic arts will appreciate that a variety of acids can be used to achieve compound B in salt form and are contemplated herein.

[00259] In some embodiments, a salt form of compound B is exposed to an amount of base in order to afford compound B as the free base. For instance, in some embodiments, compound B is added to an aqueous base and stirred to afford the free base of compound B. In certain embodiments, the base is a hydrogen carbonate base such as LiHCO₃, NaHCO₃, or KHCO3. In certain embodiments, the solution of base is aqueous NaHCO₃.

[00260] In some embodiments, the present invention provides a method for preparing compound B:

salt thereof, comprising steps of:

(a) providing compound B-4:

(b) reacting the free amine of compound B-4 with a suitable protecting group under suitable conditions to provide a compound of formula B-3:

wherein PG³ is a suitable amine protecting group;

(c) reducing the nitro group of a compound of formula B-3 under suitable conditions to provide a compound of formula B-2:

(d) treating a compound of formula B-2 with acryloyl chloride under suitable conditions to provide a compound of formula B-l:

(e) deprotecting a compound of formula B-l under suitable conditions to provide compound B or a salt thereof.

[00261] Alternatively, in some embodiments, compound B, or a salt thereof, is prepared according to Scheme III set forth below: Scheme III

[00262] In some embodiments, compound B is produced according to Scheme III in the form of the HC1 salt.

[00263] At step S-1 of Scheme III, the amine of compound B-12 is reacted with 3- chloropropionyl chloride to afford amide B-5. In some embodiments, amide B-5 acts as a protecting group and precursor to the acrylamide of compound B. In some embodiments, step S- 1 occurs in a suitable solvent in the presence of a base. For instance, in certain embodiments, the base is a carbonate base such as Li₂CO₃, Na₂CO₃, or K₂CO₃. In certain embodiments, the base is

K₂CO₃.

[00264] At step S-2 of Scheme III, the nitro group of B-5 is reduced to the corresponding amine of B-6. In some embodiments, reduction occurs as described above at step S-2 of Scheme II. In some embodiments, other reduction conditions are employed. Various other such reducing agents are known in the chemical and synthetic arts and are contemplated herein.

[00265] At step S-3 of Scheme III, elimination of HC1 affords the acrylate of compound B. In some embodiments, elimination occurs in the presence of a suitable base.

[00266] One of skill in the chemical and synthetic arts will recognize that step S-3 is potentially performed during any point in the synthesis. Accordingly, in some embodiments, step S-3 is not performed directly after step S-2. That is, in some embodiments, B-6 acts as the coupling partner at step S-3 of Scheme I, and step S-3 of Scheme III is performed at a different point during the synthesis of Compound I, for instance, any time during the synthesis up to the last step. [00267] In some embodiments, the present invention provides a method for preparing compound B:

or a salt thereof, comprising steps of:

(a) providing compound B-12:

(b) reacting the free amine of compound B-12 under suitable conditions in the presence of 3-chloropropionyl chloride to provide compound B-5:

(c) reducing compound B-5 under suitable conditions to provide compound B-6:

(d) contacting compound B-6 with a suitable base under suitable conditions to provide compound B or a salt thereof.

[00268] Alternatively, in some embodiments, compound B, or a salt thereof, is prepared according to Scheme IV set forth below: Scheme IV

[00269] In some embodiments, compound B is produced according to Scheme IV in the form of the HC1 salt.

[00270] At step S-1 of Scheme IV, the amine of compound B-12 is reacted with acryloyl chloride to afford acrylamide B-7. In some embodiments, step S-1 occurs in a suitable solvent in the presence of a base. In certain embodiments, a suitable solvent is a polar aprotic solvent such as an alkyl acetate (e.g., ethyl acetate). In certain embodiments, the base is a carbonate base such as L12CO3, Na₂C03, or K2CO3. In certain embodiments, the base is K2CO3.

[00271] At step S-2 of Scheme IV, B-7 is exposed to methanol in the presence of a suitable base to provide B-8. In certain embodiments, the base is a hydroxide base. For instance, in some embodiments, the base is LiOH, NaOH, or KOH. In certain embodiments, the base is NaOH.

[00272] At step S-3 of Scheme IV, the nitro group of B-8 is reduced to the corresponding amine of B-9. In some embodiments, reduction occurs as described above at step S-2 of Scheme II. In some embodiments, other reduction conditions are employed. Various other such reducing agents are known in the chemical and synthetic arts and are contemplated herein.

[00273] At step S-4 of Scheme IV, elimination of MeOH affords acrylamide compound B. In some embodiments, elimination occurs in the presence of a base. In certain embodiments, the base is an alkoxide base such as a lithium, sodium, or potassium alkoxide. In certain embodiments, the alkoxide base is t-BuOLL t-BuONa, or t-BuOK. [00274] In some embodiments, the present invention provides a method for preparing compound B:

or a salt thereof, comprising steps of:

(a) providing compound B-12:

(b) reacting the free amine of compound B-12 under suitable conditions in the presence of acryloyl chloride to provide compound B-7:

(c) exposing compound B-7 to methanol under suitable conditions to provide compound 8:

(d) reducing compound B-8 under suitable conditions to provide compound B-9:

(e) contacting compound B-9 with a suitable base under suitable conditions to provide compound B or a salt thereof.

[00275] Alternatively, in some embodiments, compound B, or a salt thereof, is prepared according to Scheme V set forth below:

Scheme V

[00276] In some embodiments, compound B is produced according to Scheme V in the form of the HC1 salt.

[00277] At step S-1 of Scheme V, the amine of compound B-10 is reacted with acryloyl chloride to non-selectively afford, inter alia, compound B. Purification to remove, inter alia, the monoacrylate and/or bisacrylate byproducts depicted below:

affords the desired compound B or a salt thereof. [00278] In some embodiments, the present invention provides a method for preparing compound B:

or a salt thereof, comprising steps of:

(a) providing compound B-10:

(b) reacting compound B-10 under suitable conditions in the presence of acryloyl chloride to provide compound B or a salt thereof.

[00279] Alternatively, in some embodiments, compound B, or a salt thereof, is prepared according to Scheme VI set forth below:

Scheme VI

[00280] Alternatively, in some embodiments, compound B', or a salt thereof, is prepared according to Scheme VI' set forth below:

Scheme VI'

wherein each of R¹ and R² are independently hydrogen or a suitable amino protecting group described above and herein. As described above, one of skill in the art would appreciate that various methods and conditions for protecting amines are known in the chemical arts. For example, suitable amino protecting groups include those described in detail in Protecting Groups in Organic Synthesis, T. W. Greene and P. G. M. Wuts, 3^rd edition, John Wiley & Sons, 1999, the entirety of which is incorporated herein by reference.

[00281] In Scheme VI and Scheme VI', above, LG³ is a suitable leaving group as defined above and herein for LG¹ and LG². In some embodiments, LG³ is selected from chloro, iodo, bromo, fluoro, sulfoxide, sulphone, methanesulfonyloxy, tosyloxy, triflyloxy, benzenesulfonyloxy, nitro-phenylsulfonyloxy, and bromo-phenylsulfonyloxy.

[00282] In some embodiments, compound B is produced according to Scheme VI in the form of the HC1 salt.

[00283] In some embodiments, compound B' is produced according to Scheme VI' in the form of the HC1 salt.

[00284] At step S-1 of Scheme VI, compound B-ll is coupled to acrylamide to afford acrylamide B. In some embodiments, coupling occurs in the presence of one of more suitable catalysts, for instance one or more metal catalysts. In certain embodiments, a catalyst is Pd. In certain embodiments, a catalyst is Cu. Various other such metal reagents are known in the chemical and synthetic arts and are contemplated herein.

[00285] In some embodiments, the present invention provides a method for preparing compound B:

or a salt thereof, comprising steps of:

(a) providing a compound of formula B-ll:

wherein LG³ is a suitable leaving group; and

(b) coupling a compound of formula B-ll under suitable conditions in the presence of acrylamide to provide compound B or a salt thereof. Compositions Comprising Compound I

[00286] In some embodiments, the present invention provides a composition comprising Compound I:

Compound I

or a pharmaceutically acceptable salt thereof, and at least one compound selected from Table 6, below, or a pharmaceutically acceptable salt thereof.

Table 6.

N OMe

1-13

(E or Z).

[00287] One of skill in the art will recognize that the "(E or Z)" designation in Table 6, above, means that the depicted structure contemplates both the E isomer and the Z isomer. For instance, each of 1-11, 1-12, and 1-13 are contemplated in either isomeric form, i.e., the E or Z configuration.

Uses of Compounds and Pharmaceutically Acceptable Compositions Prepared Using Methods of the Present Invention

[00288] As described generally above, Compound I, and pharmaceutically acceptable salts thereof described herein, are inhibitors of one or both of ERK1 and ERK2. One of ordinary skill in the art will recognize that ERK is one of the key components in the RAS-RAF-MEK-ERK MAPK pathway and that ERK1 and ERK2 are downstream nodes within the MAPK pathway. Without wishing to be bound by theory, because of the downstream location of ERK1 and ERK1 in the MAPK pathway, an ERK inhibitor can treat disease or disorders in which activation of the MAPK pathway at any level (Ras-Raf-Mek-ERK) is known or suspected to play a role, including one or both of ERK 1 and ERK2 as well as other nodes in the MAPK pathway upstream from ERK (such as Ras, Raf and Mek). Furthermore, because ERK is a downstream target, ERK inhibitors are believed to be able to overcome, in some instances, drug resistance induced by inhibitors of targets upstream of ERK within the MAPK pathway. For example, small molecule inhibitors of RAF or MEK utilized in the treatment of K-RAS and B-RAF mutant tumors have resulted in such drug resistance. Similarly, drug resistance has been associated with other tumors driven by hyperactivation of the MAPK pathway (such as NF1 mutant tumors). Kinase selectivity was achieved through silencing the selective Cys in a combination of the interactions between the covalent inhibitors of the invention and unique amino acids in the ATP binding pocket. Targeting the selective Cys provides for prolonged pharmacodynamics in silencing ERK activity, as well as potential lower doses in cancer treatment, compared to reversible inhibitors.

[00289] The activity of Compound I, and pharmaceutically acceptable salts thereof, as inhibitors of one or both of an ERK1 and ERK2 kinase, or a mutant thereof, may be assayed in vitro, in vivo or in a cell line. In vitro assays include assays that determine inhibition of downstream phosphorylation, changes in gene expression, subsequent functional markers and consequences, and/or kinase activity of one or both of activated ERK1 and ERK2 kinase, or a mutant thereof. Alternate in vitro assays quantitate the ability of the test compound to bind to one or both of ERK1 and ERK2. Test compound binding may be measured by radiolabeling the test compound prior to binding, isolating one or both of the compound / ERK1 complex and the compound / ERK2 complex, and determining the amount of radiolabel bound. Alternatively, test compound binding may be determined by running a competition experiment where test compounds are incubated with one or both of ERK1 and ERK2 kinase bound to known radioligands. Test compound binding may be determined by competition with an ERK covalent probe that is amenable to further functionalization with a detection probe, such as, for example, a fluorophore, biotin conjugate, radiolabel, or any other probe that facilitates its quantification. Detailed conditions for assaying a compound utilized in this invention as an inhibitor of one or both of ERK1 and ERK2, or a mutant thereof, are also set forth below and/or in the Examples of the '230 publication.

[00290] The term "measurably inhibit", as used herein means a measurable change in one or both of ERKl and ERK2 protein kinase activity between a sample comprising a provided composition, and one or both of an ERKl and ERK2 protein kinase and an equivalent sample comprising one or both of ERKl and ERK2 protein kinase in the absence of a provided composition. Such measurements of protein kinase activity are known to one of ordinary skill in the art and include those methods set forth herein below and/or in the Examples of the '230 publication.

[00291] As described above, in some embodiments, Compound I, and pharmaceutically acceptable salts thereof, as inhibitors of one or both of ERKl and ERK2 protein kinases, and ERK1 and ERK2 are downstream targets within the MAPK pathway. Without wishing to be bound by any particular theory, such compounds and compositions are particularly useful for treating or lessening the severity of a disease, condition, or disorder in which activation of the MAPK pathway at any level (Ras-Raf-Mek-ERK) is known or suspected to play a role. Such disease, condition, or disorder may be referred to herein as associated with the MAPK pathway or alternatively as associated with one or both of ERKl and ERK2. Such diseases, conditions, or disorders may also be referred to herein as an "ERKl- or ERK2-mediated disease, condition, or disorder."

[00292] In some embodiments, the present invention provides methods of making compounds useful for treating or lessening the severity of a disease, condition, or disorder where activation of the MAPK pathway (at any level in Ras-Raf-Mek-ERK), including one or both of ERKl and ERK2 protein kinases, is implicated in said disease, condition, or disorder.

[00293] In some embodiments, the present invention provides methods of making compounds useful for inhibiting one or both of ERKl and ERK2 protein kinase activity in a patient.

[00294] In other embodiments, the present invention provides methods of making compounds useful for treating a disease, condition, or disorder mediated by one or both of ERKl and ERK2 kinase, or a mutant thereof.

[00295] In certain embodiments, the present invention provides methods of making compounds useful for overcoming drug resistance to Raf or MEK inhibitors. In certain embodiments, the mechanism of drug resistance is through mutation of a target protein or reactivation of the MAPK pathway.

[00296] As used herein, the term "resistance" may refer to changes in a wild-type nucleic acid sequence coding a target protein, and/or to the amino acid sequence of the target protein and/or to the amino acid sequence of another protein, which changes, decreases or abolishes the inhibitory effect of the inhibitor on the target protein. The term "resistance" may also refer to overexpression or silencing of a protein differing from a target protein that can reactivate the MAPK pathway or other survival pathways.

[00297] As used herein, the terms "treatment," "treat," and "treating" refer to reversing, alleviating, delaying the onset of, or inhibiting the progress of a disease or disorder, or one or more symptoms thereof, as described herein. In some embodiments, treatment is administered after one or more symptoms have developed. In other embodiments, treatment is administered in the absence of symptoms. For example, treatment is administered to a susceptible individual prior to the onset of symptoms (e.g., in light of a history of symptoms and/or in light of genetic or other susceptibility factors). Treatment is also continued after symptoms have resolved, for example to prevent, delay or lessen the severity of their recurrence.

[00298] In some embodiments, the present invention provides methods of making compounds useful for treating, stabilizing or lessening the severity or progression of one or more diseases or disorders associated with one or both of ERK1 and ERK2.

[00299] General diseases, conditions, or disorders treated by compounds prepared using methods of the present invention include cancer, an autoimmune disorder, a neurodegenerative or neurological disorder, liver disease, a cardiac disorder, schizophrenia, or a bone-related disorder.

[00300] In some embodiments, the present invention provides methods of making compounds useful for treating or lessening the severity of a disease, condition, or disorder selected from cancer, stroke, diabetes, hepatomegaly, cardiovascular disease including cardiomegaly, Alzheimer's disease, cystic fibrosis, viral disease, autoimmune diseases, atherosclerosis, restenosis, psoriasis, allergic disorders including asthma, inflammation, neurological disorders and hormone-related diseases, wherein the method comprises administering to a patient in need thereof a composition comprising a compound of the present invention.

[00301] In some embodiments, the present invention provides methods of making compounds useful for treating a cancer. In some embodiments, the cancer is recurring. In certain embodiments, the cancer is refractory. In some embodiments, the cancer is metastatic. In some embodiments, the cancer is locally advanced.

[00302] In certain embodiments, the cancer is a RAF inhibitor-resistant cancer. In some such embodiments, the RAF inhibitor-resistant cancer is a BRAF inhibitor-resistant cancer.

[00303] In certain embodiments, the cancer is a MEK inhibitor-resistant cancer.

[00304] In certain embodiments, the cancer is a MAPK pathway-mediated cancer.

[00305] In some embodiments, the cancer is a BRAF-mutated cancer. In certain embodiments, the BRAF-mutated cancer is a BRAF^V600-mutated cancer, such as BRAF

BRAF^V600K, BRAF^V600R, and BRAF^V600D.

[00306] In some embodiments, the cancer is a RAS-mutated cancer. In certain embodiments, the RAS-mutated involves codons 12, 13, or 61. In certain embodiments, the RAS-mutated cancer is a KRAS-mutated cancer, including, but not limited to, KRAS^{G12C D V}, KRAS^{G13C D}, or KRAS^{Q61L H R}. In certain embodiments, the RAS-mutated cancer is an RAS-mutated cancer, including, but not limited to, RAS^Q61R, RAS^Q61K, RAS^Q61L, or RAS^Q61H. In certain embodiments, the RAS-mutated cancer is an HRAS-mutated cancer, including, but not limited to, HRAS^G12V, HRAS^Q61R, and HRAS^G12S.

[00307] In some embodiments, the present invention provides methods of making compounds useful for treating a cancer, wherein the cancer is selected from multiple myeloma, breast, ovary, cervix, prostate, testis, genitourinary tract, esophagus, larynx, glioblastoma, neuroblastoma, stomach (gastric), skin, keratoacanthoma, lung, epidermoid carcinoma, large cell carcinoma, small cell carcinoma, lung, bone, colon, thyroid, adenoma, pancreas, adenocarcinoma, thyroid, follicular carcinoma, undifferentiated carcinoma, papillary carcinoma, seminoma, melanoma (including uveal melanoma) sarcoma, bladder carcinoma, liver carcinoma (e.g., hepatocellular carcinoma (HCC)) and biliary passage carcinoma), kidney carcinoma, myeloid disorders, lymphoid disorders, Hodgkin's, hairy cells, buccal cavity and pharynx (oral), lip, tongue, mouth, pharynx, small intestine, colorectal carcinoma, large intestine, rectum, brain and central nervous system, endometrial, multiple myeloma (MM), prostate, AML, and leukemia. In some such embodiments, the cancer is relapsed. In some embodiments, the cancer is refractory. In some embodiments, the cancer is locally advanced. In some embodiments, the cancer is metastatic.

[00308] In some embodiments, the present invention provides methods of making compounds useful for treating a cancer, wherein the cancer is selected from carcinoma, lymphoma, blastoma, sarcoma, and leukemia. In some embodiments, a sarcoma is a soft tissue sarcoma. In some embodiments, a lymphoma is non-hodgkins lymphoma. In some embodiments, a lymphoma is large cell immunoblastic lymphoma. In some embodiments, the cancer is selected from adenocarcinoma; adenoma; adrenocortical cancer; bladder cancer; bone cancer; brain cancer; breast cancer; cancer of the buccal cavity; cervical cancer; colon cancer; colorectal cancer; endometrial or uterine carcinoma; epidermoid carcinoma; esophogeal cancer; eye cancer; follicular carcinoma; gallbladder cancer; prostate, AML, multiple myeloma (MM), gastrointestinal cancer, such as, for example, gastrointestinal stromal tumor; cancer of the genitourinary tract; glioblastoma; hairy cell carcinoma; various types of head and neck cancer; hepatic carcinoma; hepatocellular cancer; Hodgkin's disease; keratoacanthoma; kidney cancer; large cell carcinoma; cancer of the large intestine; laryngeal cancer; liver cancer; lung cancer, such as, for example, adenocarcinoma of the lung, anaplastic carcinoma of the lung, papillary lung adenocarcinoma, small-cell lung cancer, squamous carcinoma of the lung, non-small cell lung cancer; melanoma and nonmelanoma skin cancer; lymphoid disorders; myeloproliferative disorders, such as, for example, polycythemia vera, essential thrombocythemia, chronic idiopathic myelofibrosis, myeloid metaplasia with myelofibrosis, chronic myeloid leukemia (CML), chronic myelomonocytic leukemia, chronic eosinophilic leukemia, chronic lymphocytic leukemia (CLL), hypereosinophilic syndrome, systematic mast cell disease, atypical CML, AML, or juvenile myelomonocytic leukemia; plasmacytoma; multiple myeloma; neuroblastoma; ovarian cancer; papillary carcinoma; pancreatic cancer; cancer of the peritoneum; prostate cancer, including benign prostatic hyperplasia; rectal cancer; salivary gland carcinoma; sarcoma; seminoma; squamous cell cancer; small cell carcinoma; cancer of the small intestine; stomach cancer; testicular cancer; thyroid cancer; undifferentiated carcinoma; and vulval cancer. In some such embodiments, the cancer is relapsed. In some embodiments, the cancer is refractory. In some embodiments, the cancer is locally advanced. In some embodiments, the cancer is metastatic.

[00309] In some embodiments, the present invention provides methods of making compounds useful for treating a cancer, wherein the cancer is selected from melanoma, pancreatic cancer, thyroid cancer, colorectal cancer, lung cancer (e.g., non-small cell lung cancer), breast cancer, endometrial cancer, prostate cancer, ovarian cancer, hepatocellular carcinoma (HCC), multiple myeloma (MM), and leukemia. In some embodiments, a leukemia is an acute leukemia. In certain embodiments, a leukemia is acute myeloid leukemia. In certain embodiments, a leukemia is acute lymphoblastic leukemia.

[00310] In some embodiments, the present invention provides methods of making compounds useful for treating a cancer, wherein the cancer is selected from melanoma, colorectal cancer, lung cancer, or pancreatic.

[00311] In some embodiments, the present invention provides methods of making compounds useful for treating a cancer, wherein the cancer is melanoma. In certain embodiments, the melanoma is uveal melanoma. In some embodiments, the melanoma is a melanoma of the skin. In certain embodiments, the melanoma is locally advanced. In some embodiments, the melanoma is metastatic. In some embodiments, the melanoma is recurring. In some embodiments, the melanoma is BRAF^v600-mutated melanoma. In certain embodiments, the melanoma is a RAS-mutated melanoma. In some embodiments, the melanoma is NRAS- mutated melanoma. In certain embodiments, the melanoma is wild type for KRAS, NRAS or BRAF. In certain embodiments, the melanoma is a BRAF inhibitor-resistant melanoma. In certain embodiments, the cancer is a VemR (i.e., Vemurfenib-resistant) BRAF-mutated melanoma. In some embodiments, the melanoma is relapsed. In some embodiments, the melanoma is refractory.

[00312] In some embodiments, the present invention provides methods of making compounds useful for treating a cancer, wherein the cancer is colorectal cancer. In certain embodiments, the colorectal cancer is locally advanced. In certain embodiments, the colorectal cancer is metastatic. In certain embodiments, the colorectal cancer is a BRAF-mutated colorectal cancer. In certain embodiments, the colorectal cancer is a BRAF^v600-mutated colorectal cancer. In certain embodiments, the colorectal cancer is a RAS-mutated colorectal cancer. In certain embodiments, the colorectal cancer is a KRAS-mutated colorectal cancer. In certain embodiments, the colorectal cancer is a NRAS-mutated colorectal cancer. In some embodiments, the colorectal cancer is relapsed. In some embodiments, the colorectal cancer is refractory.

[00313] In some embodiments, the present invention provides methods of making compounds useful for treating a cancer, wherein the cancer is pancreatic cancer. In certain embodiments, the pancreatic cancer is locally advanced. In certain embodiments, the pancreatic cancer is metastatic. In certain embodiments, the pancreatic cancer is a pancreatic ductal adenocarcinoma (PDAC). In certain embodiments, the pancreatic cancer is a RAS-mutated pancreatic cancer. In certain embodiments, the pancreatic cancer is a KRAS-mutated pancreatic cancer. In certain embodiments, the pancreatic cancer is KRAS-mutated pancreatic cancer, including, but not limited to, KRAS^G12C/D/V, KRAS^G13C/D, or KRAS^Q61L/H/R. In some embodiments, the pancreatic cancer is relapsed. In some embodiments, the pancreatic cancer is refractory.

[00314] In some embodiments, the present invention provides methods of making compounds useful for treating a cancer, wherein the cancer is a papillary thyroid cancer. In certain embodiments, the papillary thyroid cancer is locally advanced. In some embodiments, the papillary thyroid cancer is metastatic. In some embodiments, the papillary thyroid cancer is recurring. In some embodiments, the papillary thyroid cancer is BRAF-mutated papillary thyroid cancer. In some embodiments, the papillary thyroid cancer is BRAF^v600-mutated papillary thyroid cancer. In some embodiments, the papillary thyroid cancer is relapsed. In some embodiments, the papillary thyroid cancer is refractory.

[00315] In some embodiments, the present invention provides methods of making compounds useful for treating a cancer, wherein the cancer is lung cancer. In certain embodiments, the lung cancer is non-small cell lung cancer (NSCLC). In certain embodiments, the lung cancer is locally advanced. In certain embodiments, the lung cancer is metastatic. In certain embodiments, the lung cancer is a RAS-mutated lung cancer. In certain embodiments, the lung cancer is KRAS-mutated lung cancer. In certain embodiments, the lung cancer is a KRAS- mutated lung cancer, including, but not limited to, KRAS^G12C/D/V, KRAS^G13C/D, or KRAS^Q61L/H/R. In some embodiments, the lung cancer is relapsed. In some embodiments, the lung cancer is refractory.

[00316] In some embodiments, the present invention provides methods of making compounds useful for treating a cancer, wherein the cancer is a leukemia. In some embodiments, a leukemia is a chronic leukemia. In certain embodiments, a leukemia is chronic myeloid leukemia. In some embodiments, a leukemia is an acute leukemia. In certain embodiments, a leukemia is acute myeloid leukemia (AML). In certain embodiments, a leukemia is acute monocytic leukemia (AMoL, or AML-M5). In certain embodiments, a leukemia is acute lymphoblastic leukemia (ALL). In certain embodiments, a leukemia is acute T cell leukemia. In certain embodiments, a leukemia is myelomonoblastic leukemia. In certain embodiments, a leukemia is human B cell precursor leukemia. In certain embodiments, a leukemia has a Flt3 mutation or rearrangement. In some embodiments, the leukemia is relapsed. In some embodiments, the leukemia is refractory.

[00317] In some embodiments, the present invention provides methods of making compounds useful for treating a cancer, wherein the cancer is a CNS cancer, for instance CNS tumors. In certain embodiments, a CNS tumor is a glioblastoma or glioblastoma multiforme (GBM). In some embodiments, the present invention relates to a method of treating stomach (gastric) and esophageal tumors and cancers.

[00318] In some embodiments, the present invention provides methods of making compounds useful for treating a cancer, wherein the cancer is multiple myeloma (MM). In certain embodiments, the multiple myeloma is locally advanced. In certain embodiments, the multiple myeloma is metastatic. In certain embodiments, the multiple myeloma is a RAS-mutated multiple myeloma. In certain embodiments, the multiple myeloma is KRAS-mutated multiple myeloma. In certain embodiments, the multiple myeloma is a KRAS-mutated multiple myeloma, including, but not limited to, KRAS^G12C/D/V, KRAS^G13C/D, or KRAS^Q61L/H/R. In some embodiments, the multiple myeloma is relapsed. In some embodiments, the multiple myeloma is refractory.

[00319] In some embodiments, the present invention provides methods of making compounds useful for treating a cancer, wherein the cancer is hepatocellular carcinoma (HCC). In certain embodiments, the HCC is locally advanced. In certain embodiments, the HCC is metastatic. In certain embodiments, the HCC is a RAS-mutated HCC. In certain embodiments, the HCC is KRAS-mutated HCC. In certain embodiments, the HCC is a KRAS-mutated HCC, including, but not limited to, KRAS^G12C/D/V, KRAS^G13C/D, or KRAS^Q61L/H/R. In some embodiments, the hepatocellular carcinoma is relapsed. In some embodiments, the hepatocellular carcinoma is refractory.

[00320] In some embodiments, the present invention provides methods of making compounds useful for treating a cancer, wherein the cancer is selected from breast, colorectal, endometrial, hematological, leukemia (e.g., AML), liver, lung, melanoma, ovarian, pancreatic, prostate, or thyroid.

[00321] All features of each of the aspects of the invention apply to all other aspects mutatis mutandis. Each of the references referred to herein, including but not limited to patents, patent applications and journal articles, is incorporated by reference herein as though fully set forth in its entirety.

[00322] In order that the invention described herein may be more fully understood, the following examples are set forth. It should be understood that these examples are for illustrative purposes only and are not to be construed as limiting this invention in any manner.

EXEMPLIFICATION

[00323] As depicted in the Examples below, in certain exemplary embodiments, compounds are prepared according to the following general procedures. It will be appreciated that, although the general methods depict the synthesis of certain compounds of the present invention, the following general methods, and other methods known to one of ordinary skill in the art, can be applied to all compounds and subclasses and species of each of these compounds, as described herein.

[00324] Proton Nuclear Magnetic Resonance (1H NMR) spectra were obtained on a Bruker AVANCE-300 MHz NMR spectrometer.

Example 1. Synthesis of a Phosphate Salt of Compound I Scheme I Synthetic Route:

CI

[00327] Synthesis of a Compound of Formula E: Compound 7 (Scheme I Synthetic Route)

[00328] Compound 4 (2-Methoxy-5-methylpyridin-4-amine) (100 g, 1.0 equiv), 10 N sodium hydroxide (3.5 ml, 0.05 equiv), and 2-methyltetrahydrofuran (200 ml, 2 volumes) were charged to a reactor and heated to 75 °C to 80 °C. In a separate reactor di-tert-butyl dicarbonate (237 g, 1.5 equiv) was dissolved in 2-methyltetrahydrofuran (100 ml, 1 volume). The solution of di-tert- butyl dicarbonate in 2-methyltetrahydrofuran was charged to the solution of compound 4 over about 12 to 16 hours while maintaining a reaction temperature for 75 °C to 80 °C. The batch was further reacted at this temperature for about 6 hours, followed by a second charge of di-tert-butyl dicarbonate (16 g, 0.1 equiv) dissolved in 2-methyltetrahydrofuran (10 ml, 0.1 volume). The batch was further agitated at 75 °C to 80 °C for 6 hours. An in process control was taken, and if required additional di-tert-butyl dicarbonate was charged in 16 g (0.1 mol) portions until at least 95% conversion was reached.

[00329] The batch was then cooled to 20 to 30 °C, and diluted with water (300 ml, 3 volumes) and 2-methyltetrahydrofuran (200 ml, 2 volumes). The batch was agitated, settled, and the aqueous layer was removed. The product containing organic layer was further washed three times with water (300 ml, 3 volumes, each).

[00330] The batch was reduced to 5 volumes by vacuum distillation (batch temperature 40 °C to 50 ⁰ C) followed by a continuous vacuum distillation with fresh 2-methyltetrahydrofuran at 40 °C to 50 °C until a water content of no more than 0.2% was reached. The batch temperature was adjusted to 55 °C to 65 °C and vacuum distilled at this temperature range while maintaining 5 volumes by the addition of n-heptane until a level of no more than 6% 2-methyltetrahyrofuran with respect to n-heptane was reached. The batch was further reduced to 4.5 volumes, cooled to 40 to 45 °C, seeded with seed crystals of the product compound 7 (i.e., tert-butyl(2-methoxy-5- methylpyridin-4-yl)carbamate), agitated for 1 hour, cooled to -5 °C to 5 °C over 3 hours, and held at this temperature range to 16 hours. The batch was filtered, washed with n-heptane (100 ml, 1 volume, cooled to -5 °C to 5 °C), and dried under reduced pressure at 30 °C to 40 °C to yield 120 g of compound 7 (70% yield).

[00331] 1H MR (DMSO) δ 8.65 (1H, s), 7.82 (1H, s), 7.13 (1H, s), 3.76 (3H, s), 2.09 (3H, s), 1.47 (9H, s); MS: M+l Calc: 239.1, Found: 239.2

[00332] Alternative Synthesis of a Compound of Formula E: Compound 7 (Scheme I Synthetic Route)

[00333] Compound 4 (100 g, 1.0 equiv) and 2-methyltetrahydrofuran (100 ml, 1 volume) were charged to a reactor and heated to 75 °C to 80 °C. In a separate reactor di-tert-butyl dicarbonate (158 g, 1.2 equiv) was dissolved in 2-methyltetrahydrofuran (100 ml, 1 volume). The solution of di-tert-butyl dicarbonate in 2-methyltetrahydrofuran was charged to the solution of compound 4 over about twelve hours while maintaining a reaction temperature of 75 °C to 80 °C, after addition the batch was maintained in this temperature range for a further twelve hours. An in process control was taken, if required additional di-tert-butyl dicarbonate was charged as a solution in 2-methyltetrahydrofuran (-16 g active, 0.1 molar equiv each) until at least 95% conversion was reached.

[00334] The batch was cooled to 20 °C to 30 °C and diluted with 2-methyltetrahydrofuran (200 ml, 2 volumes) and n-heptane (200 ml, 2 volumes). The batch was washed with 1% wt aqueous citric acid solution (300 ml, 3 volumes), water (300 ml, 3 volumes), 1% wt aqueous sodium bicarbonate (300 ml, 3 volumes), and water (300 ml, 3 volumes).

[00335] The batch was distilled at 50 °C to 65 °C under reduced pressure to 550 ml (5.5 volumes), then continuously distilled at 50 °C to 65 °C while maintaining a volume of 550 ml (5.5 volumes) by the addition of n-heptane until 2-methyltetrahydrofuran was less than 5% by mole with respect to n-heptane (about 1200 ml, 12 volumes n-heptane).

[00336] The batch was cooled to 45 °C to 50 °C followed by the addition of compound 7 seed crystals (1 g, 0.0 IX wt). The batch was agitated at 45 °C to 50 °C for one hour, cooled to 0 °C to 10 °C over four hours, agitated at 0 °C to 10 °C for 16 hours, filtered, washed once with n- heptane (100 ml, 1 X vol) cooled to 0 °C to 10 °C, and dried under reduced pressure at 30 °C to 40 °C to yield 120 g compound 7 (70% yield).

[00337] 1H NMR (DMSO) δ 8.65 (1H, s), 7.82 (1H, s), 7.13 (1H, s), 3.76 (3H, s), 2.09 (3H, s), 1.47 (9H, s). MS: M+l Calc: 239.1, Found: 239.2

[00338] Alternative Synthesis of a Compound of Formula E: Compound 7 (Scheme I' Synthetic Route)

[00339] Step 1: Sodium methoxide (142 g, 2629 mmol) and toluene (795 ml) were charged to a reactor, heated to about 90 °C, and distilled under reduced pressure to remove about 2 volumes (210 ml) of toluene. The batch was then cooled, and compound 10 (i.e., 2,4-dichloro-5- methylpyridine) (106 g, 654 mmol) was charged, followed by a toluene rinse (53 ml). The batch was then heated to about 104 °C and reacted for about 36 hours. After reaction completion the batch was cooled to about 25 °C and washed twice with water (424 ml each), once with 10 to 15% aqueous citric acid (424 ml), once with water (424 ml), once with 2% aqueous sodium bicarbonate (424 ml), and once with water (424 ml).

[00340] Step 2: Tert-butylcarbamate (89 g, 760 mmol), cesium carbonate (318 g, 976 mmol), palladium acetate (2.94 g, 13.1 mmol), and Xantphos (4,5-bis(diphenylphosphino)-9,9- dimethylxanthene, 9.09 g, 15.7 mmol) were charged to a fresh reactor and inerted. The batch from step 1, above, in toluene was transferred and heated to about 95 °C for about 16 hours. After reaction completion the batch was cooled to about 25 °C, diatomaceous earth (10.6 g) was charged, and the resulting mixture was agitated for about 30 minutes, followed by filtration. The batch was reduced in volume to about 424 ml via vacuum distillation at about 80 °C.

[00341] The batch was then transferred to a fresh reactor containing activated carbon (42.4 g) and trithiocyanuric acid (42.4 g) followed by addition of n-heptane (2120 ml). The batch was agitated at about 25 °C for at least 8 hours, then filtered. The filter cake was washed twice with 1/5 v/v toluene/n-heptane (106 ml each), and the combined filtrates were charged to fresh activated carbon (42.4 g). The batch was agitated for at least 4 hours at about 25 °C and filtered. The filter cake was then washed once with 1/5 v/v toluene/n-heptane (106 ml).

[00342] The batch was reduced in volume to about 530 ml via vacuum distillation (about 65 °C) and the solvent was exchanged to n-heptane while maintaining this volume and temperature. The batch was then cooled to about 10 °C with intermittent seeding with compound 7, agitated at about 10 °C, filtered, washed once with n-heptane (106 ml), and dried under reduced pressure at about 40 °C to afford about 115.4 g of product (74% molar yield).

[00343] Synthesis of a Compound of Formula C: Compound 8

[00344] Compound 7 (1.20 kg, 1.0 equiv), compound 2 (i.e., 2,4-dichloro-5- trifluoromethylpyrimidine) (1.50 kg, 80.2 wt% in toluene, 1.1 equiv.; note that neat compound 2 can also be used) and tetrahydrofuran (6.0 L, 5X vol) were charged to a 20 liter jacketed reactor with overhead agitation under nitrogen. The batch temperature was cooled to -20 °C to -10 °C. Potassium tert-butyoxide (1.6 to 1.7 M in THF, 2.90 L, 0.95 equiv) was charted over about 1.5 hours, maintaining a batch temperature between -20 °C to -10 °C (targeting -15 °C). The batch was sampled for reaction completion by HPLC, additional potassium tert-butoxide was charged portion-wise while maintaining a temperature between -20 °C to -10 °C until no more than 1% compound 7 remained. Water (3.6 L, 3X vol ) was charged to quench while maintaining a batch temperature of no more than 0 °C. The batch temperature was adjusted to 20 °C to 25 °C, agitated, settled and split. Heptane (3.6 L, 3X vol) and water (3.6 L, 3X vol) were charged, the batch was agitated, settled and split. The batch was washed two more times with water (3.6 L, 3X vol each). The batch was transferred to a separate reactor with activated carbon (600 g, 0.5X wt) for agitation. The batch was agitated between 20 °C to 30 °C for 16 hours and filtered over a pad of diatomaceous earth (180 g, 0.15X wt). The cake was washed twice with THF (1.2 L, IX vol each). The combined filtrates were distilled under reduced pressure to 5X volumes followed by a continuous vacuum distillation with heptane until a composition of no more than 1 % mol tetrahydrofuran and no more than 8 % mol toluene was achieved. The batch was adjusted to 50 °C to 60 °C, compound 8 seeds were charged (12 g) , the batch was agitated at 50 °C to 60 °C for 1 hour, then cooled to 10 °C over 3 hours. The batch was further agitated at 10 °C for 4 hours, filtered, and washed with heptane (1.2 L, IX vol).

[00345] The batch was dried under reduced pressure at 35 °C to 45 °C to yield 1780 g of compound 8 (i.e., tert-butyl(4-chloro-5-(trifluoromethyl)pyrymidin-2-yl)(2-methoxy-5- methylpyridin-4-yl)carbamate) (84% yield).

[00346] 1H NMR (CDC1₃) δ = 8.71 (1 H, s), 8.11 (1 H, s), 6.55 (1 H, s), 3.95 (3 H, s), 2.07 (3 H, s), 1.49 (9 H, s). MS: M+1 Calc: 419.1, 421.1, Found: 419.2, 421.1 [00347] Synthesis of a Compound of Formula A: Compound 9

[00348] Compound 8 (750 g, 1 molar equiv), compound 3 in HC1 salt form (i.e., N-(2-amino- 5-methylphenyl)acrylamide hydrochloride) (419 g, 1.1 molar equiv) and N-methylpyrrolidinone (2.25 L, 3.0 X vol) were charged to a 20 liter jacketed with overhead agitator under nitrogen. The batch was agitated at 20 °C to 30 °C. Diisopropylethylamine (0.78 L, 2.5 equiv) was charged to the batch while maintaining a temperature of 20 to 30 °C. The batch was heated to 65 °C to 70 °C over about 1 hour, reacted at 65 °C to 70 °C for about 20 hrs, then heated to 67 °C to 73 °C for another 4 hours until compound 8 was no more than 2% by HPLC.

[00349] The batch was cooled to 25 °C to 35 °C and isopropyl acetate (11.25 L, 15X vol) was charged. A separately prepared citric acid 5% (wt/vol) aqueous solution (2.25 L, 3X vol) was charged to the batch while maintaining a temperature of 25 °C to 35 °C. The batch was agitated, settled and the aqueous layer (bottom) was removed. The citric acid wash was repeated three more times. A sodium bicarbonate 5% (wt/vol) aqueous solution (2.25 L, 3X vol) was charged to the batch while maintaining a temperature of 25 °C to 35 °C. The batch was agitated, settled and the aqueous layer (bottom) was removed. The batch was finally washed with water (2.25 L, 3X vol) while maintaining a temperature of 25 °C to 35 °C.

[00350] The batch was vacuum distilled to about 7X volumes while maintaining a temperature of 45 °C to 55 °C then adjusted to 12X volumes by the addition of fresh isopropylacetate. The batch was transferred to a fresh vessel with activate carbon (150 g, 0.2 X wt) and agitated at 20 °C to 30 °C for about 4 hrs. The batch was filtered through diatomaceous earth, the filter cake was washed with isopropyl acetate (1.5 L, 2X vol).

[00351] The combined filtrates were distilled under reduced pressure to about 3X volumes while keeping batch between 45 °C to 55 °C. n-Heptane (2.25 L, 3X vol) was charged while maintaining the temperature between 45 °C to 55 °C. Compound 9 seeds (7.5 g, 0.01 X wt) were charged as a suspension in n-heptane. The batch was agitated at 45 °C to 55 °C for 2 hours followed by charging additional n-heptane (6.75 L, 9X vol) over 4 hours. The batch was cooled to 25 °C over 3 hours and aged at this temperature for 3 hours. The batch was filtered and washed with isopropyl acetate : heptane in a 1 : 4 ratio (1.5 L, 2X vol). The batch was dried under vacuum at 45 °C to 55 °C with a nitrogen bleed for 16 hours to yield 848 g of compound 9 (i.e., tert-butyl(4((2-acrylamido-4-methylphenyl(amino)-5-(trifluoromethyl)pyrimidin-2-yl)(2- methoxy-5-methylpyridin-4-yl)carbamate) (83% yield).

[00352] 1H NMR (DMSO) δ = 10.28 (s, 1 H), 8.68 (s, 1 H), 8.50 (s, 1 H), 8.06 (s, 1 H), 7.26 (d, J = 8.3 Hz, 1 H), 7.08 (s, 1 H), 6.89 - 6.81 (m, 1 H), 6.59 (s, 1 H), 6.54 - 6.41 (m, J = 9.8, 16.8 Hz, 1 H), 6.32 (dd, J= 2.1, 17.0 Hz, 1 H), 5.81 (dd, J= 1.9, 9.8 Hz, 1 H), 3.84 (s, 3 H), 2.29 (s, 3 H), 1.92 (s, 3 H), 1.30 (s, 9 H); MS: M+l Calc: 559.2, Found: 558.9.

[00353] Synthesis of Compound I

I

t-Bu Compound I

[00354] A solution of sulfuric acid in methanol was prepared by slowly diluting sulfuric acid (98%, 147 g, 1.2 equiv) in methanol (1.4 L, 2X vol). In a separate reactor compound 9 (700 g, 1.0 equiv) was dissolved in methanol (5.6 L, 8X vol) at 20 °C to 30 °C. The sulfuric acid- methanol solution was charged to the batch while maintaining a temperature of no more than 30 °C. The batch was heated to 35 °C to 45 °C and agitated for 4 hours at which time an in process control sample by HPLC detected no more than 0.2% compound 9. The batch was cooled to 20 °C to 30 °C.

[00355] In a separate vessel triethylamine (354 g, 2.8 equiv) was dissolved in methanol (3.5 L, 5 vol). The triethylamine-methanol solution was charged to the batch over one hour while maintaining a batch temperature between 20 °C and 30 °C during which time Compound I crystallized from solution. The batch was agitated for a further 4 hours at 20 °C to 30 °C, filtered, washed twice with methanol (3.5 L, 5 vol each) and dried under reduced pressure at 30 to 40 °C with a nitrogen bleed to afford 550 g of compound 6 (83% yield).

[00356] 1H NMR (DMSO) δ 10.29 (1H, s), 8.74 (1H, s), 8.40 (1H, s), 8.39 (1H, s), 7.81 (1H, s), 7.53 (1H, d, J= 8.1 Hz), 7.15 - 7.08 (3H, m), 6.46 (1H, dd, J= 16.8, 9.9 Hz), 6.31 (1H, dd, J = 17.1, 2.1 Hz), 5.80 (1H, dd, J= 9.9, 2.1 Hz), 3.77 (3H, s), 2.34 (3H, s), 2.12 (3H, s); MS: M+l Calc: 459.2, Found: 459.2.

[00357] Synthesis of a Phosphate Salt of Compound I

Compound I Compound I

[00358] Compound I (200 g, 1 equiv) and tetrahydrofuran (3.2 L, 16X vol) were charged to the reactor and agitated at 20 °C to 25 °C to dissolve. The batch was atmospherically distilled to 13X volume then continuously distilled with the addition of ethyl acetate (5.1 L) while maintaining a volume of 13X. The batch was cooled to 25 °C to 35 °C.

[00359] Alternatively Compound I was dissolved in 8 volumes of 95:5 tetrahydrofuran: water

(vol: vol) then solvent exchanged to ethyl acetate as above.

[00360] Alternatively Compound I was charged to 12 volumes of ethyl acetate.

[00361] In a separate vessel phosphoric acid (85% wt, 60.4 g, 1.2 equiv) was charged to ethanol (960 ml, 4.8X vol).

[00362] Compound I seeds (4 g, 0.02X by weight) were charged to the batch in ethyl acetate. The phosphoric acid-ethanol solution was charged over 2 hours while maintaining a batch temperature of 25 °C to 35 °C. The batch was further agitated in this temperature range for 12 hours. The batch was filtered, dried, washed twice with ethyl acetate (400 ml, 2X vol each), and dried under reduced pressure to yield 224 g of Compound I as the phosphate salt (90%).

[00363] 1H NMR (DMSO) δ 10.29 (1H, s), 8.75 (1H, s), 8.38 (1H, s), 8.38 (1H, s), 7.80 (1H, s), 7.52 (1H, d, J= 9.0 Hz), 7.12 (1H, s), 7.10 (1H, s), 7.09 (1H, d, J= 6.9 Hz), 6.45 (1H, dd, J = 16.8, 9.6 Hz), 6.30 (1H, dd, J = 16.8, 2.1 Hz), 5.79 (1H, dd, J = 9.9, 2.1 Hz), 3.77 (3H, s), 2.33 (3H, s), 2.11 (3H, s); MS: M+l Calc: 459.2, Found: 459.5. Preparation of Form A of a Phosphate Salt of Compound I

I

Form A of a Phosphate Salt of Compound I

[00364] In instances in which Form A of Compound I was used to seed the above-described salt formation reaction, Form A of Compound I was prepared using any one of the following procedures.

[00365] Procedure A: Compound I was dissolved in 15X tetrahydrofuran. One molar equivalent of 2 molar phosphoric acid in acetonitrile was charged. The batch was slurried at 20 °C for 1 to 2 hours. The solvent was removed under reduced pressure. The resulting solids were slurried in acetone for about 16 hours at 20 °C, filtered and dried.

[00366] Procedure B: Compound I was dissolved in THF. Equal molar equivalent of 1.08 M phosphoric acid in acetonitrile was charged. The sample was shaken at ambient temperature at 200 RPM for 1 hour. The solvent was removed under nitrogen purge. The resulting solids were slurried in acetone with a stirring bar at ambient temperature overnight, then filtered and dried in vacuum oven at 30 °C overnight.

[00367] Procedure C: Compound I was dissolved in THF (20X vol) at 20° C. Seeds of Form A of the phosphate salt of Compound I (5% wt) were charged. A I M solution of phosphoric acid (1 mol eq.) in ethanol was charged. The batch was left under vigorous agitation for two hours. Solvent exchange to isopropyl acetate was carried out with a constant volume distillation under reduced pressure, with temperature not exceeding 40° C. The batch was cooled to 20° C. The solvent was removed under nitrogen purge. The batch was filtered, washed two times with isopropyl acetate and dried in a vacuum oven at -40 ° C overnight, under vacuum with nitrogen bleed. [00368] Procedure D: Compound I was dissolved in 9X vol THF/ H₂0 (95:5 vol). A solution of H₃PO₄ (1.2 mol eq.) in ethanol was charged to a second flask, seeds of Form A of the phosphate salt of Compound I (5%) were charged and vigorous agitation was started. The solution of Compound I was charged to the H₃PO₄ solution (reverse addition) over one hour. The slurry was aged for one hour. Solvent exchange to ethanol was started (constant volume vacuum distillation with continuous addition of ethanol, final THF NMT 0.5%). The batch was cooled to 20° C, filtered and dried in a vacuum oven at -40 ⁰ C overnight, under vacuum with nitrogen bleed.

[00369] Procedure E: Compound I was dissolved in 10X vol THF/H₂0 (95:5 vol). Isopropyl alcohol (5X vol) was charged. Constant volume distillation, with continuous addition of isopropyl alcohol was started at atmospheric pressure. Solvent exchange was carried out until THF content was below 5%. Compound I recrystallized during the solvent exchange. The batch was cooled to 30 °C. A I M solution of H₃PO₄ in IPA was charged over 2 hours. Seeds of Form A of the phosphate salt of Compound I (1%) were then charged. The batch was stirred vigorously overnight. The batch was filtered and dried in a vacuum oven at -40 °C overnight, under vacuum with nitrogen bleed.

[00370] Procedure F: Compound I was dissolved in 9X vol THF/H₂0 (95:5 vol). After polish filtration, distillation to reduce volume from 9X to 5X was performed, followed by addition of 8X ethyl acetate to bring the total volume to 13X. Solvent exchange to ethyl acetate, with constant volume distillation was carried out (final THF NMT 2%). The temperature was then reduced to 30 °C. Seeds of a phosphate salt of Compound I (1% wt) were charged. A solution of H₃PO₄ (1.2 eq.) in ethanol (5X) was then dosed in over 2 hours. The temperature was reduced to 20 °C, the batch was aged for 12 hours under vigorous stirring, then filtered, washed two times with ethyl acetate and dried in a vacuum oven at -40 °C overnight, under vacuum with nitrogen bleed.

[00371] Procedure G: Compound I was charged to a reactor, then ethanol (4X vol) and ethyl acetate (6X), were charged. The batch was agitated at 30° C. A solution of H₃PO₄ (1.2 mol eq.) in ethanol (2X vol) was charged over 2 hours. Seeds of Form A of the phosphate salt of Compound I (1%) were charged. The batch was filtered, washed two times with ethyl acetate, dried overnight at -40° C, under vacuum with nitrogen bleed. [00372] Characterization of the resulting material demonstrated a crystalline, anhydrous Form A of the phosphate salt of Compound I. Up to 0.9% water uptake was observed for this Form at 95% relative humidity.

[00373] Table 5, supra, is reproduced below and sets forth the X-ray diffraction peaks observed for Form A of the phosphate salt of Compound I.

Table 5 - XRPD Peak Positions for Form A of a Phosphate Salt of Compound I

In this and al subsequent tables,

the position 2 Θ is within ± 0.2.

[00374] Figure 9 depicts an XRPD pattern of Form A of the phosphate salt of Compound I.

[00375] Figure 10 depicts a DSC thermogram of Form A of the phosphate salt of Compound I

[00376] Figure 11 depicts a TGA trace of Form A of the phosphate salt of Compound I.

[00377] Figure 12 depicts a DVS plot of Form A of the phosphate salt of Compound I.

[00378] Elemental analysis - Calculated: C 47.49; H 4.35; N 15.10; P 5.57; Found: C 47.09; H 4.33; N 14.90; P 5.57.

[00379] Karl Fisher titration: 0.22% [00380] Alternative Methods of Preparing Form A of a Phosphate Salt of Compound I

[00381] In some embodiments, the present invention provides a crystallization procedure that generates crystals having certain physical properties that facilitate product processing. One such exemplary method is described below.

Compound I Compound I

[00382] A 20% (0.2X weight) portion of the total final mass of Compound I (i.e., 20% of the total amount of free base Compound I by weight) was charged to a reactor. A mixture of ethyl acetate/ethanol 13:5 vol (13X vol) was charged. Agitation was started and the temperature was raised to 30 °C and held at that temperature for 30 minutes. A solution of phosphoric acid (1.2 molar equiv.) was prepared in 5X ethyl acetate/ethanol (13:5 vol). A portion (20% of the 1.2 molar equiv) of the phosphoric acid solution was charged to the reactor over about 20 minutes. Seeds (2% by wt) of the phosphate salt of Compound I (Form A) were charged and the batch was aged for 30 minutes.

[00383] Ten heat-cool cycles were carried out between 20 °C and 40 °C (at a heating rate of 0.5 °C /minute, cooling rate 0.1 °C/minute - the start was by heating from 30 °C to 40 °C, the end was by heating from 20 °C to 30 °C in last cycle). Specifically, during the first eight cycles the starting temperature was 30 °C, heated to 40 °C at a rate of 0.5 °C/minute (i.e., 20 minutes total of heating), then cooled back to 30 °C at a rate of 0.1 °C/minute (i.e., 100 minutes total of cooling). For the ninth cycle, the temperature was lowered to 20 °C at 0.1 °C/minute. For the tenth and last cycle, the initial temperature of 20 °C was raised to 30 °C at a rate of 0.5 °C/minute, and was then cooled to 20 °C at a rate of 0.1 °C/minute.

[00384] The remaining 80% of Compound I solids (0.8X wt) were then charged to the reactor. The remaining 80% of the phosphoric acid solution was charged over at least 1.5 hours maintaining a batch temperature at or below 30 °C. The batch was agitated for 12 hours at 30 °C, then cooled to 23 °C, filtered, washed twice (with 2X vol ethyl acetate), dried under reduced pressure (40 °C to 50 °C with nitrogen bleed) and de-lumped. Figure 13 shows PLM images of the product crystals at different stages of the above-described process.

[00385] In an alternative process, 100% free base Compound I was charged to the reactor, seeded with 2% of the phosphate salt of Compound I (Form A), charged with a portion (20%) of the H₃PO₄ solution and then subjected to subsequent heat-cool cycles (as described above). The remaining 80% of the H₃PO₄ solution was then charged over 1.5 hours, followed by cooling to 23 °C, filtration, wash, drying and delumping. This alternative procedure achieved similar physical properties of the product while giving an opportunity to dissolve the product in TFIF/H₂O, carry out polish filtration and then carry out a solvent exchange to ethyl acetate/ethanol. Figure 14 depicts such a procedure and depicts PLM images at different stages of the process.

[00386] Synthesis of Compound 11

[00387] Compound B-4 (4-methyl-2-nitroaniline, 210 g, 1 equiv) and formic acid (735 ml, 3.5 volumes) were heated at 50 °C for at least 5 hours. The reaction was cooled to 15 °C to 20 °C then charged to water (735 ml, 3.5 volumes) over about 1 hour while maintaining a batch temperature of about 15 °C to 20 °C. The resulting slurry was agitated for a further 2 hours at 15 °C, filtered, washed with 1 : 1 formic acid: water (210 ml, 1 volume), then three times with water (315 ml, 1.5 volumes each), and dried under reduced pressure at 45 °C to yield 225 g compound 11 (i.e., N-(4-methyl-2-nitrophenyl)formamide) (90%).

[00388] 1H NMR (DMSO) δ 10.46 (0.9H, s), 9.95 (0.1H, s), 8.62 (0.1H, s), 8.35 (0.9H, s), 7.94 (1H, d, J = 7.8 Hz), 7.87 (1H, s), 7.54 (1H, dd, J = 8.1, 1.2 Hz), 2.36 (3H, s); MS: M+l Calc: 181.1, Found: 181.1

[00389] Synthesis of Compound 13

[00390] Compound 11 (25.0 g), 10% palladium on carbon (1.25 g, 0.05X by weight, 50% water wet), tetrahydrofuran (325 ml, 13 volumes), and water (50 ml, 2 volumes) were agitated under 5 to 20 psi of hydrogen at a temperature of no more than 50 °C until the resulting exotherm had subsided. The hydrogen pressure was the increased to 30 to 40 psi for 3 hours while maintaining a temperature of 50 °C to complete conversion to compound 12 (i.e., N-(2-amino-4- methylphenylformamide)). The batch was exchanged to a nitrogen atmosphere, cooled to 20 °C to 30 °C, filtered through Celite 503 (2.5 g, 0.1X weight), followed by two cake washes (25 ml, 1 volume, of 13:2 THF:water each).

[00391] The resulting solution of compound 12 in tetrahydrofuran/ water was charged to a solution of potassium carbonate (19.2 g, 0.77X weight) in water (100 ml, 4 volumes) and cooled to 0 °C to 10 °C. Acryloyl chloride (11.8 ml, 0.47 volumes, 1.05 molar equiv) was charged over 30 minutes while maintaining a batch temperature below 10 °C. After addition the batch was held at 5 °C to 10 °C for 30 minutes, warmed to 25 °C, and further diluted with tetrahydrofuran (50 ml, 2 volumes). The batch was settled and the lower, aqueous layer was removed. The batch was then reduced in volume to 150 ml (6 volumes) by vacuum distillation while maintaining a batch temperature of 30 °C to 40 °C. Water (250 ml, 10 volumes) was then charged to the batch at about 35 °C, during which time compound 13 crystallizes. The resulting slurry was cooled to 25 °C, agitated for three hours and filtered. The wet cake was washed with tetrahydrofuran:water (1 :2, 38 ml, 1.5 volumes) and dried under reduced pressure at 30 °C to 40 °C to yield 20.3 compound 13 (i.e., N-(2-formamido-5-methylphenyl)acrylamide) (72% yield from compound

11)

[00392] 1H MR (DMSO) δ 9.73 (0.3H, s), 9.56 (0.7H, s), 9.48 (0.7H, s), 9.31 (0.3H, d, J = 10.8 Hz), 8.36 (0.3H, d, J= 11.1 Hz), 8.25 (0.7H, d, J= 1.8 Hz), 7.66 (0.7 H, d, J= 8.4 Hz), 7.41 (0.3H, s), 7.35 (0.7H, s), 7.21 (0.3H, d, J = 8.1 Hz), 7.02 - 6.98 (1H, m), 6.55 - 6.43 (1H, m), 6.30 - 6.21 (1H, m), 5.80 - 5.74 (1H, m), 2.28 (1H, s), 2.27 (2H, s). MS: M+l Calc: 205.1, Found: 205.1

[00393] Synthesis of Compound B HCI Salt

[00394] Compound 13 (20.0 g) was slurried in methanol (100 ml, 5 volumes) and methyl tert- butyl ether (200 ml, 10 volumes). Hydrochloric acid (36%, 19.8 ml, 0.99 vol) was charged over about 30 minutes while maintaining a batch temperature for 15 °C to 25 °C. The batch was heated to 20 °C to 25 °C and agitated for five hours. Additional methyl tert butyl ether (40 ml, 2 volumes) was charged, the batch was agitated for an additional one hour, filtered, and washed with methanol: methyl tert butyl ether (1 :2.4, 50 ml, 2.5 volumes), and dried under reduced pressure to afford 17.5 g of compound B (i.e., N-(2-amino-5-methylphenyl)acrylamide hydrochloride) (84% yield).

[00395] 1H MR (DMSO) δ 10.58 (1H, s), -10-9 (3H, br), 7.36 (1H, s), 7.30 (1H, d, J = 8.1 Hz), 7.11 (1H, dd, J = 8.1, 1.2 Hz), 6.56 (1H, dd, J= 17.1, 10.2 Hz), 6.32 (1H, dd, J = 17.1, 2.1 Hz), 5.84 (1H, dd, J = 10.2, 1.8 Hz), 2.31 (3H, s). MS: M+l Calc: 177.1 (free base), Found: 177.1

Claims

We claim:

1. A method for preparing Compound I:

Compound I

or a pharmaceutically acceptable salt thereof, comprising steps of:

(a) providing compound F:

wherein PG¹ is a suitable amine protecting group;

(c) coupling a compound of formula E to a compound of formula D:

wherein each of LG¹ and LG² is independently a suitable leaving group,

under suitable conditions to provide a compound of formula C:

(d) coupling a compound of formula C to compound B:

under suitable conditions to form a compound of formula A:

(e) deprotecting a compound of formula A under suitable conditions to provide

Compound I or a pharmaceutically acceptable salt thereof.

2. The method of claim 1, wherein PG¹ is BOC.

3. The method of claim 1, wherein LG¹ is chloro.

4. The method of claim 1, wherein LG² is chloro.

5. The method of claim 1, wherein compound B is provided as the HC1 salt.

6. The method of claim 1, wherein a compound of formula D is of the following structure:

7. The method of claim 1, wherein a compound of formula C is of the following structure:

8. The method of claim 1, further comprising a step of reacting Compound I with a suitable acid to provide a pharmaceutically acceptable salt of Compound I:

wherein HX is any suitable acid comprising at least one hydrogen The method of claim 8, wherein a suitable acid is phosphoric acid. A method for preparing compound B:

or a salt thereof, comprising steps of:

(a) providing compound B-4:

wherein PG³ is a suitable amine protecting group;

11. The method of claim 10, wherein PG is formyl.

12. The method of claim 10, wherein compound B is prepared as the HC1 salt.

13. A method for preparing compound B:

or a salt thereof, comprising steps of:

(a) providing compound B-12:

(b) reacting the free amine of compound B-12 under suitable conditions in the presence of 3-chloropropionyl choride to provide compound B-5:

(c) reducing compound B-5 under suitable conditions to provide compound B-6:

14. The method of claim 13, wherein compound B is prepared as the HC1 salt.

15. A method for preparing compound B:

or a salt thereof, comprising steps of:

(a) providing compound B-12:

(c) exposing compound B-7 to methanol under suitable conditions to provide compound B-8:

(d) reducing compound B-8 under suitable conditions to provide compound B-9:

16. The method of claim 15, wherein compound B is prepared as the HC1 salt.

17. A method for preparing compound B:

or a salt thereof, comprising steps of:

(a) providing compound B-10:

18. The method of claim 17, wherein compound B is prepared as the HC1 salt.

19. A method for preparing compound B:

or a salt thereof, comprising steps of:

(a) providing a compound of formula B-ll:

wherein LG is a suitable leaving group; and

(b) coupling a compound of formula B-ll under suitable conditions in the presence of acrylamide to provide compound B or a salt thereof.

20. The method of claim 19, wherein compound B is prepared as the HC1 salt.

21. The method of claim 19, wherein LG³ is selected from chloro, iodo, bromo, fluoro, sulfoxide, sulphone, methanesulfonyloxy, tosyloxy, triflyloxy, benzenesulfonyloxy, nitro- phenylsulfonyloxy, and bromo-phenylsulfonyloxy.

22. A composition comprising Compound I:

armaceutically acceptable salt thereof, and at least one compound selected from:

or a pharmaceutically acceptable salt thereof. 23. Compound 7:

wherein said compound is of Form A.

24. The compound according to claim 23, having one or more peaks in its XRPD selected from those at about 16.7, 19.6, and 19.9 degrees 2-theta.

25. The compound according to claim 23, having at least two peaks in its XRPD selected from those at about 16.7, 19.6, and 19.9 degrees 2-theta.

26. The compound according to claim 23, having an XRPD substantially similar to that depicted in Figure 1.

27. Compound 8:

wherein said compound is of Form A.

28. The compound according to claim 27, having one or more peaks in its XRPD selected from those at about 9.3, 19.6 and 20.0 degrees 2-theta.

29. The compound according to claim 27, having at least two peaks in its XRPD selected from those at about 9.3, 19.6 and 20.0 degrees 2-theta.

30. The compound according to claim 27, having an XRPD substantially similar to that depicted in Figure 3.

31. Compound 9:

wherein said compound is of Form A.

32. The compound according to claim 31, having one or more peaks in its XRPD selected from those at about 5.8, 8.4, and 11.5 degrees 2-theta.

33. The compound according to claim 31, having at least two peaks in its XRPD selected from those at about 5.8, 8.4, and 11.5 degrees 2-theta.

34. The compound according to claim 31, having an XRPD substantially similar to that depicted in Figure 5.

35. Compound 9:

wherein said compound is of Form B.

36. The compound according to claim 35, having one or more peaks in its XRPD selected from those at about 7.0, 14.1, and 21.2 degrees 2-theta.

37. The compound according to claim 35, having at least two peaks in its XRPD selected from those at about 7.0, 14.1, and 21.2 degrees 2-theta.

38. The compound according to claim 35, having an XRPD substantially similar to that depicted in Figure 7.

39. A method for preparing a phosphate salt of Compound I, comprising steps of:

(a) providing a first portion of free base Compound I:

(d) performing one or more heat-cool cycles on the mixture;