WO1998057964A1

WO1998057964A1 - Tricyclic compounds useful for inhibition of g-protein function and for treatment of proliferative diseases

Info

Publication number: WO1998057964A1
Application number: PCT/US1998/011506
Authority: WO
Inventors: Joseph M. Kelly; Adriano Afonso
Original assignee: Schering Corporation
Priority date: 1997-06-17
Filing date: 1998-06-15
Publication date: 1998-12-23
Also published as: AU8253498A

Abstract

Disclosed are novel compounds of Formula (I), wherein W is H or halo; X is H, halo, CH3, isopropyl, t-butyl, cyclopropyl, (a) or (b); Y and Z are independently selected from the group consisting of halo, CH3, OCH3, CF3, OCF3 and CH2OH; R is R'-(CH2)nC(O)-, R'-(CH2)nSO2- or R'-OC(O)-, wherein n is 0 to 2; and R' is aryl, heteroaryl or heterocycloalkyl. Also disclosed is a method of inhibiting Ras function and therefore inhibiting the abnormal growth of cells. The method comprises administering a compound of Formula (I) to a biological system. In particular, the method inhibits the abnormal growth of cells in a mammal such as a human being.

Description

TRICYCLIC COMPOUNDS USEFUL FOR INHIBITION OF G-PROTEIN FUNCTION AND FOR TREATMENT OF

PROLIFERATIVE DISEASES

BACKGROUND

WO 95/10516, published April 20, 1995 discloses tricyclic compounds useful for inhibiting farnesyl protein transferase. WO 96/30362, published October 3, 1996, discloses 1 ,2,3,6-tetrahydropyridyl tricyclic derivatives useful for inhibiting farnesyl protein transferase. In view of the current interest in inhibitors of farnesyl protein transferase, a welcome contribution to the art would be compounds useful for the inhibition of farnesyl protein transferase. Such a contribution is provided by this invention.

SUMMARY OF THE INVENTION

This invention provides compounds useful for the inhibition of farnesyl protein transferase (FPT). The compounds of this invention are represented by the formula:

or an N-oxide thereof, or a pharmaceutically acceptable salt or solvate thereof, wherein:

W is H or halo; r CμH₃^ ?|_^H_ X is H, halo, CH3, isopropyl, t-butyl, cyclopropyl, CH_{3 0}r

OH HaC-^- ; Y and Z are independently selected from the group consisting of halo, CH₃, OCH₃, CF₃, OCF3 and CH₂OH;

R is R'-(CH2)_nC(0)-, R'-(CH₂)_nS02- or R'-OC(O)-, wherein n is 0 to 2; and

R' is aryl, heteroaryl or heterocycloalkyl.

Representative compounds of the invention are shown in the following formulas:

Preferred are compounds of formula I wherein X is Br, W and Y are independently halo and Z is H; or X is Br, W is H, and Y and Z are independently halo; or X is Br, Y is halo and W and Z are each H. Y is preferably Br or Cl; when W and Z are halo, they are preferably Cl or Br. Especially preferred are compounds of formula I wherein X, Y and Z are each Br.

Compounds of formula IA are preferred, i.e., compounds wherein R is R'-(CH2)nC(0)-. R' is preferably heteroaryl, more preferably pyridyl or pyridyl N-oxide. The variable n is preferably 1. An example of a preferred compound of formula IA is the following:

In addition to N-oxides at the R' variable, N-oxides of the pyridyl ring of the tricyclic portion are part of this invention

The compounds of this invention: (i) potently inhibit farnesyl protein transferase, but not geranylgeranyl protein transferase I, in vitro: (ii) block the phenotypic change induced by a form of transforming Ras which is a farnesyl acceptor but not by a form of transforming Ras engineered to be a geranylgeranyl acceptor; (iii) block intracellular processing of Ras which is a farnesyl acceptor but not of Ras engineered to be a geranylgeranyl acceptor; and (iv) block abnormal cell growth in culture induced by transforming Ras.

The compounds of this invention inhibit farnesyl protein transferase and the famesylation of the oncogene protein Ras. Thus, this invention further provides a method of inhibiting farnesyl protein transferase, (e.g., ras farnesyl protein transferase) in mammals, especially humans, by the administration of an effective amount of the tricyclic compounds described above. The administration of the compounds of this invention to patients, to inhibit farnesyl protein transferase, is useful in the treatment of the cancers described below. This invention provides a method for inhibiting or treating the abnormal growth of cells, including transformed cells, by administering an effective amount of a compound of this invention. Abnormal growth of cells refers to cell growth independent of normal regulatory mechanisms (e.g., loss of contact inhibition). This includes the abnormal growth of: (1) tumor cells (tumors) expressing an activated Ras oncogene; (2) tumor cells in which the Ras protein is activated as a result of oncogenic mutation in another gene; and (3) benign and malignant cells of other proliferative diseases in which aberrant Ras activation occurs.

This invention also provides a method for inhibiting or treating tumor growth by administering an effective amount of the tricyclic compounds, described herein, to a mammal (e.g., a human) in need of such treatment. In particular, this invention provides a method for inhibiting or treating the growth of tumors expressing an activated Ras oncogene by the administration of an effective amount of the above described compounds. Examples of tumors which may be inhibited or treated include, but are not limited to, breast cancer, prostate cancer, lung cancer (e.g., lung adenocarcinoma), pancreatic cancers (e.g., pancreatic carcinoma such as, for example, exocrine pancreatic carcinoma), colon cancers (e.g., colorectal carcinomas, such as, for example, colon adenocarcinoma and colon adenoma), myeloid leukemias (for example, acute myelogenous leukemia (AML)), thyroid follicular cancer, myelodysplastic syndrome (MDS), bladder carcinoma and epidermal carcinoma. It is believed that this invention also provides a method for inhibiting or treating proliferative diseases, both benign and malignant, wherein Ras proteins are aberrantly activated as a result of oncogenic mutation in other genes-i.e., the Ras gene itself is not activated by mutation to an oncogenic form-with said inhibition or treatment being accomplished by the administration of an effective amount of the tricyclic compounds described herein, to a mammal (e.g., a human) in need of such treatment. For example, the benign proliferative disorder neurofibromatosis, or tumors in which Ras is activated due to mutation or overexpression of tyrosine kinase oncogenes (e.g., neu, src, abl, lck, and fyn), may be inhibited or treated by the tricyclic compounds described herein.

The tricyclic compounds useful in the methods of this invention inhibit or treat the abnormal growth of cells. Without wishing to be bound by theory, it is believed that these compounds may function through the inhibition of G-protein function, such as ras p21 , by blocking G-protein isoprenylation, thus making them useful in the treatment of proliferative diseases such as tumor growth and cancer. Without wishing to be bound by theory, it is believed that these compounds inhibit ras farnesyl protein transferase, and thus show antiproliferative activity against ras transformed cells.

DETAILED DESCRIPTION OF THE INVENTION

As used herein, the following terms are used as defined below unless otherwise indicated: M⁺-represents the molecular ion of the molecule in the mass spectrum;

MH+-represents the molecular ion plus hydrogen of the molecule in the mass spectrum;

Bu represents butyl; Et represents ethyl; Me represents methyl; and Ph represents phenyl; alkyl (including alkyl portions of alkoxy, alkylamino and dialkyl- amino) represents straight and branched carbon chains and contains from one to twenty carbon atoms, preferably one to six carbon atoms; heterocycloalkyl represents a saturated, branched or unbranched carbocylic ring containing from 3 to 15 carbon atoms, preferably from 4 to 6 carbon atoms, which carbocyclic ring is interrupted by 1 to 3 hetero groups selected from -0-, -S- or -NR¹⁰-, wherein R¹⁰ is H, alkyl, aryl, or aralkyl (e.g., benzyl); suitable heterocycloalkyl groups include 2- or 3- tetrahydrofuranyl, 2- or 3- tetrahydrothienyl, 2-, 3- or 4-piperidinyl, 2- or 3- pyrrolidinyl, 2- or 3-piperizinyl, 2- or 4-dioxanyl, etc.; aryl represents a carbocyclic group containing from 6 to 15 carbon atoms and having at least one aromatic ring (e.g., aryl is a phenyl ring), with all available substitutable carbon atoms of the carbocyclic group being intended as possible points of attachment, said carbocyclic group being optionally substituted (e.g., 1 to 3) with one or more of halo, alkyl, hydroxy, alkoxy, phenoxy, CF3, amino, alkylamino, dialkylamino, -COOR¹⁰, wherein R¹⁰ is as defined above, or -NO2; halo represents fluoro, chloro, bromo and iodo; and heteroaryl represents cyclic groups, optionally substituted as defined above for aryl, having at least one heteroatom selected from O, S or N, said heteroatom interrupting a carbocyclic ring structure and having a sufficient number of delocalized pi electrons to provide aromatic character, with the aromatic heterocyclic groups preferably containing from 2 to 14 carbon atoms, e.g., triazolyl, 2-, 3- or 4-pyridyl or pyridyl N- oxide , wherein pyridyl N-oxide can be represented as:

The following solvents and reagents may be referred to herein by the abbreviations indicated: tetrahydrofuran (THF); ethanol (EtOH); methanol (MeOH); acetic acid (HOAc or AcOH); ethyl acetate (EtOAc); N,N-dimethylformamide (DMF); trifluoroacetic acid (TFA); trifluoroacetic anhydride (TFAA); 1-hydroxybenzotriazole (HOBT); m-chloroperbenzoic acid (MCPBA); triethylamine (Et₃N); diethyl ether (Et₂0); ethyl chloroformate (CICO2E-); 1-(3-dimethylaminopropyl)-3-ethyl carbodiimde hydrochloride (DEC).

Certain compounds of the invention may exist in different isomeric (e.g., enantiomers and diastereoisomers) forms. The invention contemplates all such isomers both in pure form and in admixture, including racemic mixtures. Enol forms are also included.

Certain tricyclic compounds will be acidic in nature, e.g. those compounds which possess a carboxyl or phenolic hydroxyl group. These compounds may form pharmaceutically acceptable salts. Examples of such salts may include sodium, potassium, calcium, aluminum, gold and silver salts. Also contemplated are salts formed with pharmaceutically acceptable amines such as ammonia, alkyl amines, hydroxyalkylamines, N-methylglucamine and the like.

Certain basic tricyclic compounds also form pharmaceutically acceptable salts, e.g., acid addition salts. For example, the pyrido- nitrogen atoms may form salts with strong acid, while compounds having basic substituents such as amino groups also form salts with weaker acids. Examples of suitable acids for salt formation are hydrochloric, sulfuric, phosphoric, acetic, citric, oxalic, malonic, salicylic, malic, fumaric, succinic, ascorbic, maleic, methanesulfonic and other mineral and carboxylic acids well known to those in the art. The salts are prepared by contacting the free base form with a sufficient amount of the desired acid to produce a salt in the conventional manner. The free base forms may be regenerated by treating the salt with a suitable dilute aqueous base solution such as dilute aqueous NaOH, potassium carbonate, ammonia and sodium bicarbonate. The free base forms differ from their respective salt forms somewhat in certain physical properties, such as solubility in polar solvents, but the acid and base salts are otherwise equivalent to their respective free base forms for purposes of the invention.

All such acid and base salts are intended to be pharmaceutically acceptable salts within the scope of the invention and all acid and base salts are considered equivalent to the free forms of the corresponding compounds for purposes of the invention.

Compounds and starting materials of the invention may be made by the processes known in the art, for example by processes described in WO 95/10516 (see, for example, the procedures for making compounds of formula 400.00) and WO 96/30362 (see, for example, the procedures for making compounds of formula 7.0b) cited above. In addition, compounds of formula I wherein R is R'-(CH2)n-S02- can be prepared by processes described in WO 95/10514, published April 20, 1995, and compounds wherein R is R'-OC(O)- can be prepared by processes described in WO 95/10515, published April 20, 1995.

For example, compounds of the formula IA wherein R is R'-(CH2)nC(0)- can be prepared from amines of the formula II (6,11- dihydro-11 -(1 ,2,3,6-tetrahydro-1 -methyl-4-pyridinyl)-5H-benzo[5,6]- cyclohepta[1 ,2-b]pyridines) by coupling a compound of the formula II with a carboxylic acid of the formula R'-(CH2)nCOOH via the method described in WO 95/10516 for reacting compounds of the formula 405.00.

Alternatively, a compound of the formula II is treated with a compound of the formula R'-(CH2)nC(0)L, where L is a suitable leaving group, via the procedure described in WO 95/10516 for compounds of the formula 405.00.

Compounds of the formula IB wherein R is R'-(CH2)nS02- can be prepared as described in WO 95/10514 by treating a compound of formula II with a compound such as R'-S02CI in the presence of an organic base such as pyridine or EtβN, or an inorganic base such as sodium carbonate. In place of a sulfonyl chloride, a sulfonyl halide or a sulfonic anhydride (R'-Sθ2θSθ2R') can be used. Compounds wherein R' is heteroaryl or heterocycloalkyl such as pyridyl or piperidyl can be prepared by converting the alcohol, R'OH, to the mesylate, ROSO2CH3. The mesylate can be converted to the thiol, R'SH, by reacting the mesylate with NaSH. The thiol can be oxidized to the sulfonic acid, R'SOaH and the sulfonic acid can be converted to the sulfonyl chloride, R'S02CI, by reacting the sulfonic acid with PCI5.

Compounds of formula IC wherein R is R'-OC(O)- can be prepared as described in WO 95/10515 by treating a compound of formula II with a chloroformate of the formula R'COL, wherein L is Br or Cl, in the presence of a base such as pyridine or Et3N. Compounds of formula IC wherein R' is alkyl can be converted into compounds of formula IA by methods described below.

Compounds of formula IA wherein R' is an N-oxide can be prepared, for example, by coupling compounds of formula II with 4-pyridyl N-oxide acetic acid as described below in Example 1. Compounds of formula IB and IC wherein R' is an N-oxide can be prepared, for example, by treating a corresponding pyridyl compound with a peracid such as MCPBA. Compounds of formula I comprising a pyridyl N-oxide in the tricyclic portion of the molecule can be prepared by procedures well known in the art. For example, the compound of formula II can be reacted with MCPBA in a suitable organic solvent, e.g., CH2CI2 (usually anhydrous), at a suitable temperature, to obtain an N-oxide of formula lla

Generally, the organic solvent solution of formula II is cooled to about 0°C before the MCPBA is added. The reaction is then allowed to warm to room temperature during the reaction period. The desired product can be recovered by standard separation means, for example, the reaction mixture can be washed with an aqueous solution of a suitable base, e.g., saturated NaHC03 or NaOH (e.g., i N NaOH), and then dried over anhydrous MgSθ4. The solution containing the product can be concentrated in vacuo, and the product can be purified by standard means, e.g., by chromatography using silica gel (e.g., flash column chromatography).

If a compound of formula I comprising pyridyl groups in the tricyclic ring and in the pendant ring is treated with MCPBA as described above, di-N-oxides will be prepared.

Compounds of the formula II can be prepared from a compound of formula ill (i.e., a compound of the formula 420.00, of WO 95/10516, wherein A and B are both H, no double bond is present between carbons 5 and 6, a double bond is present between carbon 11 and X, X is C, and the N-alkyl group is a methyl group) via the process shown in the following Reaction Scheme.

In Step A of the Reaction Scheme, a compound of the formula III is reacted with a strong base, such as lithium diisopropylamide or an alkyllithium reagent (e.g., n-butyllithium), at -100° to -10°C, preferably at -80° to -20°C, then treated with a protic solvent, such as an alcohol, preferably MeOH, to form a compound of formula Ilia.

In Step B of the Reaction Scheme, a compound of the formula Ilia is converted to a compound of the formula 11 lb via substantially the same procedure as described in WO 95/10516 for formation of compounds of the formula 415.00.

In Step C of the Reaction Scheme, a compound of the formula 1Mb is hydrolyzed via essentially the same procedure as described WO 95/10516, for formation of compounds of formula 405.00, to form a compound of the formula II.

A similar procedure for preparing the intermediates of formula II is described in Preparative Example 4 of WO 96/30362.

Intermediates of formula Ilia can also be prepared by the procedure described below:

The tricyclic ketone of formula IV is reacted with an N-methyl- piperidyl magnesium halide to obtain the 6,11-dihydro-11-(1 -methyl-4- piperidinyl)-5H-benzo[5,6]cyclhepta[1 ,2-b]pyridin-11-ol of formula V, which is then dehydrated with a reagent such as CF3SO3H to obtain the compounds of formula Ilia and III which are separated by chromatography.

Methods for preparing the tricyclic ketones of formula IV are known in the art: tricyclic ketones are disclosed in WO 95/10516, and in

PCT/US96/19603, filed December 19, 1996. Another process for preparing the tricyclic ketone starting material is described in the example below. In addition, the tricyclic ketone can be prepared by the following process for preparing a compound of the structure

wherein R¹, R², R³, R⁴ and R^{1 1} are independently selected from the group consisting of hydrogen and halo; comprising:

(a) reacting a compound of the formula

(i) with an amine of the formula NHR⁵R⁶, wherein R⁵ is hydrogen and R⁶ is

alkyl, aryl or heteroaryl; R⁵ is

alkyl, aryl or heteroaryl and R⁶ is hydrogen; R⁵ and R⁶ are independently selected from the group consisting of C-i-Cβ alkyl and aryl; or R⁵ and R⁶, together with the nitrogen to which they are attached, form a ring comprising 4 to 6 carbon atoms or comprising 3 to 5 carbon atoms and one hetero moiety selected from the group consisting of -O- and -NR⁹-, wherein R⁹ is H, C-|- Cβ alkyl or phenyl; in the presence of a palladium catalyst and carbon monoxide to obtain an amide of the formula:

(ii) with an alcohol of the formula R¹⁰OH, wherein R¹⁰ is C-|- Cβ lower alkyl or C3-C6 cycloalkyl, in the presence of a palladium catalyst and carbon monoxide to obtain the ester of theformula

followed by reacting the ester with an amine of formula NHR⁵R⁶ to obtain the amide;

(b) reacting the amide with an iodo-substituted benzyl compound of the formula

wherein R¹ , R², R³ and R⁴ are as defined above and R⁷ is Cl or Br, in the presence of a strong base to obtain a compound of formula 4

(c) cyclizing a compound of step (b) with a reagent of the formula R⁸MgL, wherein R⁸ is C-i-Cs alkyl, aryl or heteroaryl and L is Br or Cl, provided that prior to cyclization, compounds wherein R⁵ or R⁶ is hydrogen are reacted with a suitable N-protecting group. Alternatively, compounds of formula III wherein the C-3 postion of the pyridine ring in the structure is substituted by bromo, can be prepared by reacting the amide described above in the process for preparing the tricyclic ketone, wherein R¹¹ is bromo, as follows:

(a) reacting the amide with a compound of the formula

wherein R¹, R², R³ and R⁴ are as defined above and R⁷ is Cl or Br, in the presence of a strong base to obtain a compound of the formula

(b) reacting a compound of step (a) with POCI3 to obtain a cyano compound of the formula

(c) reacting compound of step (b) with a pipehdine derivative of the formula

wherein L is a leaving group selected from the group consisting of Cl and Br, to obtain an aldehyde of the formula:

(d) cyclizing a compound of step (c) with CF3SO3H to obtain a compound of formula III. (+)-lsomers of compounds of formula II can be prepared by using a process comprising enzyme catalyzed transesterification. A racemic compound of formula II, wherein Z is not H, is treated with an enzyme such as Toyobo LIP-300 and acylating agent such as trifluoroethyl isobutyrate; the resultant (+)-amide is then hydrolyzed, for example by refluxing with an acid such as H2SO4, to obtain the corresponding optically enriched (+)-isomer.

On page 57 at lines 7-16 of WO 95/10516, a process is disclosed for introducing substituents at the C-3 position of the pyridine ring of the tricyclic moiety in a compound of formula I by nitrating a compound of Formula 415.00 The nitro group may then be reduced to the corresponding amine using the disclosed reagents, or powdered Zn and either CUCI2 or CuBr2 in aqueous EtOH.

Compounds useful in this invention are exemplified by the following preparative example, which should not be construed to limit the scope of the disclosure. Alternative mechanistic pathways and analogous structures within the scope of the invention may be apparent to those skilled in the art.

Example 1

4-(3,8,10-Tribromo-6,11-Dihydro-5H-Benzo[5,6]Cyclohepta[1 ,2-b]Pyridin-

1 1-yl)-1 ,2,3,6-Tetrahydro-1 -(4-Pyridinylacetyl)Pyridine,N1-Oxide Step 1 :

n-Butyllithium (2.5 M in hexanes, 16.25 ml, 40.61 mmol) was added to a solution of diisopropylamine (5.6 ml, 42.68 mmol) at -78°C, stirred at -78°C for 30 min. and at 0°C for 15 min. The solution was cooled to -78°C and a solution of the t-butyl amide 1 in THF (20 ml) was added dropwise. The resultant purple solution was stirred at -78°C for 30 min., then a solution of 3,5 dibromobenzyl bromide in THF (20 ml) was added dropwise. The reaction was stirred for 3 hr at -78°C and allowed to warm to 0°C. The light brown solution was stirred at 0°C for an additional 30 min., when TLC analysis indicated reaction completion. Water (200 ml) and ether (400 ml) were added, and the organic layer was separated, dried over MgS04, filtered , and the solvent was evaporated yielding a residue which was chromatographed on silica gel, eluting with 5% v/v EtOAc/hexanes to yield product 2 as a white solid (8.34 g, 87.3%). 1 H NMR (CDCI₃) δ 8.43 (s, 1 H), 7.85 (brs, 1 H), 7.60 (s, 1 H), 7.50 (s, 1 H), 7.30 (s, 2H), 3.38 (t, 2H), 2.89 (t, 2H), 1.48 (s, 9H). MS Cl (517, MH). Step 2:

Phosphorous oxychloride (15 ml) was added to a solution of the t- butylamide 2 (8.2 g, 15.8 mmol) in toluene (15 ml) at room temperature, then the solution was refluxed for 4 hrs. The reaction was cooled and the solvent was evaporated. Water (200 ml) was added and the mixture was basified with 10% NaOH, then extracted with CH2CI2 (500 ml). The organic layer was separated, dried over MgS04, filtered and the solvent was evaporated, yielding a solid which on trituration with ether-hexanes yielded product 3 as a white solid (5.5 g, 96.5%).

1HNMR (CDCI3) 68.65 (s, 1 H), 7.75 (s, 1 H), 7.56 (s, 1 H), 7.27 (s, 1 H), 7.26 (s, 1 H), 3.08 (m, 2H), 2.92 (m, 2H). MS (Cl) (443, M+H). Step 3:

METHOD A

A solution of the nitrile 3 (200 mg, 0.548 mmol) in trifluoromethane sulfonic acid (5 ml) was stirred at 80°C for 5 hr, then cooled, poured into ice (50 g) and basified with 25% NaOH. The precipitated solid was filtered, washed with water (10 ml) and dried at room temperature in vacuo, yielding product 4 as a white solid (200 mg, 100%). METHOD B

AICI_3ι 175°C

AICI3 (5.5 g, 41.2 mmol) was added to the nitrile 3 (2.5 g, 6.85 mmol) with stirring at 175°C, and the mixture was stirred at 175°C for 10 min. The reaction was cooled and ice (ca 30 g) was added slowly. Water (100 ml) was added and the mixture was basified with 2N NaOH, then extracted with CH2CI2 (2x200 ml). The organic layers were combined, dried over MgS04 and the solvent was evaporated, yielding a residue which was chromatographed on silica gel, eluting with 70:30 v:v EtOAc:hexanes as a white solid (2.2 g, 40%).

¹H NMR (CDCI3) 6 8.64 (s, 1 H), 7.73 (s, 1 H), 7.64 (s, 1 H), 7.36 (s, 1 H), 3.11 (brs, 4H). MS Cl (443, M+H). Step 4:

4 5

A solution of tricyclic imine 4 (4.44 g, 10 mmol) in cone. H2SO4 (10 ml) was stirred at 160°C for 2 days. The reaction was cooled and the solution poured into ice (100 g), basified with 2N NaOH, then extracted with CH2CI2 (2x200 ml). The organic layer was separated, dried over MgSθ4, filtered and the solvent was evaporated, yielding a white solid (2.9 g, 66%).

1H NMR (CDCI3) 68.75 (s, 1 H), 7.60 (s, 1 H), 7.56 (s, 1 H), 7.21 (s,1 H), 3,21 (t, 2H), 3.13 (t, 2H). MS Cl (444, MH). Exact Mass (FAB) Measured: 443.8234; Calc MH (Cι₄H₉NOBr₃): 443.8234. Step 5:

An 0.8 M solution of 1-methyl-4-piperidyl magnesium chloride (10 ml, 8 mmol) was added dropwise to a solution of the tricyclic ketone 5 (1.65 g, 3.70 mmol) in THF (50 ml, anhydrous) at 0°C, then stirred for I hour at 0°C. The reaction mixture was poured into ice (50 g), saturated NH4CI solution (10 ml) was added, and the mixture was extracted with CH2CI2 (2x100 ml). The organics were combined, dried over MgSθ4, filtered, and the solvent was evaporated, yielding a residue which was chromatographed on silica gel, eluting with 10% v/v CH3OH: CH2CI2 containing 2% NH4OH, yielding product 6 as a yellow solid (1.6 g, 80%). ¹H NMR (CDCI3) 68.43 (s, 1 H), 7.74 (s, 1 H), 7.62 (s, 1 H), 7.20 (s, 1 H), 6.85 (s, 1 H), 3.60 (m,1 H), 3.40 (m, 1 H), 2.6-3.1 (m, 5H), 2.23 (s, 3H), 1.85 (m, 2H). MS Cl (543, M+H).

Step 6:

CF₃SO3H, 60^ϋC

A solution of 6 (3,8,10-tribromo-6,11-dihydro-11-(1-methyl-4- piperidinyl)-5H-benzo[5,6]cyclhepta[1 ,2-b]pyridin-11-ol) (2.3 g, 4.22 mmol) in trifluoromethanesulfonic acid (40 ml) was stirred at 60°C for 3 hours, then cooled and poured into ice (200 g). The mixture was basified with 20% NaOH, extracted with CH2CI2 (200 ml), dried over MgS04, filtered, and the solvent evaporated, yielding a solid which was chromatographed on silica gel, yielding product 7 as a yellow solid (0.9 g, 40.9%). ¹ H NMR 6 8.48 (s, 1 H), 7.64 (s, 1 H), 7.54 (s, 1 H), 7.23 (s, 1 H), 5.66 (s, 1 H), 4.83 (s, 1 H), 3.70 (m, 1 H), 3.25 (m, 1 H), 2.85 (m, 2H), 2.65 (m, 1 H), 2.55 (m, 1 H), 2.40 (m, 1 H), 2.30 (s, 3H), 1.90 (s, 2H). MS Cl (525, M+H). CICOOC₂HP

Ethyl chloroformate (3 ml) was added to a solution of 7 (3,8,10- tribromo-6, 11 -dihydro-11 -(1 ,2,3, 6-tetrahydro-1 -methyl-4-pyridinyl)-5H- benzo[5,6]cyclohepta[1 ,2-b]pyridine (0.8 g, 1.51 mmol) in toluene:1 ,2- dichloroethane 1 :1 v/v (10 ml) at room temperature, then refluxed for 4 hr. The reaction was cooled to room temperature and the solvent was evaporated. Water (40 mi) and 10% NaOH (10 ml) were added, and the mixture was extracted with CH2CI2 (100 ml), washed with water (40 ml), dried over MgS04, filtered, and the solvent was evaporated, yielding product 9 as an oil (0.8 g), MS Cl (M+H, 583), which was used without further purification in the next step.

Step 8:

A solution of 9 (0.4 g, 0.683 mmol) in cone. HCI (5 ml) was stirred at 100°C overnight, then cooled to room temperature. The reaction mixture was poured into ice (50 g), basified with 20% NaOH, then extracted with CH2CI2 (2x100 ml), dried over MgSθ4, filtered, and the solvent evaporated, yielding a white solid (0.25 g, 71%). 1H NMR (CDCI3) δ 8.48 (s, 1 H), 7.65 (s, 1 H), 7.56 (s, 1 H), 7.26 (s, 1 H), 5.67 (s, 1 H), 4.90 (s, 1H), 3.72 (m, 1H), 3.31 (m, 2H), 3.23 (m, 1H), 2.90 (m, 3H), 2.69 (m, 1 H), 1.80 (brs, 2H). MS Cl (511 , M+H). Exact Mass (FAB): Measured: 510.9011 ; Calculated MH (Cι₉H₁₈NBr): 510.9020.

DEC (70 mg, 0.365 mmol), HOBT monohydrate (50 mg, 0.37 mmol) and 4-methylmorpholine (0.1 ml, 0.9 mmol) were added to a solution of 10 (3,8,10-tribromo-6,11 -dihydro-11 -(1 ,2,3,6-tetrahydro-4-pyridinyl)-5H- benzo[5,6]-cyclohepta[1 ,2-b]pyridine) (70 mg, 0.136 mmol) and 4-pyridyl- N-oxide acetic acid (70 mg, 0.457 mmol) in DMF (anhydrous, 3 ml) at 0°C, then stirred overnight at room temperature. The solvent was evaporated, water (20 ml) was added and the mixture was extracted with CH2CI2 (2x50 ml). The organic layer was washed with 10% Na2Cθ3, dried over MgSθ4, filtered, and the solvent evaporated, yielding an oil. The oil was chromatographed on silica gel, eluting with 10% v/v CH3OH-CH2CI2 to yield the product 11 as a white solid (60 mg, 68%). NMR (CDCI3) 68.50 (s, 1 H), 8.14 (d, 1 H), 7.67 (s, 1 H), 7.58 s, 1 H), 7.26 (s, 1 H), 5.70 (d, 2H), 4.90 (s, 1 H), 3.95 (m, 2H), 3.75 (m, 1 H), 3.63 (s, 2H), 3.55 (m, 4H), 3.20 (m, 1 H), 2.85 (m, 1 H), 2.65 (m, 1 H), 1.95 (brs, 2H). MS (FAB) Measured: 645.9319; Calculated MH C26H23N₃θ2Br₃: 645.9340.

ASSAYS

FPT IC50 (inhibition of farnesyl protein transferase in vitro enzyme assay), GGPT IC50 (inhibition of geranylgeranyl protein transferase in vitro enzyme assay), COS Cell IC50 (Cell-Based Assay) and Cell Mat Assay are determined by the assay procedures described in WO 95/10516. The preferred compound of the invention exhibits an FPT IC50 of 3.7 nm.

For preparing pharmaceutical compositions from the compounds described by this invention, inert, pharmaceutically acceptable carriers can be either solid or liquid. Solid form preparations include powders, tablets, dispersible granules, capsules, cachets and suppositories. The powders and tablets may be comprised of from about 5 to about 70 percent active ingredient. Suitable solid carriers are known in the art, e.g. magnesium carbonate, magnesium stearate, talc, sugar, lactose. Tablets, powders, cachets and capsules can be used as solid dosage forms suitable for oral administration.

For preparing suppositories, a low melting wax such as a mixture of fatty acid glycerides or cocoa butter is first melted, and the active ingredient is dispersed homogeneously therein as by stirring. The molten homogeneous mixture is then poured into convenient sized molds, allowed to cool and thereby solidify.

Liquid form preparations include solutions, suspensions and emulsions. As an example may be mentioned water or water-propylene glycol solutions for parenteral injection.

Liquid form preparations may also include solutions for intranasal administration.

Aerosol preparations suitable for inhalation may include solutions and solids in powder form, which may be in combination with a pharmaceutically acceptable carrier, such as an inert compressed gas.

Also included are solid form preparations which are intended to be converted, shortly before use, to liquid form preparations for either oral or parenteral administration. Such liquid forms include solutions, suspensions and emulsions.

The compounds of the invention may also be deliverable transdermally. The transdermal compositions can take the form of creams, lotions, aerosols and/or emulsions and can be included in a transdermal patch of the matrix or reservoir type as are conventional in the art for this purpose.

Preferably the compound is administered orally. Preferably, the pharmaceutical preparation is in unit dosage form. In such form, the preparation is subdivided into unit doses containing appropriate quantities of the active component, e.g., an effective amount to achieve the desired purpose.

The quantity of active compound in a unit dose of preparation may be varied or adjusted from about 0.1 mg to 1000 mg, more preferably from about 1 mg. to 300 mg, according to the particular application.

The actual dosage employed may be varied depending upon the requirements of the patient and the severity of the condition being treated. Determination of the proper dosage for a particular situation is within the skill of the art. Generally, treatment is initiated with smaller dosages which are less than the optimum dose of the compound. Thereafter, the dosage is increased by small increments until the optimum effect under the circumstances is reached. For convenience, the total daily dosage may be divided and administered in portions during the day if desired.

The amount and frequency of administration of the compounds of the invention and the pharmaceutically acceptable salts thereof will be regulated according to the judgment of the attending clinician considering such factors as age, condition and size of the patient as well as severity of the symptoms being treated. A typical recommended dosage regimen is oral administration of from 10 mg to 2000 mg/day preferably 10 to 1000 mg/day, in two to four divided doses to block tumor growth. The compounds are non-toxic when administered within this dosage range.

The following are examples of pharmaceutical dosage forms which contain a compound of the invention. The scope of the invention in its pharmaceutical composition aspect is not to be limited by the examples provided.

Pharmaceutical Dosage Form Examples EXAMPLE A Tablets

Method of Manufacture

Mix Item Nos. 1 and 2 in a suitable mixer for 10-15 minutes. Granulate the mixture with Item No. 3. Mill the damp granules through a coarse screen (e.g., 1/4", 0.63 cm) if necessary. Dry the damp granules. Screen the dried granules if necessary and mix with Item No. 4 and mix for 10-15 minutes. Add Item No. 5 and mix for 1-3 minutes. Compress the mixture to appropriate size and weigh on a suitable tablet machine. EXAMPLE B Capsules

Method of Manufacture

Mix Item Nos. 1 , 2 and 3 in a suitable blender for 10-15 minutes. Add Item No. 4 and mix for 1-3 minutes. Fill the mixture into suitable two- piece hard gelatin capsules on a suitable encapsulating machine.

While the present invention has been described in conjunction with the specific embodiments set forth above, many alternatives, modifications and variations thereof will be apparent to those of ordinary skill in the art. All such alternatives, modifications and variations are intended to fall within the spirit and scope of the present invention.

Claims

WHAT IS CLAIMED IS:

1. A compound represented by the structural formula

W is H or halo;

X is H, halo, CH3, isopropyl, t-butyl, cyclopropyl,

_or OH

H₃C^ ; Y and Z are independently selected from the group consisting of halo, CH₃, OCH3, CF₃, OCF3 and CH₂OH;

R is R'-(CH2)nC(0)-, R'-(CH₂)_nS02- or R'-OC(O)-, wherein n is 0 to 2; and

R' is aryl, heteroaryl or heterocycloalkyl.

2. A compound of claim 1 wherein X is Br and Y and Z are independently selected from the group consisting of Br and Cl.

3. A compound of claim 1 or 2 wherein R is R'-(CH2)nC(0)-.

4. A compound of claim 3 wherein n is 1.

5. A compound of claim 3 or 4 wherein R' is pyridyl or pyridyl N-oxide.

6. A compound of claim 5 wherein X, Y and Z are each Br.

7. A compound of claim 5 wherein X is Br, Z is Br and Y is Cl.

8.

9. The use of a compound of any of claims 1 , 2, 3, 4, 5, 6, 7 or 8 for the preparation of a medicament for inhibiting the abnormal growth of cells.

10. A pharmaceutical composition for inhibiting the abnormal growth of cells comprising an effective amount of compound of claim 1 in combination with a pharmaceutically acceptable carrier.