WO2013036994A1 - Composés pour le traitement des infections par vhc - Google Patents

Composés pour le traitement des infections par vhc Download PDF

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Publication number
WO2013036994A1
WO2013036994A1 PCT/AU2012/001091 AU2012001091W WO2013036994A1 WO 2013036994 A1 WO2013036994 A1 WO 2013036994A1 AU 2012001091 W AU2012001091 W AU 2012001091W WO 2013036994 A1 WO2013036994 A1 WO 2013036994A1
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Prior art keywords
cyclohexyl
imidazo
methyl
optionally substituted
amino
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PCT/AU2012/001091
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English (en)
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Barbara Frey
Richard Hufton
Michael Harding
Alistair George Draffan
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Biota Scientific Management Pty Ltd
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Publication of WO2013036994A1 publication Critical patent/WO2013036994A1/fr

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    • C—CHEMISTRY; METALLURGY
    • C07—ORGANIC CHEMISTRY
    • C07D—HETEROCYCLIC COMPOUNDS
    • C07D487/00—Heterocyclic compounds containing nitrogen atoms as the only ring hetero atoms in the condensed system, not provided for by groups C07D451/00 - C07D477/00
    • C07D487/02—Heterocyclic compounds containing nitrogen atoms as the only ring hetero atoms in the condensed system, not provided for by groups C07D451/00 - C07D477/00 in which the condensed system contains two hetero rings
    • C07D487/04—Ortho-condensed systems
    • A—HUMAN NECESSITIES
    • A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
    • A61K—PREPARATIONS FOR MEDICAL, DENTAL OR TOILETRY PURPOSES
    • A61K31/00—Medicinal preparations containing organic active ingredients
    • A61K31/33—Heterocyclic compounds
    • A61K31/395—Heterocyclic compounds having nitrogen as a ring hetero atom, e.g. guanethidine or rifamycins
    • A61K31/41—Heterocyclic compounds having nitrogen as a ring hetero atom, e.g. guanethidine or rifamycins having five-membered rings with two or more ring hetero atoms, at least one of which being nitrogen, e.g. tetrazole
    • A61K31/4164—1,3-Diazoles
    • A61K31/4188—1,3-Diazoles condensed with other heterocyclic ring systems, e.g. biotin, sorbinil
    • A—HUMAN NECESSITIES
    • A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
    • A61K—PREPARATIONS FOR MEDICAL, DENTAL OR TOILETRY PURPOSES
    • A61K31/00—Medicinal preparations containing organic active ingredients
    • A61K31/33—Heterocyclic compounds
    • A61K31/395—Heterocyclic compounds having nitrogen as a ring hetero atom, e.g. guanethidine or rifamycins
    • A61K31/55—Heterocyclic compounds having nitrogen as a ring hetero atom, e.g. guanethidine or rifamycins having seven-membered rings, e.g. azelastine, pentylenetetrazole
    • A61K31/553—Heterocyclic compounds having nitrogen as a ring hetero atom, e.g. guanethidine or rifamycins having seven-membered rings, e.g. azelastine, pentylenetetrazole having at least one nitrogen and one oxygen as ring hetero atoms, e.g. loxapine, staurosporine
    • A—HUMAN NECESSITIES
    • A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
    • A61K—PREPARATIONS FOR MEDICAL, DENTAL OR TOILETRY PURPOSES
    • A61K45/00—Medicinal preparations containing active ingredients not provided for in groups A61K31/00 - A61K41/00
    • A61K45/06—Mixtures of active ingredients without chemical characterisation, e.g. antiphlogistics and cardiaca
    • A—HUMAN NECESSITIES
    • A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
    • A61P—SPECIFIC THERAPEUTIC ACTIVITY OF CHEMICAL COMPOUNDS OR MEDICINAL PREPARATIONS
    • A61P31/00—Antiinfectives, i.e. antibiotics, antiseptics, chemotherapeutics
    • A61P31/12—Antivirals
    • A61P31/14—Antivirals for RNA viruses
    • C—CHEMISTRY; METALLURGY
    • C07—ORGANIC CHEMISTRY
    • C07D—HETEROCYCLIC COMPOUNDS
    • C07D498/00—Heterocyclic compounds containing in the condensed system at least one hetero ring having nitrogen and oxygen atoms as the only ring hetero atoms
    • C07D498/12—Heterocyclic compounds containing in the condensed system at least one hetero ring having nitrogen and oxygen atoms as the only ring hetero atoms in which the condensed system contains three hetero rings
    • C07D498/14—Ortho-condensed systems

Definitions

  • the present invention relates to viral polymerase inhibitors, in particular inhibitors of viral polymerases within the Flaviviridae family such as hepatitis C virus (HCV), processes for their preparation and their use in the treatment of Flaviviridae viral infections such as Hepatitis C virus (HCV) infections.
  • HCV hepatitis C virus
  • the Flaviviridae are a group of positive single-stranded RNA viruses with a genome size from 9-15 kb.
  • the Flaviviridae consist of various genera including: Hepaciviruses (this genus contains only one species, the Hepatitis C virus (HCV), which is composed of many genotypes and subtypes); Flaviviruses (this genus includes the Dengue virus, Japanese Tick-Borne and the Yellow Fever virus and there are some additional Flaviviruses that are unclassified) and Pestiviruses (this genus includes three serotypes of bovine viral diarrhoea virus, but no known human pathogens).
  • HCV Hepatitis C virus
  • Hepatitis C virus is a major cause of viral hepatitis and has infected more than 200 million people worldwide.
  • Hepatitis C virus has a positive-strand RNA genome enclosed in a nucleocapsid and lipid envelope.
  • the HCV genome is approximately 9.6 kb in length and encodes a polyprotein of about 3,000 amino acids.
  • genotypes 1 a and 1 b account for about 75 % of cases, and genotypes 2 and 3 for 10-20 % of cases. Significant differences are observed in the geographic distribution of HCV genotypes. For example, in Europe genotypes 2 and 3 comprise up to one half of cases whereas genotype 3 is thought to dominate in India.
  • varied genotype are observed in the geographic distribution of HCV genotypes.
  • HCV chronic bloodborne infection
  • HCV pegylated interferon
  • SVR sustained viral response
  • patients with HCV genotype 1 remain the most difficult to treat, with SVR rates of approximately 40% after 48 weeks of therapy.
  • combination peg-IFN/ribavirin therapy is limited by serious side effects, including fatigue, influenza-like symptoms, depression and suicide with peg-I FN, and haemolytic anaemia with ribavirin.
  • peg-IFN/ribavirin therapy is contra-indicated in patients who have depression, anaemia, HCV-related decompensated cirrhosis, alcohol/substance abuse and autoimmune disorders or who are pregnant.
  • telaprevir Very short-acting antiviral
  • boceprevir boceprevir
  • Both drugs are protease inhibitors and are approved for the treatment of chronic HCV genotype 1 infection in combination with peg-IFN and ribavirin.
  • Pivotal phase 3 trials demonstrated that the addition of telaprevir or boceprevir to peg-IFN/RBV therapy achieved shortened durations of therapy and potent viral suppression, with SVR rates approaching 75% in genotype 1 treatment-naive patients and 30% to 85% in treatment-experienced patients.
  • telaprevir is associated with an increased incidence of rash and anaemia
  • boceprevir is associated with anaemia and dysgeusia.
  • Triple therapy with telaprevir or boceprevir and peg-IFN/ribavirin remains unsuitable for those intolerant to or with contraindications to peg-I FN/ribavirin therapy.
  • the HCV genome possesses structural (core) and non-structural (NS2, NS3, NS4A, NS4B, NS5A and NS5B) proteins.
  • the non-structural proteins are involved in viral genomic replication, with the initial synthesis of RNA carried out by NS5B RNA dependent RNA polymerase.
  • the NS5B protein is a key target for anti-HCV therapy, as it is essential for HCV replication and has no human host equivalent. This protein has been well characterised and is a validated target for drug discovery.
  • HCV therapy is also anticipated to evolve towards oral multidrug therapy, in which combinations of different DAA drugs with complementary mechanisms of action serve to increase viral suppression and delay or prevent the emergence of resistance.
  • HCV agents particularly with targeted mechanisms of action such as NS5B inhibitors.
  • HCV agents with cross-genotypic activity against genotypes 1 , 2 and 3.
  • the inventors have found a new class of antiviral compounds, more particularly NS5B polymerase inhibitors, for the treatment of HCV infections.
  • Compounds of the present invention are therefore considered to be useful in treating and preventing hepatitis C infections when used on their own or in combination with one or more other antiviral agents such as ribavirin, an antiviral nucleoside, polymerase inhibitor, protease inhibitor and/or inhibitor of viral entry, assembly or egress.
  • the combination may also additionally comprise at least one immunomodulatory agent for example an interferon or interferon derivative and/or an inhibitor of inosine-5'-monophosphate dehydrogenase (IMPDH).
  • IMPDH inosine-5'-monophosphate dehydrogenase
  • compounds of the invention will be efficacious in combination with at least one other DAA with a different mechanism of action and a complementary resistance profile (for example an NS5A inhibitor, a nucleoside or nucleotide NS5B inhibitor or a NS3/4A protease inhibitor) thereby offering an alternative treatment regime for patients not eligible for or treatable with the recently approved triple combination therapy.
  • a complementary resistance profile for example an NS5A inhibitor, a nucleoside or nucleotide NS5B inhibitor or a NS3/4A protease inhibitor
  • R 1 is H or R a or R 1 together with R 2 and the atoms to which they are attached form an optionally substituted 6-8 membered carbocyclic ring which may be optionally interrupted by one or more heteroatoms independently selected from O, N and S;
  • R 2 is H or R b or R 2 together with Ri joins to form an optionally substituted 6-8 membered carbocyclic ring which may be optionally interrupted by one or more heteroatoms independently selected from O, N and S;
  • R 3 is an optionally substituted C 3 - 8 cycloalkyl group
  • Xi, X 2 and X 3 are each independently selected from N, CH, C-R c and C-A-R 4 provided that at least one of Xi , X 2 and X 3 is C-A-R 4 ;
  • A is a covalent bond, -CONH-C(R 5 )(R 6 )-B- or -CONCi-aalkyl-CiRsXReJ-B-;
  • R 4 is selected from H, C0 2 H, optionally substituted C0 2 Ci_ 6 alkyl, optionally substituted aryl, optionally substituted arylCi_ 6 alkyl, optionally substituted arylC 2 . 6 alkenyl, optionally substituted heterocyclyl, optionally substituted heteroaryl, optionally substituted heterocyclylC ⁇ alkyl, optionally substituted heteroarylC ⁇ alkyl, optionally substituted heterocyclylC 2 - 6 alkenyl and optionally substituted heteroarylC 2 - 6 alkenyl;
  • R 5 and R 6 are each independently selected from H, optionally substituted C ⁇ alkyl, optionally substituted aryl, optionally substituted C ⁇ alkylaryl, optionally substituted heterocyclyl, optionally substituted heteroaryl, optionally substituted C 1 . 6 alkylheterocyclyl and optionally substituted C ⁇ alkylheteroaryl or R 5 and R 6 together with the carbon atom to which they are attached form an optionally substituted C 3 . 6 cycloalkyl group;
  • B is a covalent bond or -CONH-R7- where R 7 is selected from optionally substituted aryl, optionally substituted arylCi -6 alkyl, optionally substituted arylC 2 . 6 alkenyl, optionally substituted heterocyclyl, optionally substituted heteroaryl, optionally substituted
  • heterocyclylC ⁇ alkyl optionally substituted heteroarylC ⁇ alkyl, optionally substituted heterocyclylC 2 - 6 alkenyl and optionally substituted heteroarylC 2 - 6 alkenyl;
  • Z 1 is C or N
  • Z 2 , Z 3 , Z 4 and Z 5 are each independently selected from N, CH and C-R d ;
  • each R 8 is independently selected from H and C 1 . 6 alkyl and each alkyl, alkenyl, alkynyl, cycloalkyi, aryl, heterocyclyl and heteroaryl in the definition of R a , R b , R c and R d may be optionally substituted;
  • each heterocyclyl or heteroaryl has 1 , 2, 3 or 4 heteroatoms independently selected from O, S and N.
  • C-A-R 4 is not C-H.
  • ⁇ , X' 2 and X' 3 are each independently selected from N, CH, C-R c , C-A-R' 4 provided that at least one of ⁇ , X' 2 and X' 3 is C-A-R' 4 wherein R' 4 is C0 2 H or COaC ⁇ alkyl; and
  • Ri, R2, R3, R5, R6, R7, C-R c , Zi, Z 2 , Z 3 , Z 4 and Z 5 are as defined above.
  • the compounds of formula (I) are inhibitors of HCV.
  • the compounds of formula (I) inhibit RNA synthesis by the RNA dependent RNA polymerase of HCV (the NS5B protein encoded by HCV).
  • NS5B polymerase inhibitors have been clinically validated as potential antiviral agents for the treatment of HCV infection.
  • a pharmaceutical agent comprising the compound of formula (I) defined above and pharmaceutically acceptable salts, N-oxides, solvates, hydrates, racemates, enantiomers and isomers thereof.
  • the pharmaceutical agent may be an antiviral agent.
  • a viral polymerase inhibitor in particular a HCV polymerase inhibitor such as a NS5B polymerase inhibitor comprising the compound of formula (I) defined above and pharmaceutically acceptable salts, N-oxides, solvates, hydrates, racemates, enantiomers and isomers thereof.
  • the compound of formula (I ) and pharmaceutically acceptable salts, N-oxides, solvates, hydrates, racemates, enantiomers and isomers thereof may be administered in the form of a pharmaceutical composition together with a pharmaceutically acceptable carrier.
  • a pharmaceutical composition comprising the compound of formula (I) and pharmaceutically acceptable salts, N-oxides, solvates, hydrates, racemates, enantiomers and isomers thereof and a pharmaceutically acceptable carrier.
  • the pharmaceutical composition additionally comprises a therapeutically effective amount of one or more antiviral agents such as at least one other anti-HCV agent.
  • a method for the treatment of a Flaviviridae viral infection such as a HCV infection which comprises administering an effective amount of the compound of formula (I) and pharmaceutically acceptable salts, W-oxides, solvates, hydrates, racemates, enantiomers and isomers thereof or the pharmaceutical composition defined above to a subject diagnosed with, suffering from or at risk of developing said viral infection.
  • a method of inhibiting the RNA-dependent RNA polymerase activity of the enzyme NS5B, encoded by HCV comprising exposing the enzyme NS5B to an effective amount of the compound of formula (I) defined above and pharmaceutically acceptable salts, W-oxides, solvates, hydrates, racemates, enantiomers and isomers thereof.
  • a method of inhibiting HCV replication comprising exposing a cell infected with HCV to an effective amount of the compound of formula (I) defined above and pharmaceutically acceptable salts, W-oxides, solvates, hydrates, racemates, enantiomers and isomers thereof.
  • the present invention relates to compounds of formula (I) which inhibit viral polymerases and are useful in the treatment of Flaviviridae viral infections, particularly, hepatitis C (HCV).
  • HCV hepatitis C
  • the present invention relates to compounds of formula I, salts, N-oxides, racemates, enantiomers and isomers thereof as defined above.
  • R 1 is H or d- 6 alkyl, preferably methyl, ethyl or propyl, more preferably H or methyl and R 2 is H or R b , preferably H.
  • R 1 together with R 2 joins to form an optionally substituted 6-8 membered carbocyclic ring which may be optionally interrupted by one or more heteroatoms independently selected from O, N and S.
  • R 1 together with R 2 joins to form a 7- membered carbocycle.
  • R 2 together are a divalent linking moiety selected from the group consisting of -CH 2 CH 2 CH 2 -; -OCH 2 CH 2 -; -CH 2 OCH 2 -; - CH 2 CH 2 0-; -NCH 2 CH 2 -; -CH 2 NCH 2 -; and -CH 2 CH 2 N-, thereby joining to form a 7- membered carbocyclic ring together with the atoms to which R 1 and R 2 are attached the carbocyclic ring being optionally interrupted by O or N, preferably O.
  • R 2 together are a divalent linking moiety of formula - CH 2 CH 2 0-.
  • R 3 is an optionally substituted C 3 . 6 cycloalkyl group, preferably cyclohexyl.
  • A is a covalent bond and R 4 is C0 2 H or optionally substituted C0 2 Ci_ 6 alkyl.
  • X 2 and X 3 are each independently selected from N, CH, C-R c or C-A-R 4 provided that at least one of Xi , X 2 and X 3 is C-A-R 4 and A is a covalent bond and R 4 is C0 2 H or optionally substituted C0 2 C 1 . 6 alkyl.
  • X 1 is C-A-R 4 ;
  • X 2 and X 3 are each independently selected from N, CH or C-R c preferably N or CH.
  • X 2 is C-A-R 4 and X 1 and X 3 are each independently selected from N, CH or C-R c preferably N or CH.
  • X 3 is C-A-R 4 and X 1 and X 2 are each independently selected from N, CH or C-R c preferably N or CH.
  • R 4 is selected from H, C0 2 H and optionally substituted CO ⁇ . 6 alkyl.
  • R 4 is C0 2 H or CC ⁇ C ⁇ al yl, preferably C0 2 H or CO ⁇ . 3 alkyl, more preferably R 4 is selected from C0 2 H, C0 2 CH 3 and C0 2 CH 2 CH 3 .
  • A is a covalent bond
  • A is -CONH-C(R 5 )(R 6 )-B- wherein R 5 and R 6 are each independently selected from H, C ⁇ alkyl (preferably C ⁇ alkyl, more preferably methyl), C ⁇ 6 alkylaryl (preferably optionally substituted benzyl); C ⁇ alkylheterocyclyl and Ci_
  • alkylheteroaryl preferably CH 2 heteroaryl, wherein the heteroaryl is preferably a 5-, 6- or 9- membered heteroaryl, more preferably a 5-, 6- or 9-membered N-containing heteroaryl
  • R 5 and R 6 together with the carbon atom to which they are attached form a cyclobutyl group.
  • B is a covalent bond
  • B is -CONHR 7 - wherein R 7 is selected from aryl (preferably phenyl), arylC ⁇ alkyl (preferably phenylC ⁇ alkyl) and arylC 2 - 6 alkenyl (preferably phenylC 2 _ 3 alkenyl).
  • R 7 is phenylethenyl.
  • the compound of formula (I) is a compound of formula (la)
  • Z 3 is CH or C-R d and Ri , R 2 , R 3 , R d , X 2 and X 3 are as previously defined and salts, A/-oxides, solvates, hydrates, racemates, enantiomers and isomers thereof.
  • R d is selected from the group consisting of halo, OH, d_ 3 alkoxy or d_ 3 alkoxyaryl wherein the aryl is unsubstituted or substituted with heterocyclyl (preferably 5 or 6 membered heterocyclyl containing N such as morpholine or pyrrolidinone).
  • heterocyclyl preferably 5 or 6 membered heterocyclyl containing N such as morpholine or pyrrolidinone.
  • F, OH, OCH 3 and optionally substituted benzyloxy including unsubstituted benzyloxy and 2-(morpholin-4-yl)-5-(2-oxopyrrolidin-1 -yl)benzyloxy are particularly preferred R d groups when Z 3 is C-R d .
  • R ⁇ R 2 , R3, Z 3 ⁇ , X 2 and X 3 are as previously defined and salts, N-oxides, solvates, hydrates, racemates, enantiomers and isomers thereof.
  • A, R 2 , R3, R4, Z ⁇ X ⁇ , X2 and X 3 are as previously defined provided that A- R 4 is not H (i.e. where A is a covalent bond and R 4 is H) and salts, N-oxides, solvates, hydrates, racemates, enantiomers and isomers thereof
  • C h alky refers to optionally substituted straight chain or branched chain hydrocarbon groups having from 1 to 6 carbon atoms. Examples include methyl (Me), ethyl (Et), propyl (Pr), isopropyl (/-Pr), butyl (Bu), isobutyl (/-Bu), sec-butyl (s-Bu), tert-butyl (f-Bu), pentyl, neopentyl, hexyl and the like. Unless the context requires otherwise, the term “d. 6 alkyl” also encompasses alkyl groups containing one less hydrogen atom such that the group is attached via two positions i.e. divalent. and "C 1 .
  • alkyl including methyl, ethyl, propyl, /sopropyl, n-butyl, / ' so-butyl, sec-butyl and ferf-butyl are preferred with methyl being particularly preferred.
  • C 2 - 6 alkenyl refers to optionally substituted straight chain or branched chain hydrocarbon groups having at least one double bond of either E or Z stereochemistry where applicable and 2 to 6 carbon atoms. Examples include vinyl, 1 -propenyl, 1- and 2- butenyl and 2-methyl-2-propenyl. Unless the context requires otherwise, the term "C 2 .
  • alkenyl also encompasses alkenyl groups containing one less hydrogen atom such that the group is attached via two positions i.e. divalent.
  • C 2 - 4 alkenyl and “C 2 _ 3 alkenyl” including ethenyl, propenyl and butenyl are preferred with ethenyl being particularly preferred.
  • C 2 - 6 alkynyl refers to optionally substituted straight chain or branched chain hydrocarbon groups having at least one triple bond and 2 to 6 carbon atoms.
  • C 2 - 6 alkynyl also encompasses alkynyl groups containing one less hydrogen atom such that the group is attached via two positions i.e. divalent.
  • C 2 . 3 alkynyl is preferred.
  • C 3 . 8 cycloalkyl refers to non-aromatic cyclic groups having from 3 to 8 carbon atoms, including cyclopropyl, cyclobutyl, cyclopentyl, cyclohexyl, cycloheptyl and cyclooctyl. It will be understood that cycloalkyl groups may be saturated such as cyclohexyl or unsaturated such as cyclohexenyl.
  • C 3 . 6 cycloalkyl such as cyclopropyl, cyclobutyl, cyclopentyl and cyclohexyl are preferred.
  • hydroxy and "hydroxyl” refer to the group -OH.
  • Ci_ 6 alkoxy refers to an alkyl group as defined above covalently bound via an O linkage containing 1 to 6 carbon atoms, such as methoxy, ethoxy, propoxy, isoproxy, butoxy, tert-butoxy and pentoxy.
  • C 1 . 4 alkoxy and “C ⁇ alkoxy” including methoxy, ethoxy, propoxy and butoxy are preferred with methoxy being particularly preferred.
  • Ci_ 6 alkylhalo refers to a Ci_ 6 alkyl which is substituted with one or more halogens. d. 3 alkylhalo groups are preferred, such as for example, -CHF 2 and -CF 3 .
  • Ci_ 6 alkoxylhalo refers to a C ⁇ alkoxyl which is substituted with one or more halogens. d- 3 alkoxylhalo groups are preferred, such as for example, -OCHF 2 and - OCF 3 .
  • carboxylate or “carboxyl” refers to the group -COO " or -COOH.
  • esters refers to a carboxyl group having the hydrogen replaced with, for example a C ⁇ alkyl group (“carboxylCi. 6 alkyl” or “alkylester”), an aryl or aralkyl group (“arylester” or “aralkylester”) and so on.
  • C0 2 Ci_ 3 alkyl groups are preferred, such as for example, methylester (CO 2 Me), ethylester (C0 2 Et) and propylester (C0 2 Pr) and includes reverse esters thereof (e.g. -OCOMe, -OCOEt and -OCOPr).
  • cyano refers to the group -CN.
  • nitro refers to the group -N0 2 .
  • amino refers to the group -NH 2 .
  • substituted amino or “secondary amino” refers to an amino group having a hydrogen replaced with, for example a C ⁇ alkyl group (“C ⁇ alkylamino”), an aryl or aralkyl group (“arylamino", “aralkylamino”) and so on.
  • C ⁇ alkylamino groups are preferred, such as for example, methylamino (NHMe), ethylamino (NHEt) and propylam ino (NHPr).
  • disubstituted amino or "tertiary amino” refers to an amino group having the two hydrogens replaced with, for example a C ⁇ alkyl group, which may be the same or different (“dialkylamino"), an aryl and alkyl group (“aryl(alkyl)amino”) and so on.
  • D ' ⁇ (C ⁇ .
  • 3 alkyl)amino groups are preferred, such as for example, dimethylamino (NMe 2 ), diethylamino (NEt 2 ), dipropylamino (NPr 2 ) and variations thereof (e.g. N(Me)(Et) and so on).
  • NMe 2 dimethylamino
  • NEt 2 diethylamino
  • NPr 2 dipropylamino
  • variations thereof e.g. N(Me)(Et) and so on.
  • substituted acyl or “ketone” refers to an acyl group having a hydrogen replaced with, for example a C ⁇ alkyl group ("Ci. 6 alkylacyl” or “alkylketone” or “ketoalkyl”), an aryl group (“arylketone”), an aralkyl group (“aralkylketone) and so on. Ci_ 3 alkylacyl groups are preferred.
  • aminoacyl refers to the group -NHC(0)H.
  • substituted amido or “substituted amide” refers to an amido group having a hydrogen replaced with, for example a C ⁇ alkyl group ("Ci_ 6 alkylamido” or “Ci_ 6 alkylam ide”), an aryl (“arylamido”), aralkyl group (“aralkylamido”) and so on.
  • C ⁇ alkylamide groups are preferred, such as for example, methylamide (-C(O)NHMe), ethylamide (- C(O)NHEt) and propylamide (-C(O)NHPr) and includes reverse amides thereof (e.g. - NHMeC(O)-, -NHEtC(O)- and -NHPrC(O)-).
  • disubstituted amido or “disubstituted amide” refers to an amido group having the two hydrogens replaced with, for example a Ci_ 6 alkyl group ("d C ⁇ ealky amido” or “diiC ⁇ ealkylJamide”), an aralkyl and alkyl group ("alkyl(aralkyl)am ido") and so on.
  • Di(d. 3 alkyl)amide groups are preferred, such as for example, dimethylamide (-C(0)NMe 2 ), diethylamide (-C(0)NEt 2 ) and dipropylamide ((-C(0)NPr 2 ) and variations thereof (e.g. - C(0)N(Me)Et and so on) and includes reverse amides thereof.
  • thiol refers to the group -SH.
  • Ci_ 6 alkylthio refers to a thiol group having the hydrogen replaced with a Ci- 6 alkyl group.
  • Ci_ 3 alkylthio groups are preferred, such as for example, thiolmethyl, thiolethyl and thiolpropyl.
  • substituted sulfinyl or “sulfoxide” refers to a sulfinyl group having the hydrogen replaced with, for example a C ⁇ alkyl group ("C ⁇ alkylsulfinyl” or "Ci_
  • alkylsulfoxide an aryl (“arylsulfinyl”), an aralkyl (“aralkyl sulfinyl”) and so on.
  • d_ 3 alkylsulf inyl groups are preferred, such as for example, -SOmethyl, -SOethyl and - SOpropyl.
  • sulfonyl refers to the group -S0 2 H.
  • substituted sulfonyl refers to a sulfonyl group having the hydrogen replaced with, for example a C ⁇ alkyl group (“sulfonylC ⁇ ealkyl”), an aryl (“arylsulfonyl”), an aralkyl (“aralkylsulfonyl”) and so on.
  • SulfonylC ⁇ alkyl groups are preferred, such as for example, -S0 2 Me, -S0 2 Et and -S0 2 Pr.
  • sulfonylamido or "sulfonamide” refers to the group -S0 2 NH 2 .
  • substituted sulfonamido or “substituted sulphonamide” refers to an sulfonylamido group having a hydrogen replaced with, for example a C ⁇ alkyl group
  • SulfonylamidoCi. 6 alkyl an aryl (“arylsulfonamide”), aralkyl (“aralkylsulfonamide”) and so on.
  • SulfonylamidoC ⁇ alkyl groups are preferred, such as for example, -S0 2 NHMe, - S0 2 NHEt and -S0 2 NHPr and includes reverse sulfonamides thereof (e.g. -NHS0 2 Me, - NHS0 2 Et and -NHS0 2 Pr).
  • disubstituted sufonamido or “disubstituted sulphonamide” refers to an sulfonylamido group having the two hydrogens replaced with, for example a C ⁇ alkyl group, which may be the same or different ("sulfonylamidodi(C 1 . 6 alkyl)"), an aralkyl and alkyl group ("sulfonamido(aralkyl)alkyl”) and so on.
  • Sulfonylamidod C ⁇ alkyl) groups are preferred, such as for example, -S0 2 NMe 2 , -S0 2 NEt 2 and -S0 2 NPr 2 and variations thereof (e.g. - S0 2 N(Me)Et and so on) and includes reserve sulfonamides thereof.
  • sulfate refers to the group OS(0) 2 OH and includes groups having the hydrogen replaced with, for example a C 1 . 6 alkyl group ("alkylsulfates”), an aryl (“arylsulfate”), an aralkyl (“aralkylsulfate”) and so on. ( ⁇ sulfates are preferred, such as for example, OS(0) 2 OMe, OS(0) 2 OEt and OS(0) 2 OPr.
  • sulfonate refers to the group S0 3 H and includes groups having the hydrogen replaced with, for example a C 1 . 6 alkyl group (“alkylsulfonate”), an aryl
  • arylsulfonate an aralkyl
  • aralkylsulfonate an aralkyl
  • aryl refers to a carbocyclic (non-heterocyclic) aromatic ring or mono-, bi- or tri-cyclic ring system.
  • the aromatic ring or ring system is generally composed of 6 to 10 carbon atoms.
  • aryl groups include but are not limited to phenyl, biphenyl, naphthyl and tetrahydronaphthyl. 6-membered aryls such as phenyl are preferred.
  • alkylaryl refers to C ⁇ alkylaryl such as benzyl.
  • alkoxyaryl refers to Ci_
  • 6alkyloxyaryl such as benzyloxy.
  • heterocyclyl refers to a moiety obtained by removing a hydrogen atom from a ring atom of a heterocyclic compound which moiety has from 3 to 10 ring atoms (unless otherwise specified), of which 1 , 2, 3 or 4 are ring heteroatoms each heteroatom being independently selected from O, S and N.
  • the prefixes 3-, 4-, 5-, 6-, 7-, 8-, 9- and 10- membered denote the number of ring atoms, or range of ring atoms, whether carbon atoms or heteroatoms.
  • the term "3-10 membered heterocylyl”, as used herein, pertains to a heterocyclyl group having 3, 4, 5, 6, 7, 8, 9 or 10 ring atoms.
  • heterocylyl groups include 5- 6-membered monocyclic heterocyclyls and 9-10 membered fused bicyclic heterocyclyls.
  • Examples of monocyclic heterocyclyl groups include, but are not limited to, those containing one nitrogen atom such as aziridine (3-membered ring), azetidine (4-membered ring), pyrrolidine (tetrahydropyrrole), pyrroline (e.g., 3-pyrroline, 2,5-dihydropyrrole), 2H- pyrrole or 3H-pyrrole (isopyrrole, isoazole) or pyrrolidinone (5-membered rings) , piperidine, dihydropyridine, tetrahydropyridine (6-membered rings), and azepine (7-membered ring); those containing two nitrogen atoms such as imidazoline, pyrazolidine (diazolidine), imidazoline, pyrazoline (dihydropyrazole) (5-membered rings), piperazine (6-membered ring); those containing one oxygen atom such as oxirane (3-membered
  • Heterocyclyls also encompass aromatic heterocyclyls and non-aromatic heterocyclyls. Such groups may be substituted or unsubstituted.
  • aromatic heterocyclyl may be used interchangeably with the term “heteroaromatic” or the term “heteroaryl” or “hetaryl”.
  • the heteroatoms in the aromatic heterocyclyl group may be independently selected from N, S and O.
  • Heteroaryl is used herein to denote a heterocyclic group having aromatic character and embraces aromatic monocyclic ring systems and polycyclic (e.g. bicyclic) ring systems containing one or more aromatic rings.
  • aromatic heterocyclyl also encompasses pseudoaromatic heterocyclyls.
  • aromatic heterocyclyl refers to a ring system which is not strictly aromatic, but which is stabilized by means of delocalization of electrons and behaves in a similar manner to aromatic rings.
  • aromatic heterocyclyl therefore covers polycyclic ring systems in which all of the fused rings are aromatic as well as ring systems where one or more rings are non-aromatic, provided that at least one ring is aromatic. In polycyclic systems containing both aromatic and non-aromatic rings fused together, the group may be attached to another moiety by the aromatic ring or by a non- aromatic ring.
  • heteroaryl groups are monocyclic and bicyclic groups containing from five to ten ring members.
  • the heteroaryl group can be, for example, a five membered or six membered monocyclic ring or a bicyclic structure formed from fused five and six membered rings or two fused six membered rings or two fused five membered rings.
  • Each ring may contain up to about four heteroatoms typically selected from nitrogen, sulphur and oxygen.
  • the heteroaryl ring will contain up to 4 heteroatoms, more typically up to 3 heteroatoms, more usually up to 2, for example a single heteroatom.
  • the heteroaryl ring contains at least one ring nitrogen atom.
  • the nitrogen atoms in the heteroaryl rings can be basic, as in the case of an imidazole or pyridine, or essentially non-basic as in the case of an indole or pyrrole nitrogen.
  • the number of basic nitrogen atoms present in the heteroaryl group, including any amino group substituents of the ring, will be less than five.
  • Aromatic heterocyclyl groups may be 5-membered or 6-membered mono-cyclic aromatic ring systems.
  • 5-membered monocyclic heteroaryl groups include but are not limited to furanyl, thienyl, pyrrolyl, oxazolyl, oxadiazolyl (including 1 ,2,3 and 1 ,2,4 oxadiazolyls and furazanyl i.e.
  • thiazolyl isoxazolyl, isothiazolyl, pyrazolyl, imidazolyl, triazolyl (including 1 ,2,3, 1 ,2,4 and 1 ,3,4 triazolyls), oxatriazolyl, tetrazolyl, thiadiazolyl (including 1 ,2,3 and 1 ,3,4 thiadiazolyls) and the like.
  • 6-membered monocyclic heteroaryl groups include but are not limited to pyridinyl, pyrimidinyl, pyridazinyl, pyrazinyl, triazinyl, pyranyl, oxazinyl, dioxinyl, thiazinyl, thiadiazinyl and the like.
  • 6-membered aromatic heterocyclyls containing nitrogen include pyridyl (1 nitrogen), pyrazinyl, pyrimidinyl and pyridazinyl (2 nitrogens).
  • Aromatic heterocyclyl groups may also be bicyclic or polycyclic heteroaromatic ring systems such as fused ring systems (including purine, pteridinyl, napthyridinyl, 1 H thieno[2,3-c]pyrazolyl, thieno[2,3-b]furyl and the like) or linked ring systems (such as oligothiophene, polypyrrole and the like).
  • fused ring systems including purine, pteridinyl, napthyridinyl, 1 H thieno[2,3-c]pyrazolyl, thieno[2,3-b]furyl and the like
  • linked ring systems such as oligothiophene, polypyrrole and the like.
  • Fused ring systems may also include aromatic 5- membered or 6-membered heterocyclyls fused to carbocyclic aromatic rings such as phenyl, napthyl, indenyl, azulenyl, fluorenyl, anthracenyl and the like, such as 5-membered aromatic heterocyclyls containing nitrogen fused to phenyl rings, 5-membered aromatic heterocyclyls containing 1 or 2 nitrogens fused to phenyl ring.
  • aromatic 5- membered or 6-membered heterocyclyls fused to carbocyclic aromatic rings such as phenyl, napthyl, indenyl, azulenyl, fluorenyl, anthracenyl and the like, such as 5-membered aromatic heterocyclyls containing nitrogen fused to phenyl rings, 5-membered aromatic heterocyclyls containing 1 or 2 nitrogens fused to phenyl ring.
  • a bicyclic heteroaryl group may be, for example, a group selected from: a) a benzene ring fused to a 5- or 6-membered ring containing 1 , 2 or 3 ring heteroatoms; b) a pyridine ring fused to a 5- or 6-membered ring containing 1 , 2 or 3 ring heteroatoms; c) a pyrimidine ring fused to a 5- or 6-membered ring containing 1 or 2 ring heteroatoms; d) a pyrrole ring fused to a 5- or 6-membered ring containing 1 , 2 or 3 ring heteroatoms; e) a pyrazole ring fused to a 5- or 6-membered ring containing 1 or 2 ring heteroatoms; f) an imidazole ring fused to a 5- or 6-membered ring containing 1 or 2 ring heteroatoms; g) an oxazole ring fused to a 5-
  • bicyclic heteroaryl groups containing a five membered ring fused to another five membered ring include but are not limited to imidazothiazole (e.g. imidazo[2, 1-b]thiazole) and imidazoimidazole (e.g. imidazo[1 ,2-a]imidazole).
  • imidazothiazole e.g. imidazo[2, 1-b]thiazole
  • imidazoimidazole e.g. imidazo[1 ,2-a]imidazole
  • bicyclic heteroaryl groups containing a six membered ring fused to a five membered ring include but are not limited to benzofuran, benzothiophene, benzimidazole, benzoxazole, isobenzoxazole, benzisoxazole, benzothiazole,
  • benzisothiazole isobenzofuran, indole, isoindole, indolizine, indoline, isoindoline, purine (e.g., adenine, guanine), indazole, pyrazolopyrimidine (e.g. pyrazolo[1 ,5-a]pyrimidine), benzodioxole and pyrazolopyridine (e.g. pyrazolo[1 ,5-a]pyridine) groups.
  • a further example of a six membered ring fused to a five membered ring is a pyrrolopyridine group such as a pyrrolo[2,3-b]pyridine group.
  • bicyclic heteroaryl groups containing two fused six membered rings include but are not limited to quinoline, isoquinoline, chroman, thiochroman, chromene, isochromene, isochroman, benzodioxan, quinolizine, benzoxazine, benzodiazine, pyridopyridine, quinoxaline, quinazoline, cinnoline, phthalazine, naphthyridine and pteridine groups.
  • heteroaryl groups containing an aromatic ring and a non-aromatic ring include tetrahydronaphthalene, tetrahydroisoquinoline, tetrahydroquinoline,
  • aromatic heterocyclyls fused to carbocyclic aromatic rings may therefore include but are not limited to benzothiophenyl, indolyl, isoindolyl, benzofuranyl, isobenzofuranyl, benzimidazolyl, indazolyl, benzoxazolyl, benzisoxazolyl, isobenzoxazoyi, benzothiazolyl, benzisothiazolyl, quinolinyl, isoquinolinyl, quinoxalinyl, quinazolinyl, cinnolinyl, benzotriazinyl, phthalazinyl, carbolinyl and the like.
  • non-aromatic heterocyclyl encompasses optionally substituted saturated and unsaturated rings which contain at least one heteroatom selected from the group consisting of N, S and O.
  • Non-aromatic heterocyclyls may be 3-7 membered mono-cyclic rings.
  • Examples of 5-membered non-aromatic heterocyclyl rings include 2H-pyrrolyl, 1 - pyrrolinyl, 2-pyrrolinyl, 3-pyrrolinyl, pyrrolidinyl, 1 -pyrrolidinyl, 2-pyrrolidinyl, 3-pyrrolidinyl, tetrahydrofuranyl, tetrahydrothiophenyl, pyrazolinyl, 2-pyrazolinyl, 3-pyrazolinyl, pyrazolidinyl, 2-pyrazolidinyl, 3-pyrazolidinyl, imidazolidinyl, 3-dioxalanyl, thiazolidinyl, isoxazolidinyl, 2-imidazolinyl and the like.
  • 6-membered non-aromatic heterocyclyls include piperidinyl, piperidinonyl, pyranyl, dihyrdopyranyl, tetrahydropyranyl, 2H pyranyl, 4H pyranyl, thianyl, thianyl oxide, thianyl dioxide, piperazinyl, diozanyl, 1 ,4-dioxinyl, 1 ,4-dithianyl, 1 ,3,5- triozalanyl, 1 ,3,5-trithianyl, 1 ,4-morpholinyl, thiomorpholinyl, 1 ,4-oxathianyl, triazinyl, 1 ,4- thiazinyl and the like.
  • Examples of 7-membered non-aromatic heterocyclyls include azepanyl, oxepanyl, thiepanyl and the like.
  • Non-aromatic heterocyclyl rings may also be bicyclic heterocyclyl rings such as linked ring systems (for example uridinyl and the like) or fused ring systems.
  • Fused ring systems include non-aromatic 5-membered, 6-membered or 7-membered heterocyclyls fused to carbocyclic aromatic rings such as phenyl, napthyl, indenyl, azulenyl, fluorenyl, anthracenyl and the like.
  • Examples of non-aromatic 5-membered, 6-membered or 7- membered heterocyclyls fused to carbocyclic aromatic rings include indolinyl,
  • halo refers to fluoro, chloro, bromo or iodo.
  • the term "optionally substituted” or “optional substituent” as used herein refers to a group which may or may not be further substituted with 1 , 2, 3, 4 or more groups, preferably 1 , 2 or 3, more preferably 1 or 2 groups selected from the group consisting of Chalky!, C 2 - 6 alkenyl, C 2 - 6 alkynyl, C 3 .
  • suitable derivatives of aromatic heterocyclyls containing nitrogen include W-oxides thereof.
  • the compounds of the invention may also be prepared as salts which are pharmaceutically acceptable, but it will be appreciated that non-pharmaceutically acceptable salts also fall within the scope of the present invention, since these are useful as
  • pharmaceutically acceptable salts include salts of pharmaceutically acceptable cations such as sodium , potassium, lithium, calcium, magnesium, ammonium and alkylamimonium; acid addition salts of pharmaceutically acceptable inorganic acids such as hydrochloric, orthophosphoric, sulfuric, phosphoric, nitric, carbonic, boric, sulfamic and hydrobromic acids; or salts of pharmaceutically acceptable organic acids such as acetic, propionic, butyric, tartaric, maleic, hydroxymaleic, fumaric, citric, lactic, mucic, gluconic, benzoic, succinic, oxalic, phenylacetic, methanesulfonic, trihalomethanesulfonic, toluenesulfonic,
  • Salts of amine groups may also comprise quaternary ammonium salts in which the amino nitrogen atom carries a suitable organic group such as an alkyl, alkenyl, alkynyl or aralkyl moiety.
  • the salts may be formed by conventional means, such as by reacting the free base form of the compound with one or more equivalents of the appropriate acid.
  • a reference to a pharmaceutically acceptable salt includes the solvent addition forms or crystal forms thereof, particularly solvates or polymorphs.
  • Solvates contain either stoichiometric or non-stoichiometric amounts of a solvent, and may be formed during the process of crystallization with pharmaceutically acceptable solvents such as water, alcohols such as methanol, ethanol or isopropyl alcohol, DMSO, acetonitrile, dimethyl formamide (DMF) and the like with the solvate forming part of the crystal lattice by either non-covalent binding or by occupying a hole in the crystal lattice. Hydrates are formed when the solvent is water, alcoholates are formed when the solvent is alcohol.
  • Solvates of the compounds of the present invention can be conveniently prepared or formed during the processes described herein.
  • the compounds of the present invention can exist in unsolvated as well as solvated forms.
  • the solvated forms are considered equivalent to the unsolvated forms for the purposes of the compounds and methods provided herein.
  • the compounds of the present invention can exist in unsolvated as well as solvated forms with pharmaceutically acceptable solvents such as water, ethanol, and the like.
  • pharmaceutically acceptable solvents such as water, ethanol, and the like.
  • the solvated forms of the compounds of the present invention are also considered to be disclosed herein.
  • compounds of formula (I) may possess a chiral centre and may therefore exist as an isomer such as a racemate or an R- or S- enantiomer.
  • the compounds may therefore be used as a purified enantiomer or diastereomer, or as a mixture of any ratio thereof.
  • the isomers may be separated conventionally by chromatographic methods or using a resolving agent. Alternatively the individual isomers may be prepared by asymmetric synthesis using chiral intermediates. Where the compound has a carbon- carbon double bond, it may occur in Z- or E- form and all isomeric forms of the compounds being included in the present invention.
  • This invention also encompasses prodrugs of the compounds of formula (I).
  • pro-drug is used herein in its broadest sense to include those compounds which are converted in vivo to the compound of formula (I).
  • Use of the prodrug strategy optimises the delivery of the drug to its site of action.
  • the compounds of formula (I) having carboxylic esters may act as prodrug moieties with respect to their corresponding carboxylic acid analogues.
  • RNA dependent RNA polymerase of HCV RNA dependent RNA polymerase of HCV
  • HCV NS5B polymerase which is the viral RNA-dependent RNA polymerase (RdRp) that is responsible for viral replications.
  • RdRp viral RNA-dependent RNA polymerase
  • HCV NS5B protein is released from a polyprotein and is involved in the synthesis of double-stranded RNA from a single-stranded viral RNA genome. It is believed that the replication and/or reproduction of HCV virus may be inhibited or prevented through the inhibition of NS5B polymerase and suppress or prevent the formation of the double- stranded HCV RNA.
  • the compounds of formula (I) act by specific inhibition of NS5B polymerase, the compounds may be tested for the lack of inhibitory activity in an assay measuring the activity of an RNA-dependent RNA polymerase other than HCV polymerase or in a DNA dependent RNA polymerase assay.
  • the invention also provides a pharmaceutical composition
  • a pharmaceutical composition comprising a compound of formula (I) and a pharmaceutically acceptable carrier.
  • the pharmaceutical composition may further comprise or be administered in combination with one or more other antiviral agents such as Ribavirin (Copegus® or Rebetol®), an antiviral nucleoside inhibitor of NS5B polymerase (such as 4-amino-7-(2-C-methyl- -D-ribofuranosyl)-pyrrolo[2, 1-f][1 ,2,4]triazine; PSI-7977; PSI-938; RG7128 or mericitabine; IDX-184; INX-189 and other such agents that may be developed) a non-nucleoside inhibitor of NS5B polymerase (such as GS-9190 or tegobuvir; PF-868554 or filibuvir; VX-222; IDX-375; ABT-072; ABT-333; ANA-598 or setrobuvir;
  • the composition may also additionally comprise at least one immunomodulatory agent for example an interferon or interferon derivative such as interferon alpha 2B (such as Intron® A interferon available from Schering Corp., Kenilworth, N.J.), pegylated interferon alpha 2A (such as Pegasys® available from Hoffmann-LaRoche, Nutley, N.J.), pegylated interferon alpha 2B (such as Peg-lntron® available from Schering Corp.
  • interferon alpha 2B such as Intron® A interferon available from Schering Corp., Kenilworth, N.J.
  • pegylated interferon alpha 2A such as Pegasys® available from Hoffmann-LaRoche, Nutley, N.J.
  • pegylated interferon alpha 2B such as Peg-lntron® available from Schering Corp.
  • the other antiviral agent is Ribavarin optionally in combination with peg/I FN.
  • the other antiviral agent is an NS5B inhibitor, more particularly a nucleoside inhibitor such as the bicyclic nucleosides and nucleotides of the general formula described in WO2010/002877, for example, 4-amino-7-(2-C-methyl-3-D- ribofuranosyl)-pyrrolo[2, 1-f][1 ,2,4]triazine.
  • the other antiviral agent is an NS3/4A protease inhibitor such as telaprevir (VX-950) or Incivek®; boceprevir or Victrelis®; BI-201335; TMC-435; RG- 7227 or danoprevir; MK-7009 or vaniprevir; GS-9451 ; GS-9256; BMS-650032; ACH-1625; ACH-2684; MK-5172; ABT-450; IDX-320; SCH-900518, particularly telaprevir (VX-950).
  • VX-950 NS3/4A protease inhibitor
  • the other antiviral agent is an NS5A inhibitor such as BMS-790052 (daclatasvir); GS-5885; ABT-267; PPI-461 ; ACH-2928; GSK2336805, particularly BMS-790052 (daclatasvir).
  • composition is intended to include the formulation of an active ingredient with conventional carriers and excipients, and also with encapsulating materials as the carrier, to give a capsule in which the active ingredient (with or without other carriers) is surrounded by the encapsulation carrier.
  • Any carrier must be “pharmaceutically acceptable” meaning that it is compatible with the other ingredients of the composition and is not deleterious to a subject.
  • compositions of the present invention may contain other therapeutic agents as described above, and may be formulated, for example, by employing conventional solid or liquid vehicles or diluents, as well as pharmaceutical additives of a type appropriate to the mode of desired administration (for example, excipients, binders, preservatives, stabilizers, flavours, etc.) according to techniques such as those well known in the art of pharmaceutical formulation (See, for example, Remington: The Science and Practice of Pharmacy, 21st Ed. , 2005, Lippincott Williams & Wilkins).
  • the pharmaceutical composition includes those suitable for oral, rectal, nasal, topical (including buccal and sub-lingual), vaginal or parenteral (including intramuscular, sub-cutaneous and intravenous) administration or in a form suitable for administration by inhalation or insufflation.
  • compositions and unit dosages thereof may thus be placed into the form of pharmaceutical compositions and unit dosages thereof, and in such form may be employed as solids, such as tablets or filled capsules, or liquids such as solutions, suspensions, emulsions, elixirs, or capsules filled with the same, all for oral use, in the form of suppositories for rectal administration ; or in the form of sterile injectable solutions for parenteral (including subcutaneous) use.
  • Such pharmaceutical compositions and unit dosage forms thereof may comprise conventional ingredients in conventional proportions, with or without additional active compounds or principles, and such unit dosage forms may contain any suitable effective amount of the active ingredient commensurate with the intended daily dosage range to be employed.
  • pharmaceutically acceptable carriers can be either solid or liquid.
  • Solid form preparations include powders, tablets, pills, capsules, cachets, suppositories, and dispensable granules.
  • a solid carrier can be one or more substances which may also act as diluents, flavouring agents, solubilisers, lubricants, suspending agents, binders, preservatives, tablet disintegrating agents, or an encapsulating material.
  • Suitable carriers are magnesium carbonate, magnesium stearate, talc, sugar, lactose, pectin, dextrin, starch, gelatin, tragacanth, methylcellulose, sodium
  • carboxymethylcellulose a low melting wax, cocoa butter, and the like.
  • preparation is intended to include the formulation of the active compound with
  • encapsulating material as carrier providing a capsule in which the active component, with or without carriers, is surrounded by a carrier, which is thus in association with it.
  • a carrier which is thus in association with it.
  • cachets and lozenges are included. Tablets, powders, capsules, pills, cachets, and lozenges can be used as solid forms suitable for oral administration.
  • Liquid form preparations include solutions, suspensions, and emulsions, for example, water or water-propylene glycol solutions.
  • parenteral injection liquid preparations can be formulated as solutions in aqueous polyethylene glycol solution.
  • Sterile liquid form compositions include sterile solutions, suspensions, emulsions, syrups and elixirs.
  • the active ingredient can be dissolved or suspended in a
  • pharmaceutically acceptable carrier such as sterile water, sterile organic solvent or a mixture of both.
  • compositions according to the present invention may thus be formulated for parenteral administration (e. g. by injection, for example bolus injection or continuous infusion) and may be presented in unit dose form in ampoules, pre-filled syringes, small volume infusion or in multi-dose containers with an added preservative.
  • the compositions may take such forms as suspensions, solutions, or emulsions in oily or aqueous vehicles, and may contain formulation agents such as suspending, stabilising and/or dispersing agents.
  • the active ingredient may be in powder form, obtained by aseptic isolation of sterile solid or by lyophilisation from solution, for constitution with a suitable vehicle, e.g. sterile, pyrogen-free water, before use.
  • compositions suitable for injectable use include sterile injectable solutions or dispersions, and sterile powders for the extemporaneous preparation of sterile injectable solutions. They should be stable under the conditions of manufacture and storage and may be preserved against oxidation and the contaminating action of microorganisms such as bacteria or fungi.
  • the solvent or dispersion medium for the injectable solution or dispersion may contain any of the conventional solvent or carrier systems for the compounds, and may contain, for example, water, ethanol, polyol (for example, glycerol, propylene glycol and liquid polyethylene glycol, and the like), suitable mixtures thereof, and vegetable oils.
  • polyol for example, glycerol, propylene glycol and liquid polyethylene glycol, and the like
  • compositions suitable for injectable use may be delivered by any appropriate route including intravenous, intramuscular, intracerebral, intrathecal, epidural injection or infusion.
  • Sterile injectable solutions are prepared by incorporating the active compounds in the required amount in the appropriate solvent with various other ingredients such as these enumerated above, as required, followed by filtered sterilization.
  • dispersions are prepared by incorporating the various sterilised active ingredient into a sterile vehicle which contains the basic dispersion medium and the required other ingredients from those enumerated above.
  • preferred methods of preparation are vacuum drying or freeze-drying of a previously sterile-filtered solution of the active ingredient plus any additional desired ingredients.
  • the active ingredients When the active ingredients are suitably protected they may be orally administered, for example, with an inert diluent or with an assimilable edible carrier, or it may be enclosed in hard or soft shell gelatin capsule, or it may be compressed into tablets, or it may be incorporated directly with the food of the diet.
  • the active compound may be incorporated with excipients and used in the form of ingestible tablets, buccal tablets, troches, capsules, elixirs, suspensions, syrups, wafers, and the like.
  • the amount of active compound in therapeutically useful compositions should be sufficient that a suitable dosage will be obtained.
  • the tablets, troches, pills, capsules and the like may also contain the components as listed hereafter: a binder such as gum, acacia, corn starch or gelatin; excipients such as dicalcium phosphate; a disintegrating agent such as corn starch, potato starch, alginic acid and the like; a lubricant such as magnesium stearate; and a sweetening agent such a sucrose, lactose or saccharin may be added or a flavouring agent such as peppermint, oil of wintergreen, or cherry flavouring.
  • a binder such as gum, acacia, corn starch or gelatin
  • excipients such as dicalcium phosphate
  • a disintegrating agent such as corn starch, potato starch, alginic acid and the like
  • a lubricant such as magnesium stearate
  • a sweetening agent such as sucrose, lactose or saccharin may be added or a flavouring agent such as peppermint, oil of winter
  • tablets, pills, or capsules may be coated with shellac, sugar or both.
  • a syrup or elixir may contain the active compound, sucrose as a sweetening agent, methyl and propylparabens as preservatives, a dye and flavouring such as cherry or orange flavour.
  • any material used in preparing any dosage unit form should be pharmaceutically pure and substantially non-toxic in the amounts employed.
  • the active compound (s) may be incorporated into sustained-release preparations and formulations, including those that allow specific delivery of the active peptide to specific regions of the gut.
  • Aqueous solutions suitable for oral use can be prepared by dissolving the active component in water and adding suitable colorants, flavours, stabilising and thickening agents, as desired.
  • Aqueous suspensions suitable for oral use can be made by dispersing the finely divided active component in water with viscous material, such as natural or synthetic gums, resins, methylcellulose, sodium carboxymethylcellulose, or other well known suspending agents.
  • Pharmaceutically acceptable carriers and/or diluents include any and all solvents, dispersion media, coatings, antibacterial and antifungal agents, isotonic and absorption delaying agents and the like.
  • solid form preparations that are intended to be converted, shortly before use, to liquid form preparations for oral administration.
  • liquid forms include solutions, suspensions, and emulsions.
  • These preparations may contain, in addition to the active component, colorants, flavours, stabilisers, buffers, artificial and natural sweeteners, dispersants, thickeners, solubilising agents, and the like.
  • the compounds according to the invention may be formulated as ointments, creams or lotions, or as a transdermal patch.
  • Ointments and creams may, for example, be formulated with an aqueous or oily base with the addition of suitable thickening and/or gelling agents.
  • Lotions may be formulated with an aqueous or oily base and will in general also contain one or more emulsifying agents, stabilising agents, dispersing agents, suspending agents, thickening agents, or colouring agents.
  • Formulations suitable for topical administration in the mouth include lozenges comprising active agent in a flavoured base, usually sucrose and acacia or tragacanth; pastilles comprising the active ingredient in an inert base such as gelatin and glycerin or sucrose and acacia; and mouthwashes comprising the active ingredient in a suitable liquid carrier.
  • Solutions or suspensions are applied directly to the nasal cavity by conventional means, for example with a dropper, pipette or spray.
  • the formulations may be provided in single or multidose form. In the latter case of a dropper or pipette, this may be achieved by the patient administering an appropriate, predetermined volume of the solution or suspension.
  • the compounds according to the invention may be encapsulated with cyclodextrins, or formulated with other agents expected to enhance delivery and retention in the nasal mucosa.
  • Administration to the respiratory tract may also be achieved by means of an aerosol formulation in which the active ingredient is provided in a pressurised pack with a suitable propellant such as a chlorofluorocarbon (CFC) for example dichlorodifluoromethane, trichlorofluoromethane, or dichlorotetrafluoroethane, carbon dioxide, or other suitable gas.
  • a suitable propellant such as a chlorofluorocarbon (CFC) for example dichlorodifluoromethane, trichlorofluoromethane, or dichlorotetrafluoroethane, carbon dioxide, or other suitable gas.
  • CFC chlorofluorocarbon
  • the aerosol may conveniently also contain a surfactant such as lecithin.
  • a surfactant such as lecithin.
  • the dose of drug may be controlled by provision of a metered valve.
  • the active ingredients may be provided in the form of a dry powder, for example a powder mix of the compound in a suitable powder base such as lactose, starch, starch derivatives such as hydroxypropylmethyl cellulose and polyvinylpyrrolidone (PVP).
  • a powder base such as lactose, starch, starch derivatives such as hydroxypropylmethyl cellulose and polyvinylpyrrolidone (PVP).
  • PVP polyvinylpyrrolidone
  • the powder carrier will form a gel in the nasal cavity.
  • the powder composition may be presented in unit dose form for example in capsules or cartridges of, e. g. gelatin, or blister packs from which the powder may be administered by means of an inhaler.
  • the compound In formulations intended for administration to the respiratory tract, including intranasal formulations, the compound will generally have a small particle size for example of the order of 5 to 10 microns or less. Such a particle size may be obtained by means known in the art, for example by micronisation.
  • formulations adapted to give sustained release of the active ingredient may be employed.
  • the pharmaceutical preparations are preferably in unit dosage forms.
  • the preparation is subdivided into unit doses containing appropriate quantities of the active component.
  • the unit dosage form can be a packaged preparation, the package containing discrete quantities of preparation, such as packeted tablets, capsules, and powders in vials or ampoules.
  • the unit dosage form can be a capsule, tablet, cachet, or lozenge itself, or it can be the appropriate number of any of these in packaged form.
  • Dosage unit form refers to physically discrete units suited as unitary dosages for the subjects to be treated; each unit containing a predetermined quantity of active material calculated to produce the desired therapeutic effect in association with the required pharmaceutical carrier.
  • the specification for the dosage unit forms are dictated by and directly dependent on (a) the unique characteristics of the active material and the particular therapeutic effect to be achieved, and (b) the limitations inherent in the art of compounding such an active material for the treatment of a HCV viral infection in living subjects having a diseased condition in which bodily health is impaired.
  • the invention also includes the compounds in the absence of carrier where the compounds are in unit dosage form.
  • compositions comprising compounds of the invention formulated for oral delivery either alone or in combination with another HCV antiviral agent are particularly preferred.
  • the compounds of formula (I) may be used in the treatment of a Flaviviridae viral infection such as a HCV infection.
  • the term "treatment" means affecting a subject, tissue or cell to obtain a desired pharmacological and/or physiological effect and includes: (a) inhibiting the viral infection, i.e. arresting its development or further development; (b) relieving or ameliorating the effects of the viral infection, i.e. cause regression of the effects of the viral infection; (c) reducing the incidence or the viral infection or (d) preventing the infection from occurring in a subject, tissue or cell predisposed to the viral infection disease or at risk thereof, but has not yet been diagnosed with a protective pharmacological and/or physiological effect so that the viral infection does not develop or occur in the subject, tissue or cell.
  • the prevention of hepatitis C means, for example, administration of a
  • subject refers to any animal, in particular mammals such as humans having a disease or condition which requires treatment with the compound of formula (I).
  • administering refers to providing the compound or pharmaceutical composition of the invention to a subject suffering from or at risk of the diseases or conditions to be treated or prevented.
  • viral infection refers to the introduction of a virus into cells or tissues, e.g., hepatitis C virus (HCV). In general, the introduction of a virus is also associated with replication. Viral infection may be determined by measuring virus antibody titer in samples of a biological fluid, such as blood, using, e.g., enzyme immunoassay. Other suitable diagnostic methods include molecular based techniques, such as RT-PC , direct hybrid capture assay, nucleic acid sequence based amplification, and the like. A virus may infect an organ, e.g., liver, and cause disease, e.g. , hepatitis, cirrhosis, chronic liver disease and hepatocellular carcinoma.
  • HCV hepatitis C virus
  • Flaviviridae virus refers to a virus of the family Flaviviridae, which family includes the Hepacivirus Flavivirus and Pestivirus or hepatitis C-like virus genera.
  • a representative species of the genus of hepatitis C-like viruses is hepatitis C virus.
  • terapéuticaally effective amount refers to the amount of the compound of formula (I) that will elicit the biological or medical response of a subject, tissue or cell that is being sought by the researcher, veterinarian, medical doctor or other clinician.
  • an appropriate dosage level will generally be about 0.01 to 500 mg per kg subject body weight per day which can be administered in single or multiple doses.
  • the dosage level will be about 0.1 to about 250 mg/kg per day; more preferably about 0.5 to about 100 mg/kg per day.
  • a suitable dosage level may be about 0.01 to 250 mg/kg per day, about 0.05 to 100 mg/kg per day, or about 0.1 to 50 mg/kg per day. Within this range the dosage may be 0.05 to 0.5, 0.5 to 5 or 5 to 50 mg/kg per day.
  • the dosage may be selected, for example to any dose within any of these ranges, for therapeutic efficacy and/or symptomatic adjustment of the dosage to the subject to be treated
  • the dosage forms and levels may be formulated for either concurrent, sequential or separate administration or a combination thereof.
  • each moiety having a substitutable hydrogen such as for example, alkyl, alkenyl, alkynyl, alkoxy, cycloalkyl, cycloalkenyl, heterocyclyl, aryl and heteroaryl, in each occurrence as described in the general schemes and methods which follow may be optionally substituted.
  • substitutable hydrogen such as for example, alkyl, alkenyl, alkynyl, alkoxy, cycloalkyl, cycloalkenyl, heterocyclyl, aryl and heteroaryl, in each occurrence as described in the general schemes and methods which follow may be optionally substituted.
  • the particular examples which are described herein may undergo further functionalisation using methods known in the art, for example, compounds comprising amino groups or acid groups may undergo reduction amination or amide couplings respectively to form further examples of compounds of the invention.
  • compounds of formula (II) are prepared by heating a suitable amino- substituted heterocyclyl with a suitable alpha-halo ketone in the presence of a solvent, such as DMF, and a suitable base, such as potassium carbonate.
  • a solvent such as DMF
  • a suitable base such as potassium carbonate
  • intermediates of formula (II) containing carboxylic ester groups i.e. C0 2 C 1 . 6 alkyl (such as C0 2 CH 3 , C0 2 CH 2 CH 3 and C0 2 CH 2 CH 2 CH 3 ) may be converted to their corresponding carboxylic acids using various conditions (e.g. treatment with aq. NaOH in methanol/THF) which may then be coupled with any suitable primary or secondary amides using a variety of standard peptide coupling techniques to make the corresponding amides (e.g. the use of a peptide coupling agent such as HATU, HBTU, EDCI etc. with the appropriate solvent and base).
  • a peptide coupling agent such as HATU, HBTU, EDCI etc.
  • a process for producing a compound of formula (I) when B is -CONH-R7- comprising the step of reacting a compound of formula (II) with an amino precursor of general formula NH 2 R 7 under amide coupling conditions.
  • Suitable amide coupling conditions will be understood by those skilled in the art and have been described in many references such as Advanced Organic Chemistry - 4 th Edition, March J., John Wiley & Sons Inc, New York, 1992 (see also 5 th Edition, John Wiley & Sons, New York 2001 and 6 th Edition, John Wiley & Sons, New Jersey, 2007).
  • compounds of formula (II) have also demonstrated antiviral activity. Accordingly, compounds of formula (II) will be understood to be process intermediates and/or final compounds as the case may be.
  • Preparative HPLC was carried out using either a Gilson 322 pump with a Gilson 215 liquid handler and a HP1 100 PDA detector or an Agilent 1200 Series mass detected preparative LCMS using a Varian XRs C-18 100 x 21 .2 mm column. Unless otherwise specified, the HPLC systems employed Phenomenex C8(2) columns using either acetonitrile or acetonitrile containing 0.06% TFA in water or water containing 0.1 % TFA.
  • BSA Bovine serum albumin
  • DIPEA N,N-Diisopropylethylamine
  • DMEM Dulbecco's modified eagle medium
  • GTP Guanosine triphosphate
  • HATU 2-(7-Aza-1 H-benzotriazole-1 -yl)-1 , 1 ,3,3-tetramethyluronium hexafluorophosphate
  • HBTU 0-(Benzotriazol-1 -yl)-/V,/V,/V',A/-tetramethyluronium hexafluorophosphate
  • LHMDS Lithium hexamethyldisilazide
  • Step a To a solution of 1-(4-fluorophenyl)ethanone (5.00 g; 36.20 mmol) in THF (80 mL) at - 78°C was added a 1 M THF solution of LHMDS in THF (40 mmol). After 30 minutes the cyclohexanone (3.90 g; 40 mmol) in THF (80mL) was added and the reaction mixture was stirred at that temperature for 30 minutes and then quenched upon addition of an aqueous solution of sodium bircarbonate. Ethyl acetate (200 mL) was added and the organic layer was washed with water (2 x 100 mL) then brine (100 mL).
  • Step b To a solution of 1-(4-fluorophenyl)-2-(1 -hydroxycyclohexyl)ethanone (350 mg; 1 .48 mmol) in DCM (4 mL) was added triethylsilane (450 mg; 3.90 mmol) followed by TFA (2 mL) and the reaction mixture was stirred for 16 hours at ambient temperature. The reaction mixture was partitioned between EtOAc (75 mL) and water (100 mL). The aqueous layer was extracted with EtOAc (3 x 60 mL) and the combined organics were washed with brine (75 mL), dried (MgS0 4 ) and concentrated to leave a brown oil (4100 mg).
  • the crude reaction material was purified by automated flash column chromatography (Biotage-SP4) on silica (80g) eluting with EtOAc and hexane to leave 2-cyclohexyl-1 -(4-fluorophenyl)ethanone (2.20 g) as a colourless oil.
  • Step c To a solution of 2-cyclohexyl-1 -(4-fluorophenyl)ethanone (2.50 g; 1 1 .35 mmol) in dioxane/diethyl ether (1 : 1 ; 100 mL) was added bromine (0.64 mL; 12 mmol) and the reaction mixture was stirred at ambient temperature. After 2 hours the reaction mixture was partitioned between EtOAc (125ml) and water (125 ml) and the aqueous layer was separated and extracted with EtOAc (3 x 30 ml). The combined organics were washed with brine (35 mL). dried (MgS0 4 ) and concentrated to leave 2-bromo-2-cyclohexyl-1 -(4- fluorophenyl)ethanone (2.79 g) as a colourless oil.
  • Step d To a solution of methyl 5-amino-1 H-pyrazole-3-carboxylate (75 mg; 0.53 mmol) in DMF (2 mL) was added the 2-bromo-2-cyclohexyl-1-(4-fluorophenyl)ethanone ( 170 mg; 0.58 mmol) followed by potassium carbonate (263 mg; 2.66 mmol) and the reaction mixture was stirred at 75°C. After 2 hours water (25 mL) was added and the aqueous layer was extracted with EtOAc (3 x 30 mL). The combined organics were washed with brine (25 mL), dried (MgS0 4 ) and concentrated to leave a brown oil (89 mg).
  • Step e To a solution of methyl 3-cyclohexyl-2-(4-fluorophenyl)-1 H-imidazo[1 ,2-b]pyrazole-6- carboxylate (i) (3 mg) in MeOH/THF (1 : 1 ; 1 mL) was added a 1 M aqueous solution of lithium hydroxide (0.09 mmol) and the reaction was heated at 60°C for 3 hrs. A 1 M aqueous solution of citric acid (25 ml) was added and the aqueous layer was extracted with EtOAc (3 x 30 mL). The combined organics were washed with brine (25 mL), dried (MgS0 4 ) and concentrated to leave a brown oil (4 mg). Purification by reverse phase LCMS:
  • Step a To a solution of methyl 3-cyclohexyl-2-(4-fluorophenyl)-1 H-imidazo[1 ,2-b]pyrazole-6- carboxylate (i) (10 mg; 0.03 mmol) in DMF (1 mL) was added iodomethane (0.06 mmol) followed by potassium carbonate (29 mg; 0.29 mmol). After 16 hours H 2 0 (25 ml) was added and the aqueous layer was extracted with EtOAc (3 x 30 mL). The combined organics were washed with brine (25 mL), dried (MgS0 4 ) and concentrated to leave a brown oil (12 mg).
  • Step b To a solution of methyl 3-cyclohexyl-2-(4-fluorophenyl)-1 -methyl-imidazo[1 ,2- b]pyrazole-6-carboxylate (iii) (5 mg; 0.01 mmol) in MeOH/THF (1 : 1 ; 2 mL) was added a 1 M aqueous solution of lithium hydroxide (0.1 mmol). The reaction was heated at 60°C for 2 hrs.
  • Step a To a solution of ethyl 5-amino-1 H-pyrazole-4-carboxylate (30 mg; 0.19 mmol) in DMF (2 ml_) was added 2-bromo-2-cyclohexyl-1-(4-fluorophenyl)ethanone (64 mg; 0.21 mmol) followed by potassium carbonate (96 mg; 0.97 mmol) and the reaction was stirred at ambient temperature for 4 hours. H 2 0 (25 ml) was added and the aqueous layer was extracted with EtOAc (3 x 30 ml_) and the combined organics were washed with brine (25 ml_), dried (MgS0 4 ) and concentrated to leave a brown oil (85 mg).
  • Step b To a solution of ethyl 3-cyclohexyl-2-(4-fluorophenyl)-1 H-imidazo[1 ,2-b]pyrazole-7- carboxylate (v) (75 mg; 0.21 mmol) in DMF (5 mL) was added iodomethane (60 mg; 0.42 mmol) followed by potassium carbonate (105 mg; 1 .06 mmol). After 16 hours H 2 0 (25 ml) was added and the aqueous layer was extracted with EtOAc (3 x 30 mL). The combined organics were washed with brine (25 mL), dried (MgS0 4 ) and concentrated to leave a brown oil (65 mg).
  • Step c To a solution of ethyl 3-cyclohexyl-2-(4-fluorophenyl)-1 -methyl-imidazo[1 ,2- b]pyrazole-7-carboxylate (vi) (20 mg; 0.05 mmol) in MeOH/THF (1 :1 ; 2 mL) was added a 1 M aqueous solution of lithium hydroxide (1 .08 mmol). The reaction was heated at 60 °C for 6 hrs. 1 M HCI was added until ⁇ pH 3 and the aqueous layer was extracted with EtOAc (3 x 30 mL). The combined organics were washed with brine (25 mL), dried (MgS0 4 ) and concentrated to leave a brown oil (15 mg). Purification by reverse phase LCMS:
  • Step a A 1 M solution of zinc chloride in diethyl ether (39.5 mL) was added to 140 mL anhydrous ether under an atmosphere of argon at 0°C. To this was added
  • Step b To a solution of 2-cyclohexyl-1-phenylethanone (3470 mg) in dioxane/diethyl ether (1 : 1 , 20 mL) was added at rt bromine (930 ⁇ _) in portions over 40 min (progress monitored by 1 H NMR), and the brown mixture was stirred at ambient temperature for another 30 min. Work-up: the reaction mixture was partitioned between EtOAc (100 ml) and NaHC0 3 (100 ml). The aqueous layer was separated and extracted with EtOAc (100 ml).
  • Step c To a solution of ethyl 5-amino-1 /-/-pyrazole-4-carboxylate (120 mg) in anhydrous DMF (5 mL) was added under an atmosphere of argon 2-bromo-2-cyclohexyl-1 - phenylethanone (185 mg) followed by potassium carbonate (320 mg), and the reaction mixture was stirred at 100 °C for 2 hrs and at rt for 17 hrs. After this period iodomethane (50 pL) was added and the reaction mixture was stirred at rt for 20 min.
  • Step d A solution of ethyl 3-cyclohexyl-1 -methyl-2-phenyl-1 H-imidazo[1 ,2-b]pyrazole-7- carboxylate (ix) (60 mg) in 1 M aquous KOH/1 ,4-dioxane (6.4 mL, 1 : 1 ) was heated at reflux for 2 hrs. The reaction mixture was cooled to 0°C, and adjusted to pH 7 with 1 M HCI and satd NaHC0 3 solution, extracted with EtOAc (2x 20 mL), the combined organic layers were washed with brine (10 mL), dried (MgS0 4 ), filtered and evaporated to drynes to afford an oil that solidified on standing.
  • Step a To a mixture of 63 mL water, 7 mL 7 N NaOH and 60 mL 1 ,2-dichloroethane was added 1 -(2-hydroxyphenyl)ethanone, 1 100 mg tetrabutylammonium bromide and 1 -bromo-2- chloroethane (4.5 mL), and the reaction mixture was stirred vigorously at rt for 96 hrs, then heated at reflux for 16 hrs.
  • Step b To a solution of 1-[2-(2-chloroethoxy)phenyl]ethanone (4200 mg) in THF (90 mL) at - 78 C was added under an atmosphere of argon a 1 M THF solution of LiHMDS (25 mL). After 30 minutes cyclohexanone (2520 ⁇ ) in THF (10 mL) was added and the reaction mixture was stirred at -78 °C for 1 .5 hrs.
  • Step c To a solution of 1-[2-(2-chloroethoxy)phenyl]-2-(1 -hydroxycyclohexyl)ethanone (4910 mg) in anhydrous dichloromethane (100 mL, argon) was added under an atmosphere of argon triethylsilane (27 mL) followed by trifluoroacetic acid (1.5 mL) and the reaction mixture was stirred at ambient temperature for 2.5 days. Progress of the reaction was monitored by TLC. After ca 90% conversion to the product, the reaction mixture was quenched with satd. NaHC0 3 solution (100 mL), followed by extraction with DCM (2x50 mL). The combined organic layers were dried (MgS0 4 ), filtered and evaporated to dryness.
  • Step d To a solution of 1-[2-(2-chloroethoxy)phenyl]-2-cyclohexylethanone (1000 mg) in dioxane/diethyl ether (1 : 1 , 60 mL) was added bromine (180 pL), and the brown mixture was stirred at ambient temperature for 30 min. The progress of the reaction was followed by LCMS. After 30 min reaction time, more bromine (9 pL) was added and stirring was continued for 30 min. The reaction mixture was partitioned between EtOAc (150 ml) and NaHC0 3 (50 ml). The aqueous layer was separated and extracted with EtOAc (50 ml).
  • Step e To a solution of methyl 5-amino-1 H-pyrazole-3-carboxylate hydrochloride (270 mg) in anhydrous DMF (18 mL) under an atmosphere of argon was added sodium hydride (60% in mineral oil, 130 mg) at 0 °C. The reaction mixture was stirred at this temperature for 45 min followed by addition of a solution of 2-bromo-1 -[2-(2-chloroethoxy)phenyl]-2- cyclohexylethanone (500 mg) in anhydrous DMF (18 mL). The reaction mixture was stirred at rt for 21 hrs, followed by heating at 100 °C for 1 hr. The progress of the reaction was monitored by LCMS.
  • Reaction mixture was acidified with glacial acetic acid, concentrated on the rotavap (60 °C), the residue was partitioned between water and EtOAc (200 mL, 1 : 1 ), the aqueous layer was extracted with EtOAc (100 mL), the combined organic layers were dried (MgS0 4 ), filtered and evaporated to dryness to leave a brown oil.
  • Step f A solution of methyl 13-cyclohexyl-6,7-dihydropyrazolo[5',1':2,3]imidazo[1,5- c][1,4]benzoxazepine-10-carboxylate (xi) (40 mg) in 1M aquous KOH/1 ,4-dioxane (6 mL, 1:1) was heated at reflux for 15 min. Reaction mixture was cooled to 0°C, and adjusted to pH 5 with 1 M HCI, then extracted with EtOAc (2x 20 mL), the combined organic layers were washed with brine (10 mL), dried (MgS0 4 ), filtered and evaporated to dryness: 31.3 mg (81 % yield) oil.
  • Step a Resorcinol (2370 mg) and boron trifluoride etherate (4.50 mL) were combined in a RBF under an atmosphere of argon (suspension) and stirred at rt. Cyclohexylacetyl chloride (3.00 mL) was added over a period of 30 min and the reaction mixture was stirred at rt o/n. The reaction mixture was added dropwise to 200 mL 10% aqueous NaOAc solution, stirred at rt for 30 min, then extracted into ether (2x100 mL). The combined organic layers were dried (MgS0 4 ), filtered and evaporated to dryness.
  • Step b To a solution of 2-cyclohexyl-1-(2,4-dihydroxyphenyl)ethanone in anhydrous acetonitrile (100 mL) was added under an atmosphere of argon potassium carbonate (4.20 g) and benzyl bromide ( 2.40 mL) and the reaction mixture was stirred at rt for 17 hrs. After this period diethyl ether (300 mL) was added and the mixture was filtered. The filter cake was washed with diethyl ether, and the filtrate was evaporated to dryness to afford 6.15 g of a colourless solid.
  • Step c To a solution of 1-[4-(benzyloxy)-2-hydroxyphenyl]-2-cyclohexylethanone (3000 mg) in 1 ,2-dichloroethane (70 mL) was added 1-bromo-2-chloroethane (1200 ⁇ ),
  • Step d To a solution of 1-[4-(benzyloxy)-2-(2-chloroethoxy)phenyl]-2-cyclohexylethanone (2850 mg) in dioxane/diethyl ether (1 : 1 , 160 mL) was added bromine (450 ⁇ ) dropwise within 2 min, and the mixture was stirred at ambient temperature. The reaction was monitored by LCMS. More bromine (2 x 10 ⁇ ) was added in 10 min intervals to reach complete conversion of 1-[4-(benzyloxy)-2-(2-chloroethoxy)phenyl]-2-cyclohexylethanone.
  • Step e To a solution of methyl 5-amino-1 A7-pyrazole-3-carboxylate hydrochloride (350 mg) in anhydrous DMF (15 ml_) was added under an atmosphere of argon sodium hydride (60% in mineral oil, 175 mg) at 0 °C. The reaction mixture was stirred at this temperature for 20 min followed by addition of a solution of 1-[4-(benzyloxy)-2-(2-chloroethoxy)phenyl]-2-bromo- 2-cyclohexylethanone (810 mg) in anhydrous DMF (30 ml_). The progress of the reaction was monitored by LCMS.
  • reaction mixture was stirred at rt for 17 hrs, then heated at 100 °C for 1 hr. After this period the reaction mixture was cooled to rt, acidified with glacial acetic acid and concentrated on the rotavap (60 °C). The residue was partitioned between water and EtOAc (100 ml_, 1 : 1 ), the aqueous layer was extracted with EtOAc (50 mL), the combined organic layers were washed with brine (20 mL), dried (MgS0 4 ), filtered and evaporated to dryness to leave a brown oil.
  • Step f To a solution of methyl 3-(benzyloxy)-13-cyclohexyl-6,7- dihydropyrazolo[5',1 ':2,3]imidazo[1 ,5-c/][1 ,4]benzoxazepine-10-carboxylate (xiii) (15 mg) in methanol (12 ml_) was added palladium on carbon (10%, 3 mg) and the mixture was stirred under a hydrogen atmosphere (4 L gasbag) for 65 min. Work-up: reaction mixture was flushed with argon and filtered through filter aid (Hiflo medium) with methanol. The filtrate was evaporated to dryness.
  • Step a To a solution of (xiv) (10 mg) in anhydrous DMF (1 mL) was added at 0 °C and under under an atmosphere of argon NaH (1 .3 mg). The mixture was stirred at this temperature for 30 min. A solution of 1-[3-(chloromethyl)-4-(morpholin-4-yl)phenyl]pyrrolidin-
  • Step b A solution of (xviii) (6 mg) in 1 M aqueous KOH/1 ,4-dioxane (3 mL, 1 : 1 ) was heated at 40 °C for 30 min, then stirred at rt for 2 hrs. The reaction mixture was cooled to 0°C, and adjusted to pH 5 with 1 M HCI, and extracted with EtOAc (2x 10 mL). The combined organic layers were washed with brine (5 mL), dried (MgS0 4 ), filtered and evaporated to dryness to afford a solid. The crude material was purified on reverse phase silica by gradient elution (C18; 0-100% acetonitrile/H 2 0) and freeze-dried to afford 2.5 mg (43% yield) 13-cyclohexyl-
  • Step a To a solution of 3-cyclohexyl-2-(4-fluorophenyl)-1 -methyl-imidazo[1 ,2-b]pyrazole-6- carboxylic acid (iv) (5.0 mg; 0.01 mmol) in DMF (1 mL) at ambient temperature was added ethyl (2E)-3-(4- ⁇ [(1 -aminocyclobutyl)carbonyl] amino ⁇ phenyl)prop-2-enoate hydrochloride (0.02 mmol) followed by HATU (16.7 mg; 0.04 mmol) and DIPEA (5.7 mg; 0.04 mmol).
  • Step b To a solution of ethyl (E)-3-[4-[[1-[[3-cyclohexyl-2-(4-fluorophenyl)-1 -methyl- imidazo[1 ,2-b]pyrazole-6-carbonyl]amino]cyclobutanecarbonyl]amino] phenyl]prop-2-enoate (1 ) (4 mg; 0.007 mmol) in MeOH/THF (1 : 1 ; 2 mL) was added a 1 M aqueous solution of lithium hydroxide (0.14 mmol) and the reaction mixture was heated at 60°C for 2 hrs.
  • Step a To a solution of 3-cyclohexyl-2-(4-fluorophenyl)-1 -methyl-imidazo[1 ,2-b]pyrazole-7- carboxylic acid (vii) (3 mg; 0.01 mmol) in DCM (1 mL) was added ethyl (E)-3-[4-[(1- aminocyclobutanecarbonyl)amino]phenyl]prop-2-enoate (3.8 mg; 0.01 mmol) followed by HATU (10 mg; 0.03 mmol) and DIPEA (3.4 mg; 0.03 mmol).
  • Step b To a solution of ethyl (E)-3-[4-[[1-[[3-cyclohexyl-2-(4-fluorophenyl)-1 -methyl- imidazo[1 ,2-b]pyrazole-7-carbonyl]amino]cyclobutanecarbonyl] amino]phenyl]prop-2-enoate (4) (5 mg; 0.01 mmol) in MeOH/THF (1 : 1 ; 2 mL) was added a 1 M aqueous solution of lithium hydroxide (0.16 mmol) and the reaction was heated at 60°C for 3 hrs.
  • Step a To a solution of compound 3-cyclohexyl-1 -methyl-2-phenyl-1 H-imidazo[1 ,2- 6]pyrazole-7-carboxylic acid (x) (10 mg) and ethyl (2E)-3-(4- ⁇ [(1- aminocyclobutyl)carbonyl]amino ⁇ phenyl)prop-2-enoate hydrochloride (15 mg) in dry DMF (500 was added under an atmosphere of argon DIPEA (20 pL) followed by HATU (17.6 mg). The reaction mixture was stirred at rt for 16 hrs. Work-up: EtOAc (15 mL) was added and this mixture was washed with brine (5 mL) and concentrated.
  • Step b A suspension of compound (6) (4.5 mg) in 1 ,4-dioxane/isopropanol/0.6 M aqueous LiOH (0.1 mL/0.1 mL/0.08 mL) was stirred at 60-85 °C for 35 min. Work-up: the reaction mixture was cooled in ice/water, acidified with 1 M HCI and concentrated.
  • Step a To a solution of 13-cyclohexyl-6J-dihydropyrazolo[5',1':2,3]imidazo[1 ,5- c][1,4]benzoxazepine-10-carboxylic acid (xii) (10 mg) and ethyl 1- aminocyclobutanecarboxylate hydrochloride (5.7 mg) in dry DMF (2 mL) under an atmosphere of argon was added DIPEA (16 pL) followed by HATU (13 mg). The reaction mixture was stirred at rt for 17 hrs.
  • Step b A solution of compound (8) (9 mg) in 1 M aquous KOH/1 ,4-dioxane (6 mL, 1 : 1 ) was heated at reflux for 15 min, cooled to 0°C, and adjusted to pH 5 with 1 M HCI and evaporated to dryness.
  • Step c To a solution of compound (9) (7 mg) and ethyl (2E)-3-(4-aminophenyl)prop-2- enoate (3.5 mg) in dry DMF (2 mL) under under an atmosphere of argon was added DIPEA (10 pL) followed by HATU (7.5 mg). The reaction mixture was stirred at rt for 20 hrs. Workup: EtOAc (15 mL) was added and the mixture was washed with brine (5 mL), dried (MgS0 4 ), filtered and concentrated.
  • Step d A suspension of 9 mg compound (10) in 1 ,4-dioxane/isopropanol/0.5 M aqueous LiOH (0.4 mL/0.4 mL/0.32 mL) was stirred in a flask under an atmosphere of argon at 65 °C for 60 min. Work-up: reaction mixture was cooled in ice/water, acidified with 1 M HCI (pH 5) and concentrated.
  • Step a To a solution of 3-cyclohexyl-2-(4-fluorophenyl)-1-methyl-imidazo[1,2-b]pyrazole-6- carboxylic acid (iv) (15 mg; 0.04 mmol) in DCM (1 mL) at ambient temperature was added methyl (2S)-2-amino-3-(4-hydroxyphenyl)propanoate hydrochloride (15 mg; 0.07 mmol), HATU (50 mg; 0.13 mmol) and DIPEA (17 mg; 0.13mmol). After 16 hours a saturated aqueous solution of NaHC0 3 (15 ml) was added and the aqueous layer was extracted with EtOAc (3x 15 mL).
  • Step b To a solution of crude methyl (2S)-2-[[3-cyclohexyl-2-(4-fluorophenyl)-1-methyl- imidazo[1,2-b]pyrazole-6-carbonyl]amino]-3-(4-hydroxyphenyl)propanoate (12) (8 mg) in MeOH/THF (1:1; 2 mL) was added a 1M aqueous solution of lithium hydroxide (0.31 mmol) and the reaction was heated at 60°C for 2 hrs.1M HCI ( aq) was added until ⁇ pH3 and the aqueous layer was extracted with EtOAc (3x 15 mL) and the combined organics were washed with brine (15 mL), dried (MgS0 4 ) and concentrated to leave a brown oil (3 mg).
  • Step a To a solution of 3-cyclohexyl-2-(4-fluorophenyl)-1-methyl-imidazo[1 ,2-b]pyrazole-6- carboxylic acid (iv) (15 mg; 0.04 mmol) in DCM (1 mL) was added methyl (2S)-2-amino-3- (1H-indol-3-yl)propanoate hydrochloride (17 mg; 0.07 mmol) followed by HATU (33 mg; 0.09 mmol) and DIPEA (23 mg; 0.18 mmol). After 2 hours a saturated aqueous solution of NaHC0 3 (15 ml) was added and the aqueous layer was extracted with EtOAc (3x15 mL). The combined organics were washed with brine (10 mL), dried (MgS0 4 ) and concentrated to leave a brown oil (17 mg). Purification of a 4 mg portion by reverse phase LCMS:
  • Step b To a solution of crude methyl N- ⁇ [3-cyclohexyl-2-(4-fluorophenyl)-1-methyl-1H- imidazo[1,2-b]pyrazol-6-yl]carbonyl ⁇ -L-tryptophanate (14) (10 mg) in MeOH/THF (1:1; 2mL) was added a 1M aqueous solution of lithium hydroxide (0.37 mmol).
  • the in vitro and in vivo antiviral activity of the compounds of the invention may be determined using the following protocols.
  • HCV polymerase reactions were carried out using a modified method of Howe et ai , Antimicrobial Agents and Chemotherapy 2004 48(12): 4813-4821.
  • Reactions contained 50 nM NS5bA21 , 20 mM Tris-HCI pH 7.5, 5 rtiM MgCI 2 , 5 mM MnCI 2 , 3 mM DTT, 0.05% BSA, 0.2 U/pL RNasin, 10 ⁇ g mL Poly(rC) template, GTP (at Km) and 0.05 pCi/pL 33 P-GTP in a total reaction volume of 50 pL.
  • a genotype 1 b subgenomic replicon cell line based on Blight et al., Science 2000 290: 1972-1974, modified to express a Renilla luciferase reporter gene was used to assess antiviral activity of test compounds.
  • Cell cultures were maintained in a sub-confluent state in DMEM with glutamine, 10% heat-inactivated foetal bovine serum and Geneticin.
  • Table 2 provides EC 50 values for selected carboxylic esters of the invention.
  • Table 2 EC 50 and IC 50 values for selected compounds of the invention
  • Cytotoxicity of compounds against genotype 1 b subgenomic replicon cells were assessed using the MTT assay (Watanabe et al. , Journal of Virological Methods 1994 48:257-265). Plates were prepared as described for the HCV eplicon assay and cytotoxicity of the test article was evaluated after three days. MTT was added to assay plates followed by three hour incubation at 37 ° C. Wells were aspirated to dryness and the formazan dye dissolved by the addition of 100% isopropanol. Absorbencies were read in a spectrophotometer at two wavelengths (540 nm and 690 nm). The compound concentration that reduced cell viability by 50% (CC 50 ) is calculated using non-linear regression.
  • HCV replicon assays and HCV polymerase assays for genotypes 1 b, 1 a, 2a and 3a to determine the cross-genotype HCV activity of a compound are conducted using essentially the same methods as described above.
  • a genotype 1 b (Con 1 ) subgenomic replicon cell line based on Blight et al. , Science 2000 290: 1972-1974, modified to express a Renilla luciferase reporter gene is used to assess synergy of test compounds.
  • Cell cultures were maintained in a sub-confluent state in DMEM with glutamine, 10% heat-inactivated foetal bovine serum (FBS) and G418 (Geneticin®).
  • Results are analysed and levels of synergy assessed via generation of 3D synergy plots using MacSynergyTM II (Prichard, M. N., K. R. Aseltine, and C. Shipman, Jr. 1993. MacSynergy II. Version 1.0. User's manual. University of Michigan, Ann Arbor.).
  • This method is therefore useful in determining synergistic combinations of an inhibitor of the invention and an HCV inhibitor targeting a different viral protein, or with a different mechanism of inhibiting the NS5B polymerase (for example an NS5A inhibitor, a nucleoside or nucleotide NS5B inhibitor or a NS3/4A protease inhibitor)

Abstract

La présente invention concerne des inhibiteurs des polymérases virales de formule (I), de leurs sels, solvats, hydrates, racémates, énantiomères et isomères, en particulier des inhibiteurs des polymérases virales au sein de la famille des Flaviviridae comme le virus de l'hépatite C (VHC), des procédés pour leur préparation et leur utilisation dans le traitement d'infections virales par Flaviviridae comme les infections par le virus de l'hépatite C (VHC).
PCT/AU2012/001091 2011-09-16 2012-09-13 Composés pour le traitement des infections par vhc WO2013036994A1 (fr)

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US9814721B2 (en) 2010-06-03 2017-11-14 Pharmacyclics Llc Use of inhibitors of bruton'S tyrosine kinase (BTK)
US9885086B2 (en) 2014-03-20 2018-02-06 Pharmacyclics Llc Phospholipase C gamma 2 and resistance associated mutations
US10316040B2 (en) 2015-10-16 2019-06-11 Eisai R&D Management Co., Ltd. EP4 antagonists
US10954567B2 (en) 2012-07-24 2021-03-23 Pharmacyclics Llc Mutations associated with resistance to inhibitors of Bruton's Tyrosine Kinase (BTK)
CN113039186A (zh) * 2018-11-02 2021-06-25 艾库里斯有限及两合公司 抗乙型肝炎病毒HBV的脲6,7-二氢-4H-吡唑并[1,5-a]吡嗪活性剂

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US10653696B2 (en) 2010-06-03 2020-05-19 Pharmacyclics Llc Use of inhibitors of bruton's tyrosine kinase (BTK)
US10004746B2 (en) 2010-06-03 2018-06-26 Pharmacyclics Llc Use of inhibitors of Bruton's tyrosine kinase (Btk)
US10016435B2 (en) 2010-06-03 2018-07-10 Pharmacyclics Llc Use of inhibitors of Bruton's tyrosine kinase (Btk)
US9814721B2 (en) 2010-06-03 2017-11-14 Pharmacyclics Llc Use of inhibitors of bruton'S tyrosine kinase (BTK)
US10478439B2 (en) 2010-06-03 2019-11-19 Pharmacyclics Llc Use of inhibitors of bruton's tyrosine kinase (Btk)
US10004745B2 (en) 2010-06-03 2018-06-26 Pharmacyclics Llc Use of inhibitors of Bruton'S tyrosine kinase (Btk)
US10751342B2 (en) 2010-06-03 2020-08-25 Pharmacyclics Llc Use of inhibitors of Bruton's tyrosine kinase (Btk)
US11672803B2 (en) 2010-06-03 2023-06-13 Pharmacyclics Llc Use of inhibitors of Brutons tyrosine kinase (Btk)
US10954567B2 (en) 2012-07-24 2021-03-23 Pharmacyclics Llc Mutations associated with resistance to inhibitors of Bruton's Tyrosine Kinase (BTK)
US9717731B2 (en) 2012-11-02 2017-08-01 Pharmacyclics Llc TEC family kinase inhibitor adjuvant therapy
US9885086B2 (en) 2014-03-20 2018-02-06 Pharmacyclics Llc Phospholipase C gamma 2 and resistance associated mutations
US10316040B2 (en) 2015-10-16 2019-06-11 Eisai R&D Management Co., Ltd. EP4 antagonists
US11434246B2 (en) 2015-10-16 2022-09-06 Eisai R&D Management Co., Ltd. EP4 antagonists
US10941148B2 (en) 2015-10-16 2021-03-09 Eisai R&D Management Co., Ltd. EP4 antagonists
CN113039186A (zh) * 2018-11-02 2021-06-25 艾库里斯有限及两合公司 抗乙型肝炎病毒HBV的脲6,7-二氢-4H-吡唑并[1,5-a]吡嗪活性剂
JP2022512870A (ja) * 2018-11-02 2022-02-07 アイクリス ゲゼルシャフト ミット ベシュレンクテル ハフツング ウント コンパニー コマンディトゲゼルシャフト Ｂ型肝炎ウイルス（ｈｂｖ）に対して活性を有する新規尿素６，７－ジヒドロ－４ｈ－ピラゾロ［１，５－ａ］ピラジン

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