WO2005079799A1 - 4-acyl-piperazines as anti-viral agents - Google Patents

4-acyl-piperazines as anti-viral agents Download PDF

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Publication number
WO2005079799A1
WO2005079799A1 PCT/EP2005/001451 EP2005001451W WO2005079799A1 WO 2005079799 A1 WO2005079799 A1 WO 2005079799A1 EP 2005001451 W EP2005001451 W EP 2005001451W WO 2005079799 A1 WO2005079799 A1 WO 2005079799A1
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Prior art keywords
carbonyl
methoxy
butylphenyl
piperazine
carboxylic acid
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PCT/EP2005/001451
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French (fr)
Inventor
John Andrew Corfield
Pritom Shah
Martin John Slater
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Glaxo Group Limited
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Priority claimed from GB0403267A external-priority patent/GB0403267D0/en
Priority claimed from GB0422995A external-priority patent/GB0422995D0/en
Application filed by Glaxo Group Limited filed Critical Glaxo Group Limited
Publication of WO2005079799A1 publication Critical patent/WO2005079799A1/en

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    • C—CHEMISTRY; METALLURGY
    • C07—ORGANIC CHEMISTRY
    • C07D—HETEROCYCLIC COMPOUNDS
    • C07D241/00—Heterocyclic compounds containing 1,4-diazine or hydrogenated 1,4-diazine rings
    • C07D241/02—Heterocyclic compounds containing 1,4-diazine or hydrogenated 1,4-diazine rings not condensed with other rings
    • C07D241/04—Heterocyclic compounds containing 1,4-diazine or hydrogenated 1,4-diazine rings not condensed with other rings having no double bonds between ring members or between ring members and non-ring members
    • 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
    • C—CHEMISTRY; METALLURGY
    • C07—ORGANIC CHEMISTRY
    • C07D—HETEROCYCLIC COMPOUNDS
    • C07D403/00—Heterocyclic compounds containing two or more hetero rings, having nitrogen atoms as the only ring hetero atoms, not provided for by group C07D401/00
    • C07D403/02—Heterocyclic compounds containing two or more hetero rings, having nitrogen atoms as the only ring hetero atoms, not provided for by group C07D401/00 containing two hetero rings
    • C07D403/04—Heterocyclic compounds containing two or more hetero rings, having nitrogen atoms as the only ring hetero atoms, not provided for by group C07D401/00 containing two hetero rings directly linked by a ring-member-to-ring-member bond
    • C—CHEMISTRY; METALLURGY
    • C07—ORGANIC CHEMISTRY
    • C07D—HETEROCYCLIC COMPOUNDS
    • C07D417/00—Heterocyclic compounds containing two or more hetero rings, at least one ring having nitrogen and sulfur atoms as the only ring hetero atoms, not provided for by group C07D415/00
    • C07D417/02—Heterocyclic compounds containing two or more hetero rings, at least one ring having nitrogen and sulfur atoms as the only ring hetero atoms, not provided for by group C07D415/00 containing two hetero rings
    • C07D417/06—Heterocyclic compounds containing two or more hetero rings, at least one ring having nitrogen and sulfur atoms as the only ring hetero atoms, not provided for by group C07D415/00 containing two hetero rings linked by a carbon chain containing only aliphatic carbon atoms
    • C—CHEMISTRY; METALLURGY
    • C07—ORGANIC CHEMISTRY
    • C07D—HETEROCYCLIC COMPOUNDS
    • C07D417/00—Heterocyclic compounds containing two or more hetero rings, at least one ring having nitrogen and sulfur atoms as the only ring hetero atoms, not provided for by group C07D415/00
    • C07D417/14—Heterocyclic compounds containing two or more hetero rings, at least one ring having nitrogen and sulfur atoms as the only ring hetero atoms, not provided for by group C07D415/00 containing three or more hetero rings

Definitions

  • the present invention relates to novel acyl piperazine derivatives useful as anti-viral agents. Specifically, the present invention involves novel HCV inhibitors.
  • WO99/37304 and WO01/07436 disclose oxoazaheterocyclyl derivatives, especially piperazinone compounds, having Factor Xa and Factor I la inhibitory activity. These derivatives may include certain acyl piperazine derivatives. There is no mention of HCV polymerase inhibitory activity for the disclosed compounds.
  • WO02/08221 discloses diaryl piperazine derivatives having capsaicin antagonistic activity. These derivatives may include certain acyl piperazine derivatives. There is no mention of HCV polymerase inhibitory activity for the disclosed compounds.
  • WO98/20001 discloses thioproline-containing derivatives having farnesyl protein transferase inhibitory activity. These derivatives may include certain acyl piperazine derivatives. There is no mention of HCV polymerase inhibitory activity for the disclosed compounds.
  • WO99/29705 discloses sialyl Lewis X and sialyl Lewis A glycomimetic compounds having utility in the treatment of selectin-mediated disorders. These compounds may include certain acyl piperazine derivatives. There is no mention of HCV polymerase inhibitory activity for the disclosed compounds.
  • HCV infection is responsible for 40-60% of all chronic liver disease and 30% of all liver transplants.
  • Chronic HCV infection accounts for 30% of all cirrhosis, end-stage liver disease, and liver cancer in the U.S. The CDC estimates that the number of deaths due to HCV will minimally increase to 38,000/year by the year 2010.
  • Alpha-interferon (alone or in combination with ribavirin) has been widely used since its approval for treatment of chronic HCV infection.
  • adverse side effects are commonly associated with this treatment: flu- like symptoms, leukopenia, thrombocytopenia, depression from interferon, as well as anemia induced by ribavirin (Lindsay, K.L. (1997) Hepatology 26 (suppl 1 ): 71S-77S).
  • hepatitis C virus HCV
  • NNBH non-B hepatitis
  • flaviviruses e.g. yellow fever virus and Dengue virus types 1-4
  • pestiviruses e.g.
  • HCV bovine viral diarrhea virus, border disease virus, and classic swine fever virus
  • the HCV genome is approximately 9.6 kilobases (kb) with a long, highly conserved, noncapped 5' nontranslated region (NTR) of approximately 340 bases which functions as an internal ribosome entry site (IRES) (Wang CY et al 'An RNA pseudoknot is an essential structural element of the internal ribosome entry site located within the hepatitis C virus 5' noncoding region' RNA- A Publication of the RNA Society. 1(5): 526-537, 1995 Jul.). This element is followed by a region which encodes a single long open reading frame (ORF) encoding a polypeptide of -3000 amino acids comprising both the structural and nonstructural viral proteins.
  • ORF long open reading frame
  • this RNA Upon entry into the cytoplasm of the cell, this RNA is directly translated into a polypeptide of -3000 amino acids comprising both the structural and nonstructural viral proteins.
  • This large polypeptide is subsequently processed into the individual structural and nonstructural proteins by a combination of host and virally-encoded proteinases (Rice, CM. (1996) in B.N. Fields, D.M.Knipe and P.M. Howley (eds) Virology 2 nd Edition, p931- 960; Raven Press, N.Y.).
  • 3' NTR which roughly consists of three regions: an - 40 base region which is poorly conserved among various genotypes, a variable length poly(U)/polypyrimidine tract, and a highly conserved 98 base element also called the "3' X-tail" (Kolykhalov, A. et al (1996) J. Virology 70:3363-3371; Tanaka, T. et al (1995) Biochem Biophys. Res. Commun. 215:744-749; Tanaka, T. et al (1996) J. Virology 70:3307-3312; Yamada, N. et al (1996) Virology 223:255-261).
  • the 3" NTR is predicted to form a stable secondary structure which is essential for HCV growth in chimps and is believed to function in the initiation and regulation of viral RNA replication.
  • the NS5B protein (591 amino acids, 65 kDa) of HCV (Behrens, S.E. et al (1996) EMBO J. 15:12-22), encodes an RNA-dependent RNA polymerase (RdRp) activity and contains canonical motifs present in other RNA viral polymerases.
  • the NS5B protein is fairly well conserved both intra-typically (-95-98% amino acid (aa) identity across 1 b isolates) and inter-typically (-85% aa identity between genotype 1a and 1b isolates).
  • the essentiality of the HCV NS5B RdRp activity for the generation of infectious progeny virions has been formally proven in chimpanzees (A. A. Kolykhalov et al.. (2000) Journal of Virology, 74(4), p.2046-2051).
  • inhibition of NS5B RdRp activity is predicted to cure HCV infection.
  • the present invention involves acyl piperazine compounds represented hereinbelow, pharmaceutical compositions comprising such compounds and use of the compounds in treating viral infection, especially HCV infection.
  • the present invention provides at least one chemical entity chosen from compounds of Formula (I) :
  • A represents hydroxy or -NH 2 ;
  • D represents aryl or heteroaryl
  • E represents hydrogen, straight or branched chain -C ⁇ alkyl, -CO 2 R 1 , -C(O)R 1a , -C(O)NR 2 R 3 , -SO 2 R ⁇ -SO 2 NR 2 R 3 , aryl, arylC ⁇ alkyl, heteroaryl, heteroaryld-salkyl, heterocyclyl or heterocyclyld-salkyl;
  • R 1 is selected from the group consisting of -C h alky!, aryl, aryld-salkyl, heteroaryl, heteroarylCi-salkyl, heterocyclyl or heterocyclylC ⁇ - 3 alkyl;
  • R 1a is selected from the group consisting of -Ci-ealkyl, aryl, aryld-salkyl, heteroaryl, heteroaryld-salkyl, heterocyclyl or heterocyclylC ⁇ - 3 alkyl;
  • R 2 and R 3 are independently selected from hydrogen, -Ci-ealkyl, aryl and heteroaryl; or R 2 and R 3 together with the nitrogen atom to which they are attached form a 5 or 6 membered saturated cyclic group;
  • G represents -Ci-ealkyl, heterocyclylC ⁇ - 3 alkyl, arylC ⁇ - 3 alkyl or heteroarylCi- 3 alkyl;
  • R is selected from straight or branched chain alkyl, aralkyl, aryloxyalkyl, or aryl, then R is other than tetf-butyl.
  • references herein to therapy and/or treatment includes, but is not limited to prevention, retardation, prophylaxis, therapy and cure of the disease. It will further be appreciated that references herein to treatment or prophylaxis of HCV infection includes treatment or prophylaxis of HCV-associated disease such as liver fibrosis, cirrhosis and hepatocellular carcinoma.
  • a method for the treatment of a human or animal subject with viral infection, particularly HCV infection comprises administering to said human or animal subject an effective amount of at least one chemical entity chosen from compounds of Formula (I) and physiologically acceptable salts, solvates or esters thereof.
  • the method involves inhibiting HCV replication.
  • the compounds of the present invention may contain one or more asymmetric carbon atoms and may exist in racemic, diastereoisomeric, and optically active forms. All of these racemic compounds, enantiomers and diastereoisomers are contemplated to be within the scope of the present invention.
  • the following substituent groups provide certain aspects of the present invention in respect of Formula I:
  • A represents hydroxy
  • D represents optionally substituted phenyl; more preferably terf-butylphenyl optionally further substituted; in a further aspect, D represents para-tert-butylphenyl optionally further substituted, such as mete-substituted, by halo, -d-3alkyl or -d- 3 alkoxy, especially bromo, chloro, methyl or methoxy; in a further aspect, D is mete-methoxy-para- terf-butylphenyl (3-methoxy-4-tert-butylphenyl).
  • R 1a is selected from the group consisting of straight or branched chain -d-ealkyl, aryl, aryld- 3 alkyl, heteroaryl, heteroarylC ⁇ - 3 alkyl, heterocyclyl or heterocyclylCi- 3 alkyl; in a further aspect, R 1a is selected from the group consisting of straight or branched chain -Ci-ealkyl, aryl, arylC ⁇ - 3 alkyl, heteroaryl, or heteroarylC ⁇ - 3 alkyl.
  • E represents hydrogen, methyl, Ph, -PhC(O)CH 3 , -C(O)Me, -C(O)Ph, -C(O)-cyclopentyl, -C(O)NHPh, -C(O)NH-2-CIPh, -C(O)NH-3-CIPh, -C(O)NH-2-MeOPh, -C(O)NH-4-MeOPh, -C(O)NH-cyclohexyl, -C(O)NHEt, -C(O)CH 2 NHC(O)CH 3 , -C(O)(CH 2 ) 2 CO 2 H, -C(O)CH 2 CO 2 H, -CO 2 Me, -CO 2 .-Bu, -CO 2 Ph, -CH 2 Ph, -SO 2 Me, -SO 2 Ph, -SO 2 CH 2 Ph, -SO 2 CH 2 SO 2 Me, pyrimidin-2-yl
  • E represents hydrogen, methyl, Ph, -PhC(O)CH 3 , -C(O)Me, -C(O)Ph, -C(O)NHPh, -C(O)NH-3-CIPh, -C(O)NH-4-MeOPh, -C(O)NH-cyclohexyl, -C(O)NHEt, -C(O)CH 2 NHC(O)CH 3 , -C(O)(CH 2 ) 2 CO 2 H, -C(O)CH 2 CO 2 H, -CO 2 Me, -CO 2 .-Bu, -CO 2 Ph, -CH 2 Ph, -SO 2 Me, -SO 2 Ph, -SO 2 CH 2 Ph, -SO 2 CH 2 SO 2 Me, pyrimidin-2-yl, 1 ,3-benzoxazol-2- yl, 1H-benzimidazol-2-yl, 1 ,3-thiazol-2-
  • E represents hydrogen, methyl, -C(O)Me, -C(O)Ph, -C(O)NHPh, -C(O)NHEt, -C(O)(CH 2 ) 2 CO 2 H, -C(O)CH 2 CO 2 H, -CO 2 Me, -CO 2 f-Bu, -CH 2 Ph, -SO 2 Me, -SO 2 Ph, -SO 2 CH 2 Ph, -SO 2 CH 2 SO 2 Me, or pyrimidin-2-yl.
  • G represents -C h alky!, arylalkyl or heteroarylalkyl; in a further aspect, G represents isobutyl, prop-2-enyl, benzyl, 1 ,3-thiazol-4-ylmethyl, or pyridylmethyl; in a further aspect, G represents isobutyl, benzyl, 1 ,3-thiazol-4-ylmethyl, especially isobutyl or 1 ,3-thiazol-4-ylmethyl.
  • alkyl refers to an optionally substituted, linear, branched or cyclic, saturated or unsaturated hydrocarbon group. Where the alkyl hydrocarbon group is cyclic, it will be understood that there will be a minimum of 3 carbon atoms in the group. Where the alkyl hydrocarbon group is unsaturated, it will be understood that there will be a minimum of 2 carbon atoms in the group and that the group may be, for example, an alkenyl or alkynyl group. In one aspect, the group is saturated.
  • alkyl moieties are -Ci-ealkyl, such as -C ⁇ --,alkyl.
  • optional substituents include Ci-ealkyl, halo, -OR 4 , -SR 4 , -C(O)NR 5 R 6 , -C(O)R 7 , -CO 2 H, -CO 2 R 7 , -NR 5 R 6 , -NHC(O)R 7 , -NHCO 2 R 7 , -NHC(O)NR 8 R 9 , -SO 2 NR 8 R 9 , -SO 2 R 7 , nitro, cyano, or oxo.
  • R 4 represents hydrogen, -Ci-ealkyl, arylalkyl, or heteroarylalkyl
  • R 5 and R 6 independently represent hydrogen, -Ci-ealkyl, aryl or heteroaryl; or R 5 and R 6 together with the nitrogen atom to which they are attached form a 5 or 6 membered saturated cyclic group;
  • R 7 represents -Ci-ealkyl, heterocyclyl, heterocyclylCi-ealkyl, aryl, heteroaryl, arylalkyl or heteroarylalkyl;
  • R 8 and R 9 independently represent hydrogen, aryl, heteroaryl, arylalkyl, or heteroarylalkyl; or R 8 and R 9 together with the nitrogen atom to which they are attached form a 5 or 6 membered saturated cyclic group;
  • alkoxy refers to an alkyl ether radical, wherein the term “alkyl” is defined above.
  • alkoxy as used herein include, but are not limited to; methoxy, ethoxy, n-propoxy, i-propoxy and the like.
  • aryl refers to an optionally substituted aromatic group with at least one ring having a conjugated pi-electron system, containing up to two conjugated or fused ring systems.
  • Aryl includes carbocyclic aryl and biaryl groups, all of which may be optionally substituted, for example phenyl, naphthyl or bi-phenyl. In one aspect, “aryl” contains 6-12 carbon atoms. In one aspect, "aryl” moieties are unsubstituted, monosubstituted, disubstituted or trisubstituted phenyl.
  • aryl substituents are selected from the group consisting of Ci-ealkyl, halo, -OR 4 , -C(O)NR 5 R 6 , -C(O)R 7 , -CO 2 H, -CO 2 R 7 , - NR 5 R ⁇ , -NHC(O)R 7 , -NHCO 2 R 7 , -NHC(O)NR 8 R 9 , -SO 2 NR 8 R 9 , -SO 2 R 7 , cyano, oxo, heterocyclyl, heteroaryl, -CF 3 , and nitro.
  • heteroaryl refers to an optionally substituted, 5, 6 or 9 membered, aromatic group comprising one to four heteroatoms selected from N, O and S, with at least one ring having a conjugated pi-electron system, containing up to two conjugated or fused ring systems.
  • heteroaryl moieties are unsubstituted, monosubstituted, disubstituted or trisubstituted pyrimidinyl, pyridyl, pyrazinyl, thiazolyl, benzoxazolyl and benzimidazolyl.
  • heteroaryl substituents are selected from the group consisting of d- ⁇ alkyl, halo, -OR 4 , -C(O)NR 5 R 6 , -C(O)R 7 , -CO 2 H, -CO 2 R 7 , - NR R 6 , -NHC(O)R 7 , -NHCO 2 R 7 , -NHC(O)NR 8 R 9 , -SO 2 NR 8 R 9 , -SO 2 R 7 , cyano, oxo, heterocyclyl, unsubstituted heteroaryl, -CF 3 , and nitro.
  • heterocyclic and “heterocyclyl” refer to an optionally substituted, 5 or 6 membered, saturated or partially saturated, cyclic hydrocarbon group containing 1 or 2 heteroatoms selected from N, optionally substituted by hydrogen, d ⁇ alkyl, -C(O)R 7 , - SO 2 R 7 , unsubstituted aryl, unsubstituted heteroaryl or unsubstituted heterocyclyl; O; and S, optionally substituted by one or two oxygen atoms.
  • Ring carbon atoms may be optionally substituted by d- ⁇ alkyl, oxo, OR 4 , -NR 5 R 6 , C(O)R 7 , or SO 2 R 7 .
  • chemical entities useful in the present invention may be chosen from compounds of Formula (I) selected from the group consisting of:
  • the present invention provides compounds of Formula (I) selected from the group consisting of Examples 1 to 47 hereinafter defined, and salts, solvates and esters, and where appropriate, individual enantiomers thereof.
  • the present invention provides compounds of Formula (I) selected from the group consisting of Examples 1 to 27 hereinafter defined, and salts, solvates and esters, and where appropriate, individual enantiomers thereof.
  • physiologically acceptable salt complexes also covers the physiologically acceptable salts of the compounds of formula (I).
  • suitable physiologically acceptable salts of the compounds of formula (I) include acid salts, for example sodium, potassium, calcium, magnesium and tetraalkylammonium and the like, or mono- or di- basic salts with the appropriate acid for example organic carboxylic acids such as acetic, lactic, tartaric, malic, isethionic, lactobionic and succinic acids; organic sulfonic acids such as methanesulfonic, ethanesulfonic, benzenesulfonic and p-toluenesulfonic acids and inorganic acids such as hydrochloric, sulfuric, phosphoric and sulfamic acids and the like.
  • the present invention also relates to solvates of the compounds of Formula (I), for example hydrates.
  • the present invention also relates to pharmaceutically acceptable esters of the compounds of Formula (I), for example carboxylic acid esters -COOR, in which R is selected from straight or branched chain alkyl, for example n-propyl, n-butyl, alkoxyalkyl
  • any alkyl moiety present in such esters preferably contains 1 to 18 carbon atoms, particularly 1 to 4 carbon atoms. Any aryl moiety present in such esters preferably comprises a phenyl group.
  • the present invention relates to at least one chemical entity chosen from compounds of Formula (I) and pharmaceutically acceptable salts and solvates thereof.
  • A is a protected hydroxy group, for example an alkoxy, benzyloxy or silyloxy, for example tri-(C . alkyl)-silyloxy group
  • D, E and G are as defined above for Formula (I), by deprotection.
  • Suitable protecting groups can be found, but are not restricted to, those found in T W Greene and P G M Wuts 'Protective Groups in Organic Synthesis', 3 rd Ed
  • an appropriate base for example aqueous sodium hydroxide, optionally in a solvent such as methanol, tetrahydrofuran or mixtures thereof.
  • the temperature is in the range 25 to 100°C, more preferably 50 to 100°C.
  • a suitable solvent such as pyridine, lutidine or collidine, preferably in the temperature range 100-170°C.
  • the reaction is carried out in a solvent, for example dichloromethane.
  • the temperature is in the range 0 to 50°C, more preferably 20 to 30°C.
  • a suitable catalyst for example palladium-on- carbon.
  • the reaction is carried out in a solvent, for example ethanol.
  • the temperature is in the range 0 to 50°C.
  • A is allyloxy
  • D, E and G are as defined above for Formula (I)
  • a suitable catalyst for example tetrakis(triphenylphosphine)palladium(0)
  • a suitable proton source for example phenylsilane.
  • the reaction is carried out in a suitable solvent, for example dichloromethane.
  • A is tri(methyl)silyloxy
  • D, E and G are as defined above for Formula (I)
  • a suitable fluoride source for example tetrabutylammonium fluoride.
  • the reaction is carried out in a suitable solvent, for example tetrahydrofuran.
  • Compounds of Formula (I) in which E represents -C(O)NR 2 R 3 may also be prepared by reaction of a compound of Formula (I) in which E represents H with an isocyanate or a p- nitrophenyl carbamate in a suitable solvent such as dichloromethane or dimethylformamide, optionally in the presence of a base, such as triethylamine or DBU.
  • a suitable solvent such as dichloromethane or dimethylformamide
  • Compounds of Formula (I) in which E represents -C(O)R 1a may be prepared by reaction of a compound of Formula (I) in which E represents H, by reaction with a suitable acylating agent, for example E-hal, wherein hal is a halo atom, preferably chloro or bromo, and E is -C(O)R 1a .
  • suitable acylating agents include acyl halides.
  • the reaction is carried out in the presence of a base, such as DBU, in a suitable solvent, such as DMF.
  • Compounds of Formula (I) in which E represents -C(O)R 1a may also be prepared by reaction of a compound of Formula (I) in which E represents H, with a suitable acid, such as R 1a COOH in the presence of a suitable coupling agent, such as HATU.
  • a suitable acid such as R 1a COOH
  • a suitable coupling agent such as HATU
  • the reaction is carried out in the presence of a base, such as DBU, in a suitable solvent, such as DMF.
  • Compounds of Formula (II) in which E represents -C(O)R 1a may be prepared by reaction of a compound of Formula (III) in which A, D, and G are as defined above for Formula (II); by reaction with a suitable acylating agent, for example E-hal, wherein hal is a halo atom, preferably chloro or bromo. Suitable acylating agents include acyl halides.
  • Compounds of Formula (II) in which E represents -C(O)R 1a may also be prepared by reaction of a compound of Formula (III) with a suitable acid, such as R 1a COOH in the presence of a suitable coupling agent, such as HATU.
  • reaction is carried out in the presence of a base, such as DBU in a suitable solvent, such as DMF.
  • a base such as DBU
  • a suitable solvent such as DMF
  • Compounds of Formula (II) in which E represents -SO 2 R 1 may be prepared by reaction with a suitable sulphonyl haiide.
  • the reaction is carried out in a suitable solvent, for example dichloromethane, in the presence of a suitable base, for example triethylamine.
  • Compounds of Formula (II) in which E represents -C(O)NR 2 R 3 may be prepared by reaction of a compound of Formula (III) with an isocyanate or a p-nitrophenyl carbamate.
  • Compounds of Formula (II) in which E represents an aryl, heteroaryl or heterocycle may be prepared by reaction of a compound of Formula (III) with a suitable halo-aryl, halo-heteroaryl or halo-heterocycle, E-hal, in the presence of a base such as potassium carbonate in a suitable solvent such as DMF, or alternatively by using a palladium catalyst such as palladium acetate, a phosphine catalyst and a base.
  • these reactions may be performed at elevated temperature using radiation, for example by carrying out the reaction in an industrial microwave oven.
  • Compounds of Formula (II) in which E represents -CO 2 R 1 may be prepared by reaction of a compound of Formula (III) with a suitable halo-formate derivative, for example R 1 -O-C(O)hal.
  • Compounds of Formula (II) in which E is a substituted alkyl group may be prepared by reaction of a compound of Formula (III) with a suitable alkylating agent, for example E-hal, in the presence of a base such as potassium carbonate in a suitable solvent such as acetone.
  • A, D and G are as defined for Formula (II) above and P is a suitable nitrogen protecting group, by removal of the protecting group P.
  • Optional protecting groups include, but are not restricted to, tert-butoxycarbonyl (Boc) and benzyloxycarbonyl (CBZ). Boc groups may be removed by acid reagents such as trifluoroacetic acid or hydrogen chloride in a suitable solvent such as dioxan. CBZ groups may be removed by hydrogenolysis using a catalyst such as palladium on carbon in a suitable solvent, for example ethanol.
  • Suitable protecting groups can be found, but are not restricted to, those found in T W Greene and P G M Wuts 'Protective Groups in Organic Synthesis', 3 rd Ed (1999), J Wiley and Sons.
  • a and D are as defined for Formula (II) above and P is a nitrogen protecting group, with a base such as potassium bis(trimethylsilyl) amide and a compound of formula
  • G-L wherein G is as defined for Formula (I), and L is a leaving group such as a halo atom, preferably chloro or bromo, or a sulphonate ester such as mesylate or tosylate.
  • a suitable solvent for example tetrahydrofuran, dimethylformamide or mixtures thereof.
  • A is as defined for Formula (II) above and P is a nitrogen protecting group, by reaction with a suitable acylating agent, for example DC(O)-hal, wherein D is as defined for Formula (I) above and hal is a halo atom, preferably chloro or bromo.
  • a suitable acylating agent for example DC(O)-hal
  • D is as defined for Formula (I) above and hal is a halo atom, preferably chloro or bromo.
  • a suitable solvent for example dichloromethane
  • a suitable base for example triethylamine.
  • Compounds of Formula (IV) may also be prepared by reaction of a compound of Formula (VII) wherein A, and G are as defined for Formula (II) above and P is a nitrogen protecting group; by reaction with a suitable acylating agent, for example DC(O)-hal, wherein D is as defined for Formula (I) above and hal is a halo atom, preferably chloro or bromo.
  • a suitable solvent for example dichloromethane
  • a suitable base for example triethylamine.
  • a and G are as defined for Formula (II) above and P and P' are suitable nitrogen protecting groups, by reaction with a suitable reagent to selectively remove the P' group.
  • suitable reagent examples include hydrogenolysis when P' is a CBZ group, with a catalyst such as palladium on carbon, in a suitable solvent such as ethanol.
  • Suitable protecting groups and deprotection conditions can be found, but are not restricted to, those found in T W Greene and P G M Wuts 'Protective Groups in Organic Synthesis', 3 rd Ed (1999), J Wiley and Sons.
  • A is as defined for Formula (II) above and P and P' are suitable nitrogen protecting groups, with a base such as potassium bis(trimethylsilyl) amide and an alkyl haiide G-hal, wherein hal is a halo atom, preferably chloro or bromo.
  • a base such as potassium bis(trimethylsilyl) amide and an alkyl haiide G-hal, wherein hal is a halo atom, preferably chloro or bromo.
  • hal is a halo atom, preferably chloro or bromo.
  • the reaction is carried out in a suitable solvent, for example tetrahydrofuran, dimethylformamide or mixtures thereof.
  • A, D and E are as defined above for Formula (II), by treatment with a base such as potassium bis(trimethylsilyl) amide and and a compound of formula G-L, wherein G is as defined for Formula (I), and L is a leaving group such as a halo atom, preferably chloro or bromo, or a sulphonate ester such as mesylate or tosylate.
  • a base such as potassium bis(trimethylsilyl) amide
  • G-L wherein G is as defined for Formula (I), and L is a leaving group such as a halo atom, preferably chloro or bromo, or a sulphonate ester such as mesylate or tosylate.
  • a suitable solvent for example tetrahydrofuran, dimethylformamide or mixtures thereof.
  • acylating agent for example E-hal, wherein hal is a halo atom, preferably chloro or bromo.
  • Suitable acylating agents include acyl halides.
  • Compounds of Formula (X) in which E represents -SO 2 R 1 may be prepared by reaction with a suitable sulphonyl haiide. Preferably the reaction is carried out in a suitable solvent, for example dichloromethane, in the presence of a suitable base, for example triethylamine.
  • Compounds of Formula (X) in which E represents -C(O)NR 2 R 3 may be prepared by reaction of a compound of Formula (XI) with an isocyanate or a p-nitrophenyl carbamate.
  • Compounds of Formula (X) in which E is represents an aryl, heteroaryl or heterocycle may be prepared by reaction of a compound of Formula (XI) with a suitable halo-aryl, halo-heteroaryl or halo-heterocycle, E-hal, in the presence of a base such as potassium carbonate in a suitable solvent such as DMF, or alternatively by using a palladium catalyst such as palladium acetate, a phosphine catalyst and a base.
  • Compounds of Formula (X) in which E represents -CO 2 R 1 may be prepared by reaction of a compound of Formula (XI) with a suitable halo-formate derivative (R 1 -O-C(O)hal).
  • Compounds of Formula (X) in which E is a substituted alkyl group may be prepared by reaction of a compound of Formula (XI) with a suitable alkylating agent (E-hal) in the presence of a base such as potassium carbonate, in a suitable solvent such as acetone.
  • Compounds of Formula (XI) may be prepared by reaction of a compound of Formula (V) wherein A and D are as defined for Formula (II) above and P is a suitable nitrogen protecting group, by removal of the protecting group P.
  • Optional protecting groups include, but are not restricted to, terf-butoxycarbonyl (Boc) and benzyloxycarbonyl (CBZ).
  • Boc groups may be removed by acid reagents such as trifluoroacetic acid or hydrogen chloride in a suitable solvent such as dioxan.
  • CBZ groups may be removed by hydrogenolysis using a catalyst such as palladium on carbon in a suitable solvent, for example ethanol.
  • Suitable protecting groups can be found, but are not restricted to, those found in T W Greene and P G M Wuts 'Protective Groups in Organic Synthesis', 3 rd Ed (1999), J Wiley and Sons.
  • racemic compounds of Formula (I), (II), (III), (IV), (V), (VI), (VII), (VIII), (IX), (X) and/or (XI) may be optionally resolved into their individual enantiomers. Such resolutions may conveniently be accomplished by standard methods known in the art. For example, a racemic compound of Formula (I), (II), (III), (IV), (V), (VI), (VII), (VIII), (IX), (X) and/or (XI) may be resolved by chiral preparative HPLC.
  • racemic compounds of Formula (I), (II), (III), (IV), (V), (VI), (VII), (VIII), (IX), (X) and/or (XI) may be resolved by standard diastereoisomeric salt formation with a chiral acid or base reagent as appropriate. Such techniques are well established in the art.
  • Esters of compounds of Formula (I) may be prepared by esterification of a compound of Formula (I) using standard literature procedures for esterification.
  • Compounds of Formula (I) in which A is NH 2 may be prepared from a compound of Formula (I) in which A is hydroxy using a coupling agent such as HATU (O-(7- azabenzotriazol-1yl)-N,N,N',N',-tetramethyluronium hexafluorophosphate) and an ammonium salt, such as ammonium acetate, in the presence of a base, such as triethylamine.
  • a coupling agent such as HATU (O-(7- azabenzotriazol-1yl)-N,N,N',N',-tetramethyluronium hexafluorophosphate) and an ammonium salt, such as ammonium acetate, in the presence of a base, such as triethylamine.
  • Benzimidazole (3.47 g, 29.4 mmol) was dissolved in anhydrous THF (100 mL) at 0°C under an atmosphere of nitrogen.
  • To the stirred solution was added dropwise n-butyl lithium (18.5 mL of a 1.6 M solution in hexanes, 29.6 mmol) then SEM-CI (5.2 mL, 29.4 mmol).
  • the mixture was warmed to ambient temperature for 3 hours and then cooled to -78°C.
  • To the stirred solution was added dropwise n-butyl lithium (18.5 mL of a 1.6 M solution in hexanes, 29.6 mmol).
  • Example 10 1 -[(3-Methoxy-4-tert-butylphenyl)carbonyl]-2-(phenylmethyl)-4- [(phenylmethyl)sulfonyl]-piperazine-2-carboxylic acid
  • Example 15 1-[(3-Methoxy-4-tert-butyiphenyl)carbonyl]-2-(phenylmethyJ)-4-(carboxyacetyl)- piperazine-2-carboxylic acid H NMR (de-DMSO, mixture of rotamers): ⁇ 7.40-7:23 (6H, m), 6.86-6.73 (2H, m), 4.41 (0.65H, d), 3.97 (0.35H, d), 3.86-3.75 (4.35H, m), 3.60-3.12 (7H, m), 3.03 (0.65H, d), 2.98 (1 H, d), 2.67 (1 H, t), 1.33 (9H, s).
  • Example 48 1 -[(3-Methoxy-4-tert-butylphenyl)carbonyl]-2-(1 ,3-thiazol-4-ylmethyl)-4- (cyclopentylcarbonyl)-piperazine-2-carboxylic acid
  • Example 36 1 -[(3-Methoxy-4-tert-butylphenyl)carbonyl]-2-(1 ,3-thiazol-4-ylmethyl)-4-(1 ,3-thiazol-2- yl)-piperazine-2-carboxylic acid
  • the organic phase was separated, evaporated and purified by reverse phase HPLC on a C 8 column using a two- solvent gradient elution with (A) water containing formic acid (0.1%) and (B) acetonitrile- water (95:5 v/v) containing formic acid (0.05%) as the eluents, and analysis of the fractions by electrospray mass spectroscopy.
  • the fractions containing the desired product were combined and evaporated. The residue was freeze dried from dioxan to give the title compound as a solid.
  • compositions for use in therapy comprising a compound of formula (I) or a physiologically acceptable salt or solvate thereof in admixture with one or more physiologically acceptable diluents or carriers.
  • the compounds of the present invention can be administered by different routes including intravenous, intraperitoneal, subcutaneous, intramuscular, oral, topical, transdermal, or transmucosal administration.
  • oral administration is preferred.
  • the compounds can be formulated into conventional oral dosage forms such as capsules, tablets and liquid preparations such as syrups, elixirs and concentrated drops.
  • injection parenteral administration
  • the compounds of the invention are formulated in liquid solutions, preferably, in physiologically compatible buffers or solutions, such as saline solution, Hank's solution, or Ringer's solution.
  • the compounds may be formulated in solid form and redissolved or suspended immediately prior to use. Lyophilized forms can also be produced.
  • Systemic administration can also be by transmucosal or transdermal means.
  • penetrants appropriate to the barrier to be permeated are used in the formulation.
  • penetrants are generally known in the art, and include, for example, for transmucosal administration, bile salts and fusidic acid derivatives.
  • detergents may be used to facilitate permeation.
  • Transmucosal administration for example, may be through nasal sprays, rectal suppositories, or vaginal suppositories.
  • the compounds of the invention can be formulated into ointments, salves, gels, or creams, as is generally known in the art, including administration via a patch.
  • the amounts of various compounds to be administered can be determined by standard procedures taking into account factors such as the compound (IC 50 ) potency, (EC 50 ) efficacy, and the biological half-life (of the compound), the age, size and weight of the patient, and the disease or disorder associated with the patient. The importance of these and other factors to be considered are known to those of ordinary skill in the art.
  • Amounts administered also depend on the routes of administration and the degree of oral bioavailability. For example, for compounds with low oral bioavailability, relatively higher doses will have to be administered. Oral administration is a preferred method of administration of the present compounds.
  • the composition is in unit dosage form.
  • a tablet, or capsule may be administered, for nasal application, a metered aerosol dose may be administered, for transdermal application, a topical formulation or patch may be administered and for transmucosal delivery, a buccal patch may be administered.
  • dosing is such that the patient may administer a single dose.
  • Each dosage unit for oral administration contains suitably from 0.01 to 500 mg/Kg, and preferably from 0.1 to 50 mg/Kg, of a compound of Formula (I) or a pharmaceutically acceptable salt thereof, calculated as the free base.
  • the daily dosage for parenteral, nasal, oral inhalation, transmucosal or transdermal routes contains suitably from 0.01 mg to 100 mg/Kg, of a compound of Formula(l).
  • a topical formulation contains suitably 0.01 to 5.0% of a compound of Formula (I).
  • the active ingredient may be administered from 1 to 6 times per day, preferably once, sufficient to exhibit the desired activity, as is readily apparent to one skilled in the art.
  • Composition of Formula (I) and their pharmaceutically acceptable salts which are active when given orally can be formulated as syrups, tablets, capsules and lozenges.
  • a syrup formulation will generally consist of a suspension or solution of the compound or salt in a liquid carrier for example, ethanol, peanut oil, olive oil, glycerine or water with a flavoring or coloring agent.
  • a liquid carrier for example, ethanol, peanut oil, olive oil, glycerine or water with a flavoring or coloring agent.
  • any pharmaceutical carrier routinely used for preparing solid formulations may be used. Examples of such carriers include magnesium stearate, terra alba, talc, gelatin, acacia, stearic acid, starch, lactose and sucrose.
  • composition is in the form of a capsule
  • any routine encapsulation is suitable, for example using the aforementioned carriers in a hard gelatin capsule shell.
  • composition is in the form of a soft gelatin shell capsule
  • any pharmaceutical carrier routinely used for preparing dispersions or suspensions may be considered, for example aqueous gums, celluloses, silicates or oils, and are incorporated in a soft gelatin capsule shell.
  • Typical parenteral compositions consist of a solution or suspension of a compound or salt in a sterile aqueous or non-aqueous carrier optionally containing a parenterally acceptable oil, for example polyethylene glycol, polyvinylpyrrolidone, lecithin, arachis oil or sesame oil.
  • a parenterally acceptable oil for example polyethylene glycol, polyvinylpyrrolidone, lecithin, arachis oil or sesame oil.
  • compositions for inhalation are in the form of a solution, suspension or emulsion that may be administered as a dry powder or in the form of an aerosol using a conventional non-CFC propellant such as 1 ,1 ,1 ,2-tetrafluoroethane or 1 ,1 ,1 ,2,3,3,3- heptafluoropropane.
  • a conventional non-CFC propellant such as 1 ,1 ,1 ,2-tetrafluoroethane or 1 ,1 ,1 ,2,3,3,3- heptafluoropropane.
  • a typical suppository formulation comprises a compound of Formula (I) or a pharmaceutically acceptable salt thereof which is active when administered in this way, with a binding and/or lubricating agent, for example polymeric glycols, gelatins, cocoa- butter or other low melting vegetable waxes or fats or their synthetic analogs.
  • a binding and/or lubricating agent for example polymeric glycols, gelatins, cocoa- butter or other low melting vegetable waxes or fats or their synthetic analogs.
  • Typical dermal and transdermal formulations comprise a conventional aqueous or non- aqueous vehicle, for example a cream, ointment, lotion or paste or are in the form of a medicated plaster, patch or membrane.
  • Reaction Conditions were 0.5 ⁇ M [ 33 P]-GTP (20 Ci/mMol), 1 mM Dithiothreitol, 20 mM MgCI 2 , 5mM MnCI 2 , 20 mM Tris-HCI, pH7.5, 1.6 ⁇ g/mL polyC/0.256 ⁇ M biotinylated oligoG13, 10% glycerol, 0.01 % NP-40, 0.2 u/ ⁇ L RNasin and 50 mM NaCI.
  • HCV RNA Polymerase Recombinant full-length NS5B (Lohmann et al, J. Virol. 71 (11 ), 1997, 8416 'Biochemical properties of hepatitis C virus NS5B RNA-dependent RNA polymerase and identification of amino acid sequence motifs essential for enzymatic activity') expressed in baculovirus and purified to homogeneity) was added to 4 nM final concentration.
  • 5x concentrated assay buffer mix was prepared using 1 M MnCI 2 (0.25 mL), glycerol (2.5mL), 10% NP-40 (0.025 mL) and Water (7.225 mL), Total 10 mL.
  • 2x concentrated enzyme buffer contained 1M-Tris-HCI, pH7.5 (0.4 mL), 5M NaCI (0.2 mL), 1M-MgCI 2 (0.4 mL), glycerol (1 mL), 10% NP-40 (10 ⁇ L), 1 M DTT (20 ⁇ L) and water (7.97 mL), Total 10 mL
  • Substrate Mix was prepared using 5x Concentrated assay Buffer mix (4 ⁇ L), PJ-GTP (10 ⁇ Ci/ ⁇ L, 0.02 ⁇ L), 25 ⁇ M GTP (0.4 ⁇ L), 40 u/ ⁇ L RNasin (0.1 ⁇ L), 20 ⁇ g/mL polyrC/biotinylated-oligorG (1.6 ⁇ L), and Water (3.94 ⁇ L), Total 10 ⁇ L.
  • Enzyme Mix was prepared by adding 1mg/ml full-length NS5B polymerase (1.5 ⁇ L) to 2.81 mL 2x-concentrated enzyme buffer.
  • the Assay was set up using compound (1 ⁇ L), Substrate Mix (10 ⁇ L), and Enzyme Mix
  • the reaction was performed in a U-bottomed, white, 96-well plate.
  • the reaction was mixed on a plate-shaker, after addition of the Enzyme, and incubated for 1h at 22°C.
  • SPA beads in 0.1 M EDTA were incubated with the reaction mixture for 1h at 22°C after which 120 ⁇ L 0.1 M EDTA in PBS was added. The plate was sealed, mixed centrifuged and incorporated radioactivity determined by counting in a Trilux (Wallac) or
  • the compounds of the invention are of potential therapeutic benefit in the treatment and prophylaxis of HCV.
  • Preferred compounds had an IC 50 of ⁇ 5 ⁇ M.
  • compositions according to the invention may also be used in combination with other therapeutic agents, for example immune therapies (eg. Interferon, such as Interferon alfa-2a (Roferon-A; Hoffmann-La Roche), inteferon alpha-2b (Intron-A; Schering-Plough), interferon alfacon-1 (Infergen; Intermune), peginterferon alpha-2b (Peg-lntron; Schering-Plough) or peginterferon alpha-2a (Pegasys; Hoffmann-La Roche)), therapeutic vaccines, antifibrotic agents, anti-inflammatory agents such as corticosteroids or NSAIDs, bronchodilators such as beta-2 adrenergic agonists and xanthines (e.g.
  • Interferon such as Interferon alfa-2a (Roferon-A; Hoffmann-La Roche), inteferon alpha-2b (Intron-A; Schering-Plough), interferon alfacon-1
  • compositions according to the invention may also be used in combination with gene replacement therapy.
  • the invention thus provides, in a further aspect, a combination comprising a compound of formula (I) or a physiologically acceptable salt or solvate thereof together with another therapeutically active agent, especially interferon and/or ribavirin.

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Abstract

Anti-viral agents of Formula (I) wherein: A represents hydroxy or -NH2; D represents aryl or heteroaryl; E represents hydrogen, straight or branched chain C1-6alkyl, -CO2R1, -C(O)R1a, -C(O)NR2R3, -SO2R1, aryl, arylC1-3alkyl, heteroaryl, heteroarylC1-3alkyl, heterocyclyl or heterocyclylC1-3alkyl; R1 is selected from the group consisting of C1-6alkyl, aryl, arylC1-3alkyl, heteroaryl, heteroarylC1-3alkyl, heterocyclyl or heterocyclylC1-3alkyl; R1a is selected from the group consisting of C1-6alkyl, aryl, arylC1-3alkyl, heteroaryl, heteroarylC1-3alkyl, heterocyclyl or heterocyclylC1-3alkyl; R2 and R3 are independently selected from hydrogen, C1-6alkyl, aryl and heteroaryl; or R2 and R3 together with the nitrogen atom to which they are attached form a 5 or 6 membered saturated cyclic group; G represents C1-6alkyl, heterocyclylC1-3alkyl, arylC1-3alkyl or heteroarylC1-3alkyl; and salts, solvates and esters thereof; provided that when A is esterified to form -OR where R is selected from straight or branched chain alkyl, aralkyl, aryloxyalkyl, or aryl, then R is other than tert-butyl; processes for their preparation, pharmaceutical compositions comprising them, and methods of using them in HCV treatment are provided.

Description

4-ACYL-PIPERAZINES AS ANTI-VIRAL AGENTS
FIELD OF THE INVENTION The present invention relates to novel acyl piperazine derivatives useful as anti-viral agents. Specifically, the present invention involves novel HCV inhibitors.
BACKGROUND OF THE INVENTION
WO99/37304 and WO01/07436 disclose oxoazaheterocyclyl derivatives, especially piperazinone compounds, having Factor Xa and Factor I la inhibitory activity. These derivatives may include certain acyl piperazine derivatives. There is no mention of HCV polymerase inhibitory activity for the disclosed compounds.
WO02/08221 discloses diaryl piperazine derivatives having capsaicin antagonistic activity. These derivatives may include certain acyl piperazine derivatives. There is no mention of HCV polymerase inhibitory activity for the disclosed compounds.
WO98/20001 discloses thioproline-containing derivatives having farnesyl protein transferase inhibitory activity. These derivatives may include certain acyl piperazine derivatives. There is no mention of HCV polymerase inhibitory activity for the disclosed compounds.
WO99/29705 discloses sialyl Lewis X and sialyl Lewis A glycomimetic compounds having utility in the treatment of selectin-mediated disorders. These compounds may include certain acyl piperazine derivatives. There is no mention of HCV polymerase inhibitory activity for the disclosed compounds.
Infection with HCV is a major cause of human liver disease throughout the world. In the US, an estimated 4.5 million Americans are chronically infected with HCV. Although only 30% of acute infections are symptomatic, greater than 85% of infected individuals develop chronic, persistent infection. Treatment costs for HCV infection have been estimated at $5.46 billion for the US in 1997. Worldwide over 200 million people are estimated to be infected chronically. HCV infection is responsible for 40-60% of all chronic liver disease and 30% of all liver transplants. Chronic HCV infection accounts for 30% of all cirrhosis, end-stage liver disease, and liver cancer in the U.S. The CDC estimates that the number of deaths due to HCV will minimally increase to 38,000/year by the year 2010.
Due to the high degree of variability in the viral surface antigens, existence of multiple viral genotypes, and demonstrated specificity of immunity, the development of a successful vaccine in the near future is unlikely. Alpha-interferon (alone or in combination with ribavirin) has been widely used since its approval for treatment of chronic HCV infection. However, adverse side effects are commonly associated with this treatment: flu- like symptoms, leukopenia, thrombocytopenia, depression from interferon, as well as anemia induced by ribavirin (Lindsay, K.L. (1997) Hepatology 26 (suppl 1 ): 71S-77S). This therapy remains less effective against infections caused by HCV genotype 1 (which constitutes -75% of all HCV infections in the developed markets) compared to infections caused by the other 5 major HCV genotypes. Unfortunately, only -50-80% of the patients respond to this treatment (measured by a reduction in serum HCV RNA levels and normalization of liver enzymes) and, of those treated, 50-70% relapse within 6 months of cessation of treatment. Recently, with the introduction of pegylated interferon, both initial and sustained response rates have improved substantially, and combination treatment of Peg-IFN with ribavirin constitutes the gold standard for therapy. However, the side effects associated with combination therapy and the impaired response in patients with genotype 1 present opportunities for improvement in the management of this disease.
First identified by molecular cloning in 1989 (Choo, Q-L et al (1989) Science 244:359- 362), hepatitis C virus (HCV) is now widely accepted as the most common causative agent of post-transfusion non A, non-B hepatitis (NANBH) (Kuo, G et al (1989) Science 244:362-364). Due to its genome structure and sequence homology, this virus was assigned as a new genus in the Flaviviridae family. Like the other members of the Flaviviridae, such as flaviviruses (e.g. yellow fever virus and Dengue virus types 1-4) and pestiviruses (e.g. bovine viral diarrhea virus, border disease virus, and classic swine fever virus) (Choo, Q-L et al (1989) Science 244:359-3; Miller, R.H. and R.H. Purcell (1990) Proc. Natl. Acad. Sci. USA 87:2057-2061), HCV is an enveloped virus containing a single strand RNA molecule of positive polarity. The HCV genome is approximately 9.6 kilobases (kb) with a long, highly conserved, noncapped 5' nontranslated region (NTR) of approximately 340 bases which functions as an internal ribosome entry site (IRES) (Wang CY et al 'An RNA pseudoknot is an essential structural element of the internal ribosome entry site located within the hepatitis C virus 5' noncoding region' RNA- A Publication of the RNA Society. 1(5): 526-537, 1995 Jul.). This element is followed by a region which encodes a single long open reading frame (ORF) encoding a polypeptide of -3000 amino acids comprising both the structural and nonstructural viral proteins.
Upon entry into the cytoplasm of the cell, this RNA is directly translated into a polypeptide of -3000 amino acids comprising both the structural and nonstructural viral proteins. This large polypeptide is subsequently processed into the individual structural and nonstructural proteins by a combination of host and virally-encoded proteinases (Rice, CM. (1996) in B.N. Fields, D.M.Knipe and P.M. Howley (eds) Virology 2nd Edition, p931- 960; Raven Press, N.Y.). Following the termination codon at the end of the long ORF, there is a 3' NTR which roughly consists of three regions: an - 40 base region which is poorly conserved among various genotypes, a variable length poly(U)/polypyrimidine tract, and a highly conserved 98 base element also called the "3' X-tail" (Kolykhalov, A. et al (1996) J. Virology 70:3363-3371; Tanaka, T. et al (1995) Biochem Biophys. Res. Commun. 215:744-749; Tanaka, T. et al (1996) J. Virology 70:3307-3312; Yamada, N. et al (1996) Virology 223:255-261). The 3" NTR is predicted to form a stable secondary structure which is essential for HCV growth in chimps and is believed to function in the initiation and regulation of viral RNA replication.
The NS5B protein (591 amino acids, 65 kDa) of HCV (Behrens, S.E. et al (1996) EMBO J. 15:12-22), encodes an RNA-dependent RNA polymerase (RdRp) activity and contains canonical motifs present in other RNA viral polymerases. The NS5B protein is fairly well conserved both intra-typically (-95-98% amino acid (aa) identity across 1 b isolates) and inter-typically (-85% aa identity between genotype 1a and 1b isolates). The essentiality of the HCV NS5B RdRp activity for the generation of infectious progeny virions has been formally proven in chimpanzees (A. A. Kolykhalov et al.. (2000) Journal of Virology, 74(4), p.2046-2051). Thus, inhibition of NS5B RdRp activity (inhibition of RNA replication) is predicted to cure HCV infection.
Based on the foregoing, there exists a significant need to identify synthetic or biological compounds for their ability to inhibit HCV.
SUMMARY OF THE INVENTION
The present invention involves acyl piperazine compounds represented hereinbelow, pharmaceutical compositions comprising such compounds and use of the compounds in treating viral infection, especially HCV infection.
DETAILED DESCRIPTION OF THE INVENTION
The present invention provides at least one chemical entity chosen from compounds of Formula (I) :
Figure imgf000005_0001
wherein:
A represents hydroxy or -NH2;
D represents aryl or heteroaryl;
E represents hydrogen, straight or branched chain -C^alkyl, -CO2R1, -C(O)R1a, -C(O)NR2R3, -SO2R\ -SO2NR2R3, aryl, arylC^alkyl, heteroaryl, heteroaryld-salkyl, heterocyclyl or heterocyclyld-salkyl;
R1 is selected from the group consisting of -Chalky!, aryl, aryld-salkyl, heteroaryl, heteroarylCi-salkyl, heterocyclyl or heterocyclylCι-3alkyl;
R1a is selected from the group consisting of -Ci-ealkyl, aryl, aryld-salkyl, heteroaryl, heteroaryld-salkyl, heterocyclyl or heterocyclylCι-3alkyl;
R2 and R3 are independently selected from hydrogen, -Ci-ealkyl, aryl and heteroaryl; or R2 and R3 together with the nitrogen atom to which they are attached form a 5 or 6 membered saturated cyclic group;
G represents -Ci-ealkyl, heterocyclylCι-3alkyl, arylCι-3alkyl or heteroarylCi-3alkyl;
and salts, solvates and esters thereof; provided that when A is hydroxy esterified to form -OR where R is selected from straight or branched chain alkyl, aralkyl, aryloxyalkyl, or aryl, then R is other than tetf-butyl.
There is provided as a further aspect of the present invention at least one chemical entity chosen from compounds of Formula (I) and physiologically acceptable salts, solvates or esters thereof for use in human or veterinary medical therapy, particularly in the treatment or prophylaxis of viral infection, particularly HCV infection.
It will be appreciated that reference herein to therapy and/or treatment includes, but is not limited to prevention, retardation, prophylaxis, therapy and cure of the disease. It will further be appreciated that references herein to treatment or prophylaxis of HCV infection includes treatment or prophylaxis of HCV-associated disease such as liver fibrosis, cirrhosis and hepatocellular carcinoma.
According to another aspect of the invention, there is provided the use of at least one chemical entity chosen from compounds of Formula (I) and physiologically acceptable salts, solvates or esters thereof in the manufacture of a medicament for the treatment and/or prophylaxis of viral infection, particularly HCV infection.
In a further or alternative aspect there is provided a method for the treatment of a human or animal subject with viral infection, particularly HCV infection, which method comprises administering to said human or animal subject an effective amount of at least one chemical entity chosen from compounds of Formula (I) and physiologically acceptable salts, solvates or esters thereof. In a further aspect, the method involves inhibiting HCV replication.
It will be appreciated that the compounds of the present invention may contain one or more asymmetric carbon atoms and may exist in racemic, diastereoisomeric, and optically active forms. All of these racemic compounds, enantiomers and diastereoisomers are contemplated to be within the scope of the present invention. The following substituent groups provide certain aspects of the present invention in respect of Formula I:
In one aspect, A represents hydroxy.
In one aspect, D represents optionally substituted phenyl; more preferably terf-butylphenyl optionally further substituted; in a further aspect, D represents para-tert-butylphenyl optionally further substituted, such as mete-substituted, by halo, -d-3alkyl or -d-3alkoxy, especially bromo, chloro, methyl or methoxy; in a further aspect, D is mete-methoxy-para- terf-butylphenyl (3-methoxy-4-tert-butylphenyl).
In one aspect, R1a is selected from the group consisting of straight or branched chain -d-ealkyl, aryl, aryld-3alkyl, heteroaryl, heteroarylCι-3alkyl, heterocyclyl or heterocyclylCi- 3alkyl; in a further aspect, R1a is selected from the group consisting of straight or branched chain -Ci-ealkyl, aryl, arylCι-3alkyl, heteroaryl, or heteroarylCι-3alkyl.
In another aspect, E represents hydrogen, methyl, Ph, -PhC(O)CH3, -C(O)Me, -C(O)Ph, -C(O)-cyclopentyl, -C(O)NHPh, -C(O)NH-2-CIPh, -C(O)NH-3-CIPh, -C(O)NH-2-MeOPh, -C(O)NH-4-MeOPh, -C(O)NH-cyclohexyl, -C(O)NHEt, -C(O)CH2NHC(O)CH3, -C(O)(CH2)2CO2H, -C(O)CH2CO2H, -CO2Me, -CO2.-Bu, -CO2Ph, -CH2Ph, -SO2Me, -SO2Ph, -SO2CH2Ph, -SO2CH2SO2Me, pyrimidin-2-yl, 1 ,3-benzoxazol-2-yl, 1 H-benzimidazol-2-yl, 1 ,3-thiazol-2-yl, or pyrazin-2-yl.
In another aspect, E represents hydrogen, methyl, Ph, -PhC(O)CH3, -C(O)Me, -C(O)Ph, -C(O)NHPh, -C(O)NH-3-CIPh, -C(O)NH-4-MeOPh, -C(O)NH-cyclohexyl, -C(O)NHEt, -C(O)CH2NHC(O)CH3, -C(O)(CH2)2CO2H, -C(O)CH2CO2H, -CO2Me, -CO2.-Bu, -CO2Ph, -CH2Ph, -SO2Me, -SO2Ph, -SO2CH2Ph, -SO2CH2SO2Me, pyrimidin-2-yl, 1 ,3-benzoxazol-2- yl, 1H-benzimidazol-2-yl, 1 ,3-thiazol-2-yl, or pyrazin-2-yl.
In a further aspect, E represents hydrogen, methyl, -C(O)Me, -C(O)Ph, -C(O)NHPh, -C(O)NHEt, -C(O)(CH2)2CO2H, -C(O)CH2CO2H, -CO2Me, -CO2f-Bu, -CH2Ph, -SO2Me, -SO2Ph, -SO2CH2Ph, -SO2CH2SO2Me, or pyrimidin-2-yl.
In one aspect, G represents -Chalky!, arylalkyl or heteroarylalkyl; in a further aspect, G represents isobutyl, prop-2-enyl, benzyl, 1 ,3-thiazol-4-ylmethyl, or pyridylmethyl; in a further aspect, G represents isobutyl, benzyl, 1 ,3-thiazol-4-ylmethyl, especially isobutyl or 1 ,3-thiazol-4-ylmethyl.
It is to be understood that the present invention covers all combinations of aspects, suitable, convenient and preferred groups described herein. As used herein unless otherwise specified, "alkyl" refers to an optionally substituted, linear, branched or cyclic, saturated or unsaturated hydrocarbon group. Where the alkyl hydrocarbon group is cyclic, it will be understood that there will be a minimum of 3 carbon atoms in the group. Where the alkyl hydrocarbon group is unsaturated, it will be understood that there will be a minimum of 2 carbon atoms in the group and that the group may be, for example, an alkenyl or alkynyl group. In one aspect, the group is saturated. In one aspect, alkyl moieties are -Ci-ealkyl, such as -Cι--,alkyl. Unless otherwise stated, optional substituents include Ci-ealkyl, halo, -OR4, -SR4, -C(O)NR5R6, -C(O)R7, -CO2H, -CO2R7, -NR5R6, -NHC(O)R7, -NHCO2R7, -NHC(O)NR8R9, -SO2NR8R9, -SO2R7, nitro, cyano, or oxo.
R4 represents hydrogen, -Ci-ealkyl, arylalkyl, or heteroarylalkyl;
R5 and R6 independently represent hydrogen, -Ci-ealkyl, aryl or heteroaryl; or R5 and R6 together with the nitrogen atom to which they are attached form a 5 or 6 membered saturated cyclic group;
R7 represents -Ci-ealkyl, heterocyclyl, heterocyclylCi-ealkyl, aryl, heteroaryl, arylalkyl or heteroarylalkyl;
R8 and R9 independently represent hydrogen,
Figure imgf000008_0001
aryl, heteroaryl, arylalkyl, or heteroarylalkyl; or R8 and R9 together with the nitrogen atom to which they are attached form a 5 or 6 membered saturated cyclic group;
As used herein, "alkoxy" (when used as a group or as part of a group) refers to an alkyl ether radical, wherein the term "alkyl" is defined above. Examples of alkoxy as used herein include, but are not limited to; methoxy, ethoxy, n-propoxy, i-propoxy and the like.
As used herein, "aryl" refers to an optionally substituted aromatic group with at least one ring having a conjugated pi-electron system, containing up to two conjugated or fused ring systems. "Aryl" includes carbocyclic aryl and biaryl groups, all of which may be optionally substituted, for example phenyl, naphthyl or bi-phenyl. In one aspect, "aryl" contains 6-12 carbon atoms. In one aspect, "aryl" moieties are unsubstituted, monosubstituted, disubstituted or trisubstituted phenyl. In one aspect, "aryl" substituents are selected from the group consisting of Ci-ealkyl, halo, -OR4, -C(O)NR5R6, -C(O)R7, -CO2H, -CO2R7, - NR5Rβ, -NHC(O)R7, -NHCO2R7, -NHC(O)NR8R9, -SO2NR8R9, -SO2R7, cyano, oxo, heterocyclyl, heteroaryl, -CF3, and nitro.
As used herein, "heteroaryl" refers to an optionally substituted, 5, 6 or 9 membered, aromatic group comprising one to four heteroatoms selected from N, O and S, with at least one ring having a conjugated pi-electron system, containing up to two conjugated or fused ring systems. In one aspect, "heteroaryl" moieties are unsubstituted, monosubstituted, disubstituted or trisubstituted pyrimidinyl, pyridyl, pyrazinyl, thiazolyl, benzoxazolyl and benzimidazolyl. In one aspect, "heteroaryl" substituents are selected from the group consisting of d-βalkyl, halo, -OR4, -C(O)NR5R6, -C(O)R7, -CO2H, -CO2R7, - NR R6, -NHC(O)R7, -NHCO2R7, -NHC(O)NR8R9, -SO2NR8R9, -SO2R7, cyano, oxo, heterocyclyl, unsubstituted heteroaryl, -CF3, and nitro.
As used herein, "heterocyclic" and "heterocyclyl" refer to an optionally substituted, 5 or 6 membered, saturated or partially saturated, cyclic hydrocarbon group containing 1 or 2 heteroatoms selected from N, optionally substituted by hydrogen, d^alkyl, -C(O)R7, - SO2R7, unsubstituted aryl, unsubstituted heteroaryl or unsubstituted heterocyclyl; O; and S, optionally substituted by one or two oxygen atoms. Ring carbon atoms may be optionally substituted by d-βalkyl, oxo, OR4, -NR5R6 , C(O)R7, or SO2R7.
In one aspect, chemical entities useful in the present invention may be chosen from compounds of Formula (I) selected from the group consisting of:
1-[(3-Methoxy-4-tert-butylphenyl)carbonyl]-2-(2-methylpropyl)-4-(methylsulfonyl)- piperazine-2-carboxylic acid;
1-[(3-Methoxy-4-tert-butylphenyl)carbonyl]-2-(phenylmethyl)-4-(phenylcarbonyl)- piperazine-2-carboxylic acid; 1-[(3-Methoxy-4-tert-butylphenyl)carbonyl]-2-(phenylmethyl)-4-(methylsulfonyl)- piperazine-2-carboxylic acid;
1-[(3-Methoxy-4-te/t-butylphenyl)carbonyl]-2-(phenylmethyl)-4-(phenylsulfonyl)- piperazine-2-carboxylic acid;
1-[(3-Methoxy-4-tert-butylphenyl)carbonyl]-2,4-bis(phenylmethyl)-piperazine-2-carboxylic acid;
1-[(3-Methoxy-4-fert-butylphenyl)carbonyl]-2-(phenylmethyl)-4-[(phenylamino)carbonyl]- piperazine-2-carboxylic acid;
1-[(3-Methoxy-4-tett-butylphenyl)carbonyl]-2-(phenylmethyl)-4-[(ethylamino)carbonyl]- piperazine-2-carboxylic acid; 1-[(3-Methoxy-4-tert-butylphenyl)carbonyl]-2-(phenylmethyl)-piperazine-2,4-dicarboxylic acid, 4-methyl ester;
1-[(3-Methoxy-4-te/Y-butylphenyl)carbonyl]-2-(phenylmethyl)-piperazine-2,4-dicarboxylic acid, 4-terf-butyl ester;
1-[(3-Methoxy-4-tert-butylphenyl)carbonyl]-2-(phenylmethyl)-4-[(phenylmethyl)sulfonyl]- piperazine-2-carboxylic acid;
1-[(3-Methoxy-4-tert-butylphenyl)carbonyl]-2-(phenylmethyl)-piperazine-2-carboxylic acid hydrochloride;
1-[(3-Methoxy-4-tert-butylphenyl)carbonyl]-2-(phenylmethyl)-4-methyl-piperazine-2- carboxylic acid; 1-[(3-Methoxy-4-tett-butylphenyl)carbonyl]-2-(phenylmethyl)-4-(2-pyrimidinyl)-piperazine-
2-carboxylic acid;
1-[(3-Methoxy-4-tert-butylphenyl)carbonyl]-2-(phenylmethyl)-4-(3-carboxypropanoyl)- piperazine-2-carboxylic acid;
1-[(3-Methoxy-4-fet -butylphenyl)carbonyl]-2-(phenylmethyl)-4-(carboxyacetyl)-piperazine-
2-carboxylic acid;
1-[(3-Methoxy-4-fert-butylphenyl)carbonyl]-2-(phenylmethyl)-4-acetyl-piperazine-2- carboxylic acid;
1-[(3-Methoxy-4-tert-butylphenyl)carbonyl]-2-(2-methylpropyl)-4-(phenylsulfonyl)- piperazine-2-carboxylic acid;
1-[(3-Methoxy-4-tett-butylphenyl)carbonyl]-2-(2-methylpropyl)-4-[(phenylmethyl)sulfonyl]- piperazine-2-carboxylic acid; 1 -[(3-Methoxy-4-te/f-butylphenyl)carbonyl]-2-(2-methylpropyl)-4-(carboxyacetyl)- piperazine-2-carboxylic acid;
1-[(3-Methoxy-4-tert-butylphenyl)carbonyl]-2-(2-methylpropyl)-4-(3-carboxypropanoyl)- piperazine-2-carboxylic acid;
1-[(3-Methoxy-4-tert-butylphenyl)carbonyl]-2-(2-methylpropyl)-4-acetyl-piperazine-2- carboxylic acid;
1-[(3-Methoxy-4-tert-butylphenyl)carbonyl]-2-(2-methylpropyl)-4-(phenylcarbonyl)- piperazine-2-carboxylic acid;
1-[(3-Methoxy-4-tetf-butylphenyl)carbonyl]-2-(2-methylpropyl)-4-[(ethylamino)carbonyl]- piperazine-2-carboxylic acid; 1-[(3-Methoxy-4-tert-butylphenyl)carbonyl]-2-(2-methylpropyl)-4-[(phenylamino)carbonyl]- piperazine-2-carboxylic acid;
1-[(3-Methoxy-4-tert-butylphenyl)carbonyl]-2-(1,3-thiazol-4-ylmethyl)-4-(methylsulfonyl)- piperazine-2-carboxylic acid;
1-[(3-Methoxy-4-tert-butylphenyl)carbonyl]-2-(1 ,3-thiazol-4-ylmethyl)-4-acetyl-piperazine- 2-carboxylic acid;
1-[(3-Methoxy-4-terf-butylphenyl)carbonyl]-2-(phenylmethyl)-4-{[(methylsulfonyl)methyl]- sulfonyl}-piperazine-2-carboxylic acid
1-[(3-Methoxy-4-tert-butylphenyl)carbonyl]-2-(1 ,3-thiazol-4-ylmethyl)-4-(phenylcarbonyl)- piperazine-2-carboxylic acid; 1 -[(3-Methoxy-4-tert-butylphenyl)carbonyl]-2-(1 ,3-thiazol-4-ylmethyl)-4-(phenylsulfonyl)- piperazine-2-carboxylic acid;
1 -[(3-Methoxy-4-ter--butylphenyl)carbonyl]-2-(1 ,3-thiazol-4-ylmethyl)-4-(1 ,3-benzoxazol-2- yl)-piperazine-2-carboxylic acid;
1-[(3-Methoxy-4-tert-butylphenyl)carbonyl]-2-(1 ,3-thiazol-4-ylmethyl)-4-phenylpiperazine- 2-carboxylic acid;
1-[(3-Methoxy-4-te/ -butylphenyl)carbonyl]-2-(1 ,3-thiazol-4-ylmethyl)-4-(4-acetylphenyl)- piperazine-2-carboxylic acid
1-[(3-Methoxy-4-te/t-butylphenyl)carbonyl]-2-(1 ,3-thiazol-4-ylmethyl)-4-(N-acetylglycyl)- piperazine-2-carboxylic acid; 1 -[(3-Methoxy-4-fert-butylphenyl)carbonyl]-2-(1 ,3-thiazol-4-ylmethyl)-4-
[(phenyloxy)carbonyl]-piperazine-2-carboxylic acid;
1 -[(3-Methoxy-4-tert-butylphenyl)carbonyl]-2-(1 ,3-thiazol-4-ylmethyl)-4-(1 H-benzimidazol- 2-yl)-piperazine-2-carboxylic acid hydrochloride; 1 -[(3-Methoxy-4-tert-butylphenyl)carbonyl]-2-(1 ,3-thiazol-4-ylmethyl)-4-(1 ,3-thiazol-2-yl)- piperazine-2-carboxylic acid; 1 -[(3-Methoxy-4-tert-butylphenyl)carbonyl]-2-(1 ,3-thiazol-4-ylmethyl)-4- (2-pyrazinyl)- piperazine-2-carboxylic acid;
1-[(3-Methoxy-4-tert-butylphenyl)carbonyl]-2-(1,3-thiazol-4-ylmethyl)-4-
[(phenylamino)carbonyl]-piperazine-2-carboxylic acid;
1-[(3-Methoxy-4-tert-butylphenyl)carbonyl]-2-(1,3-thiazol-4-ylmethyl)-4-{[(3- chlorophenyl)amino]carbonyl}-piperazine-2-carboxylic acid; 1 -[(3-Methoxy-4-terf-butylphenyl)carbonyl]-2-(1 ,3-thiazol-4-ylmethyl)-4-{[(4-
(methoxyphenyl)amino]carbonyl}-piperazine-2-carboxylic acid;
1-[(3-Methoxy-4-terf-butylphenyl)carbonyl]-2-(1,3-thiazol-4-ylmethyl)-4-
[(cyclohexylamino)carbonyl]-piperazine-2-carboxylic acid;
1-[(3-Methoxy-4-te/ -butylphenyl)carbonyl]-2-(1,3-thiazol-4-ylmethyl)-4-{[(2- methoxyphenyl)amino]carbonyl}-piperazine-2-carboxylic acid; 1-[(3-Methoxy-4-tetf- butylphenyl)carbonyl]-2-(1,3-thiazol-4-ylmethyl)-4-{[(2-chlorophenyl)amino]carbonyl}- piperazine-2-carboxylic acid;
1-[(3-Methoxy-4-fert-butylphenyl)carbonyl]-2-(1,3-thiazol-4-ylmethyl)-piperazine-2,4- dicarboxylic acid, 4-terf-butyl ester; 1 -[(3-Methoxy-4-tert-butylphenyl)carbony.]-2-(1 ,3-thiazol-4-ylmethyl)-piperazine-2- carboxylic acid, hydrochloride;
1-[(3-Methoxy-4-fert-butylphenyl)carbonyl]-2-(1,3-thiazol-4-ylmethyl)-4-[Λ/-(tert- butoxycarbonyl)glycyl]-piperazine-2-carboxylic acid;
1-[(3-Methoxy-4-fe/t-butylphenyl)carbonyl]-2-(1 ,3-thiazol-4-ylmethyl)-4-glycyl-piperazine- 2-carboxylic acid hydrochloride;
1-[(3-Methoxy-4-tett-butylphenyl)carbonyl]-2-(1,3-thiazol-4-ylmethyl)-4-
(cyclopentylcarbonyl)-piperazine-2-carboxylic acid;
and salts, solvates and esters, and individual enantiomers thereof where appropriate.
In one aspect, the present invention provides compounds of Formula (I) selected from the group consisting of Examples 1 to 47 hereinafter defined, and salts, solvates and esters, and where appropriate, individual enantiomers thereof. In another aspect, the present invention provides compounds of Formula (I) selected from the group consisting of Examples 1 to 27 hereinafter defined, and salts, solvates and esters, and where appropriate, individual enantiomers thereof.
Also included in the present invention are pharmaceutically acceptable salt complexes. The present invention also covers the physiologically acceptable salts of the compounds of formula (I). Suitable physiologically acceptable salts of the compounds of formula (I) include acid salts, for example sodium, potassium, calcium, magnesium and tetraalkylammonium and the like, or mono- or di- basic salts with the appropriate acid for example organic carboxylic acids such as acetic, lactic, tartaric, malic, isethionic, lactobionic and succinic acids; organic sulfonic acids such as methanesulfonic, ethanesulfonic, benzenesulfonic and p-toluenesulfonic acids and inorganic acids such as hydrochloric, sulfuric, phosphoric and sulfamic acids and the like.
The present invention also relates to solvates of the compounds of Formula (I), for example hydrates.
The present invention also relates to pharmaceutically acceptable esters of the compounds of Formula (I), for example carboxylic acid esters -COOR, in which R is selected from straight or branched chain alkyl, for example n-propyl, n-butyl, alkoxyalkyl
(e.g. methoxymethyl), aralkyl (e.g. benzyl), aryloxyalkyl (e.g. phenoxymethyl), aryl (e.g. phenyl optionally substituted by halogen, -C1-4alkyl or -Cι-4alkoxy or amino); or for example -CH2OC(O)R' or -CH2OCO2R' in which R' is alkyl (e.g. R' is f-butyl). Unless otherwise specified, any alkyl moiety present in such esters preferably contains 1 to 18 carbon atoms, particularly 1 to 4 carbon atoms. Any aryl moiety present in such esters preferably comprises a phenyl group.
In one aspect, the present invention relates to at least one chemical entity chosen from compounds of Formula (I) and pharmaceutically acceptable salts and solvates thereof.
It will further be appreciated that certain compounds of the present invention may exist in different tautomeric forms. All tautomers are contemplated to be within the scope of the present invention.
Compounds of Formula (I) in which A is hydroxy may be prepared from a compound of
Formula (II)
Figure imgf000012_0001
in which A is a protected hydroxy group, for example an alkoxy, benzyloxy or silyloxy, for example tri-(C . alkyl)-silyloxy group, and D, E and G are as defined above for Formula (I), by deprotection. Suitable protecting groups can be found, but are not restricted to, those found in T W Greene and P G M Wuts 'Protective Groups in Organic Synthesis', 3rd Ed
(1999), J Wiley and Sons.
For example when A is methoxy, and D, E and G are as defined above for Formula (I), by treatment with an appropriate base, for example aqueous sodium hydroxide, optionally in a solvent such as methanol, tetrahydrofuran or mixtures thereof. Preferably, the temperature is in the range 25 to 100°C, more preferably 50 to 100°C. Alternatively, when A is methoxy, and D, E and G are as defined above for Formula (I), by treatment with lithium iodide in a suitable solvent such as pyridine, lutidine or collidine, preferably in the temperature range 100-170°C. For example when A is terf-butoxy, and D, E and G are as defined above for Formula (I), by treatment with an appropriate acid, for example trifluoroacetic acid. Suitably, the reaction is carried out in a solvent, for example dichloromethane. Preferably, the temperature is in the range 0 to 50°C, more preferably 20 to 30°C. For example when A is benzyloxy, and D, E and G are as defined above for Formula (I), by hydrogenolysis in the presence of a suitable catalyst for example palladium-on- carbon. Suitably, the reaction is carried out in a solvent, for example ethanol. Preferably, the temperature is in the range 0 to 50°C.
For example when A is allyloxy, and D, E and G are as defined above for Formula (I), by treatment with a suitable catalyst for example tetrakis(triphenylphosphine)palladium(0) and a suitable proton source, for example phenylsilane. The reaction is carried out in a suitable solvent, for example dichloromethane.
For example when A is tri(methyl)silyloxy, and D, E and G are as defined above for Formula (I), by treatment with a suitable fluoride source for example tetrabutylammonium fluoride. The reaction is carried out in a suitable solvent, for example tetrahydrofuran.
Compounds of Formula (I) in which E represents -C(O)NR2R3 may also be prepared by reaction of a compound of Formula (I) in which E represents H with an isocyanate or a p- nitrophenyl carbamate in a suitable solvent such as dichloromethane or dimethylformamide, optionally in the presence of a base, such as triethylamine or DBU.
Compounds of Formula (I) in which E represents -C(O)R1a may be prepared by reaction of a compound of Formula (I) in which E represents H, by reaction with a suitable acylating agent, for example E-hal, wherein hal is a halo atom, preferably chloro or bromo, and E is -C(O)R1a. Suitable acylating agents include acyl halides. Optionally the reaction is carried out in the presence of a base, such as DBU, in a suitable solvent, such as DMF. Compounds of Formula (I) in which E represents -C(O)R1a may also be prepared by reaction of a compound of Formula (I) in which E represents H, with a suitable acid, such as R1aCOOH in the presence of a suitable coupling agent, such as HATU. Optionally the reaction is carried out in the presence of a base, such as DBU, in a suitable solvent, such as DMF.
Compounds of Formula (II) in which E represents -C(O)R1a may be prepared by reaction of a compound of Formula (III)
Figure imgf000014_0001
in which A, D, and G are as defined above for Formula (II); by reaction with a suitable acylating agent, for example E-hal, wherein hal is a halo atom, preferably chloro or bromo. Suitable acylating agents include acyl halides. Compounds of Formula (II) in which E represents -C(O)R1a may also be prepared by reaction of a compound of Formula (III) with a suitable acid, such as R1aCOOH in the presence of a suitable coupling agent, such as HATU. Optionally the reaction is carried out in the presence of a base, such as DBU in a suitable solvent, such as DMF. Compounds of Formula (II) in which E represents -SO2R1 may be prepared by reaction with a suitable sulphonyl haiide. Preferably the reaction is carried out in a suitable solvent, for example dichloromethane, in the presence of a suitable base, for example triethylamine. Compounds of Formula (II) in which E represents -C(O)NR2R3 may be prepared by reaction of a compound of Formula (III) with an isocyanate or a p-nitrophenyl carbamate. Compounds of Formula (II) in which E represents an aryl, heteroaryl or heterocycle may be prepared by reaction of a compound of Formula (III) with a suitable halo-aryl, halo-heteroaryl or halo-heterocycle, E-hal, in the presence of a base such as potassium carbonate in a suitable solvent such as DMF, or alternatively by using a palladium catalyst such as palladium acetate, a phosphine catalyst and a base. Optionally these reactions may be performed at elevated temperature using radiation, for example by carrying out the reaction in an industrial microwave oven. Compounds of Formula (II) in which E represents -CO2R1 may be prepared by reaction of a compound of Formula (III) with a suitable halo-formate derivative, for example R1-O-C(O)hal. Compounds of Formula (II) in which E is a substituted alkyl group may be prepared by reaction of a compound of Formula (III) with a suitable alkylating agent, for example E-hal, in the presence of a base such as potassium carbonate in a suitable solvent such as acetone.
Compounds of Formula (III) may n of a compound of Formula (IV)
Figure imgf000014_0002
wherein A, D and G are as defined for Formula (II) above and P is a suitable nitrogen protecting group, by removal of the protecting group P. Optional protecting groups include, but are not restricted to, tert-butoxycarbonyl (Boc) and benzyloxycarbonyl (CBZ). Boc groups may be removed by acid reagents such as trifluoroacetic acid or hydrogen chloride in a suitable solvent such as dioxan. CBZ groups may be removed by hydrogenolysis using a catalyst such as palladium on carbon in a suitable solvent, for example ethanol. Suitable protecting groups can be found, but are not restricted to, those found in T W Greene and P G M Wuts 'Protective Groups in Organic Synthesis', 3rd Ed (1999), J Wiley and Sons.
Compounds of Formula (IV) may reaction of a compound of Formula (V)
Figure imgf000015_0001
wherein A and D are as defined for Formula (II) above and P is a nitrogen protecting group, with a base such as potassium bis(trimethylsilyl) amide and a compound of formula
G-L, wherein G is as defined for Formula (I), and L is a leaving group such as a halo atom, preferably chloro or bromo, or a sulphonate ester such as mesylate or tosylate. Preferably the reaction is carried out in a suitable solvent, for example tetrahydrofuran, dimethylformamide or mixtures thereof.
Compounds of Formula (V) may be prepared by reaction of a compound of Formula (VI)
Figure imgf000015_0002
wherein A is as defined for Formula (II) above and P is a nitrogen protecting group, by reaction with a suitable acylating agent, for example DC(O)-hal, wherein D is as defined for Formula (I) above and hal is a halo atom, preferably chloro or bromo. Preferably the reaction is carried out in a suitable solvent, for example dichloromethane, in the presence of a suitable base, for example triethylamine. Compounds of Formula (VI) are known in the literature (for example see Bioorganic Medicinal Chemistry Letters (1999) 9, 1121).
Compounds of Formula (IV) may also be prepared by reaction of a compound of Formula (VII)
Figure imgf000016_0001
wherein A, and G are as defined for Formula (II) above and P is a nitrogen protecting group; by reaction with a suitable acylating agent, for example DC(O)-hal, wherein D is as defined for Formula (I) above and hal is a halo atom, preferably chloro or bromo. Preferably the reaction is carried out in a suitable solvent, for example dichloromethane, in the presence of a suitable base, for example triethylamine.
Compounds of Formula (VII) m pound of Formula (VIM)
Figure imgf000016_0002
wherein A and G are as defined for Formula (II) above and P and P' are suitable nitrogen protecting groups, by reaction with a suitable reagent to selectively remove the P' group. Examples include hydrogenolysis when P' is a CBZ group, with a catalyst such as palladium on carbon, in a suitable solvent such as ethanol. Suitable protecting groups and deprotection conditions can be found, but are not restricted to, those found in T W Greene and P G M Wuts 'Protective Groups in Organic Synthesis', 3rd Ed (1999), J Wiley and Sons.
Compounds of Formula (VIII) n of a compound of Formula (IX)
Figure imgf000016_0003
wherein A is as defined for Formula (II) above and P and P' are suitable nitrogen protecting groups, with a base such as potassium bis(trimethylsilyl) amide and an alkyl haiide G-hal, wherein hal is a halo atom, preferably chloro or bromo. Preferably the reaction is carried out in a suitable solvent, for example tetrahydrofuran, dimethylformamide or mixtures thereof.
Compounds of Formula (IX) are known in the literature (for example see Tetrahedron Letters (1989) 30, 5193). Compounds of Formula (I) may al compound of Formula (X)
Figure imgf000017_0001
in which A, D and E are as defined above for Formula (II), by treatment with a base such as potassium bis(trimethylsilyl) amide and and a compound of formula G-L, wherein G is as defined for Formula (I), and L is a leaving group such as a halo atom, preferably chloro or bromo, or a sulphonate ester such as mesylate or tosylate. Preferably the reaction is carried out in a suitable solvent, for example tetrahydrofuran, dimethylformamide or mixtures thereof.
Compounds of Formula (X) in which E represents -C(O)R1a may be prepared by reaction of a compound of Formula (XI)
Figure imgf000017_0002
in which A and D are as defined above for Formula (II); by reaction with a suitable acylating agent, for example E-hal, wherein hal is a halo atom, preferably chloro or bromo. Suitable acylating agents include acyl halides. Compounds of Formula (X) in which E represents -SO2R1 may be prepared by reaction with a suitable sulphonyl haiide. Preferably the reaction is carried out in a suitable solvent, for example dichloromethane, in the presence of a suitable base, for example triethylamine. Compounds of Formula (X) in which E represents -C(O)NR2R3 may be prepared by reaction of a compound of Formula (XI) with an isocyanate or a p-nitrophenyl carbamate. Compounds of Formula (X) in which E is represents an aryl, heteroaryl or heterocycle may be prepared by reaction of a compound of Formula (XI) with a suitable halo-aryl, halo-heteroaryl or halo-heterocycle, E-hal, in the presence of a base such as potassium carbonate in a suitable solvent such as DMF, or alternatively by using a palladium catalyst such as palladium acetate, a phosphine catalyst and a base. Compounds of Formula (X) in which E represents -CO2R1 may be prepared by reaction of a compound of Formula (XI) with a suitable halo-formate derivative (R1-O-C(O)hal). Compounds of Formula (X) in which E is a substituted alkyl group may be prepared by reaction of a compound of Formula (XI) with a suitable alkylating agent (E-hal) in the presence of a base such as potassium carbonate, in a suitable solvent such as acetone. Compounds of Formula (XI) may be prepared by reaction of a compound of Formula (V) wherein A and D are as defined for Formula (II) above and P is a suitable nitrogen protecting group, by removal of the protecting group P. Optional protecting groups include, but are not restricted to, terf-butoxycarbonyl (Boc) and benzyloxycarbonyl (CBZ). Boc groups may be removed by acid reagents such as trifluoroacetic acid or hydrogen chloride in a suitable solvent such as dioxan. CBZ groups may be removed by hydrogenolysis using a catalyst such as palladium on carbon in a suitable solvent, for example ethanol. Suitable protecting groups can be found, but are not restricted to, those found in T W Greene and P G M Wuts 'Protective Groups in Organic Synthesis', 3rd Ed (1999), J Wiley and Sons.
It will be appreciated that racemic compounds of Formula (I), (II), (III), (IV), (V), (VI), (VII), (VIII), (IX), (X) and/or (XI) may be optionally resolved into their individual enantiomers. Such resolutions may conveniently be accomplished by standard methods known in the art. For example, a racemic compound of Formula (I), (II), (III), (IV), (V), (VI), (VII), (VIII), (IX), (X) and/or (XI) may be resolved by chiral preparative HPLC. Alternatively, racemic compounds of Formula (I), (II), (III), (IV), (V), (VI), (VII), (VIII), (IX), (X) and/or (XI) may be resolved by standard diastereoisomeric salt formation with a chiral acid or base reagent as appropriate. Such techniques are well established in the art.
Esters of compounds of Formula (I) may be prepared by esterification of a compound of Formula (I) using standard literature procedures for esterification.
Compounds of Formula (I) in which A is NH2 may be prepared from a compound of Formula (I) in which A is hydroxy using a coupling agent such as HATU (O-(7- azabenzotriazol-1yl)-N,N,N',N',-tetramethyluronium hexafluorophosphate) and an ammonium salt, such as ammonium acetate, in the presence of a base, such as triethylamine.
Compounds of Formula (I), (II), (III), (IV), (VII) or (VIII) in which G contains an unsaturated alkyl group may be converted into a compound of Formula (I), (II), (III), (IV), (VII) or (VIII) respectively, in which G contains a saturated alkyl group, by hydrogenation. For example, when G is isobutenyl, hydrogenating using hydrogen gas in the presence of a suitable catalyst, such as palladium on carbon, in a suitable solvent, such as ethanol
With appropriate manipulation and protection of any chemical functionality, synthesis of compounds of Formula (I) is accomplished by methods analogous to those above and to those described in the Experimental section. Suitable protecting groups can be found, but are not restricted to, those found in T W Greene and P G M Wuts 'Protective Groups in Organic Synthesis', 3rd Ed (1999), J Wiley and Sons. EXAMPLES
Abbreviations CBZ Benzyloxycarbonyl Boc fe/t-Butoxycarbonyl
DMAP 4-Dimethylaminopyridine
THF Tetrahydrofuran
DMF Dimethylformamide
KHMDS Potassium bis(trimethylsilyl)amide
HATU O-(7-Azabenzotriazol-1-yl)-N,N,N',N'-tetramethyluronium- hexafluorophosphate
DBU 1,8-Diazabicyclo[5.4.0]undec-7-ene
SEM 2-(Trimethylsilyl)ethoxymethyl
DCM Dichloromethane
HCI Hydrochloric acid
HPLC High Pressure Liquid Chromatography
EDTA Ethylenediaminetetraacetic acid
For mass spectroscopy, the mode of ionisation was electrospray.
Intermediate 1
Piperazine-1,2,4-tricarboxylic acid, 1 -benzyl ester 2-methyl ester 4-ferf-butyl ester
Figure imgf000019_0001
To a stirred solution of piperazine-1 ,2,4-tricarboxylic acid, 1 -benzyl ester 4-te/f-butyl ester (5.0 g, 13.7 mmol) in acetone (150 mL) was added methyl iodide (8.5 mL, 137 mmol) and potassium carbonate (5.65 g, 41.1 mmol). The resultant mixture was heated at 60°C under an atmosphere of nitrogen for 18 hours. On cooling to room temperature the solvent was evaporated, then the residue was partitioned between ethyl acetate and water. The organic phase was separated and evaporated to a gum, then purified by chromatography on silica gel using cyclohexane-ethyl acetate (6:1 v/v) as eluent. The fractions containing the desired product were combined and evaporated to give the title compound as a solid. MS calcd for (C19H2eN2O6 + H)+: 379. Found: (M+H)+ = 379. Intermediate 2
Piperazine-2,4-dicarboxylic acid, 2-methyl ester 4-terf-butyl ester
Racemic
Figure imgf000020_0001
A solution of Intermediate 1 (1.0 g, 2.64 mmol) in ethanol (15 mL) was added under a nitrogen atmosphere to wetted palladium, 10 wt. % on activated carbon (0.2 g). The reaction mixture was placed under an atmosphere of hydrogen and stirred vigorously for 18 hours. The mixture was filtered through Celite under a nitrogen atmosphere and the filtrate was evaporated to give the title compound as an oil. MS calcd for (CnH20N2O4 + H)+: 245. Found: (M+H)+ = 245.
Intermediate 3
1 -[(3-Methoxy-4-tert-butylphenyl)carbonyl]-piperazine-2,4-dicarboxylic acid, 2- methyl ester 4-fert-butyl ester
Figure imgf000020_0002
To a solution of Intermediate 2 (1.0 g, 4.1 mmol) in anhydrous dichloromethane (40 mL) was added triethylamine (0.82 mL, 5.9 mmol) and 3-methoxy-4-terf-butylbenzoyl chloride* (1.11 g, 4.9 mmol). The resultant mixture was stirred at ambient temperature for 18 hours and washed with water. The organic phase was separated and evaporated to a gum, then purified by chromatography over silica gel using cyclohexane-ethyl acetate (4:1 , 3:1 and then 2:1 v/v) as eluent. The fractions containing the desired product were combined and evaporated to give the title compound as an amorphous solid. MS calcd for (CaHaiN∑Oβ + H)+: 435. Found: (M+H)+ = 435.
* Prepared from 3-methoxy-4-tetf-butylbenzoic acid (J. Org. Chem. (1961) 26, 1732) using thionyl chloride.
Intermediate 4
1-[(3-Methoxy-4-tert-butylphenyl)carbonyl]-2-(phenylmethyl)-piperazine-2,4- dicarboxylic acid, 2-methyl ester 4-tert-butyl ester
Figure imgf000021_0001
To a stirred solution of Intermediate 3 (1.45 g, 3.34 mmol) in anhydrous THF (24 mL) at - 78 °C under nitrogen, was added anhydrous DMF (3.6 mL) followed by a 0.5M solution of KHMDS in toluene (9.9 mL, 5.0 mmol). After 1 hour, benzyl bromide (0.60 mL, 5.0 mmol) was added to the reaction mixture. The stirred solution was maintained at -78°C for 1 hour then slowly warmed to room temperature overnight. The reaction mixture was quenched with saturated sodium bicarbonate solution and extracted twice with ethyl acetate. The combined organics were dried over magnesium sulphate and evaporated to an oil, then purified by chromatography over silica gel using cyclohexane-ethyl acetate (6:1 v/v) as eluent. The fractions containing the desired product were combined and evaporated to give the title compound as an amorphous solid. MS calcd for (C3oH4oN2O6 + H)+: 525. Found: (M+H)+ = 525.
The following compounds were prepared from alkyl halides using a similar procedure to that described for Intermediate 4:
Intermediate 5
1-[(3-Methoxy-4-tert-butylphenyl)carbonyl]-2-(1,3-thiazol-4-ylmethyl)-piperazine-2,4- dicarboxylic acid, 2-methyl ester 4-fert-butyl ester
Intermediate 6
Piperazine-1,2,4-tricarboxylic acid, 1 -benzyl ester 2-methyl ester 4-fert-butyl ester
Intermediate 49
1-[(3-Methoxy-4-tert-butylphenyl)carbonyl]-2-(1,3-thiazol-4-ylmethyl)-piperazine-2,4- dicarboxylic acid, di-tert-butyl ester
Figure imgf000022_0001
Intermediate 7
2-(2-Methylpropyl)-piperazine-2,4-dicarboxylic acid, 2-methyl ester 4-tert-butyl ester
Figure imgf000022_0002
Intermediate 6 (1.81 g, 4.18 mmol) was dissolved in ethanol (100 mL) and added to wetted palladium, 10 wt. % on activated carbon (1 g) under an atmosphere of nitrogen. The mixture was placed under hydrogen at 50 psi and stirred at ambient temperature for 18 hours. The mixture was filtered through Celite under a nitrogen atmosphere and the filtrate was evaporated to give the title compound as an oil. MS calcd for (C15H28N2O4 + H)+: 301. Found: (M+H)+ = 301. Intermediate 8
1-[(3-Methoxy-4-tert-butylphenyl)carbonyl]-2-(2-methylpropyl)-piperazine-2,4- dicarboxylic acid, 2-methyl ester 4-tert-butyl ester
Figure imgf000023_0001
A solution of Intermediate 7 (1.2 g, 4.0 mmol), triethylamine (0.78 mL, 5.6 mmol) and 3- methoxy-4-tert-butylbenzoyl chloride (1.1g, 4.8 mmol) in chloroform (40 mL) was heated at 65°C with stirring for 18 hours. DMAP (50 mg) was added and heating continued for 18 hours. Extra amounts of 3-methoxy-4-terf-butylbenzoyl chloride (1.1g, 4.8 mmol) and triethylamine (1.0 mL, 7.17 mmol) were added and the mixture was heated at 65°C with stirring for another 18 hours. The reaction mixture was cooled to room temperature and washed with saturated sodium bicarbonate solution. The organic phase was separated and evaporated to a gum, then purified by chromatography over silica gel using dichloromethane-ethyl acetate (25:1 v/v) as eluent. The fractions containing the desired product were combined and evaporated to give the title compound as an amorphous solid.
MS calcd for (C27H42N2O6 + H)+: 491. Found: (M+H)+ = 491.
Intermediate 9 1-[(3-Methoxy-4-tert-butylphenyl)carbonyl]-2-(2-methylpropyl)-piperazine-2- carboxylic acid, methyl ester
Figure imgf000023_0002
Intermediate 8 (0.94 g, 1.91 mmol) was stirred in a 4.0 M solution of HCI in dioxan (5 mL) for 2 hours at ambient temperature. The reaction mixture was evaporated to a gum, then partitioned between dichloromethane and sodium bicarbonate solution. The organic phase was separated and evaporated to give the title compound as a gum. MS calcd for (C22H3-,N2O4 + H)+: 391. Found: (M+H)+ = 391.
The following compounds were prepared using a similar procedure to that described for Intermediate 9: Intermediate 10 1-[(3-Methoxy-4-tert-butylphenyl)carbonyl]-2-(1,3-thiazol-4-ylmethyl)-piperazine-2- carboxylic acid, methyl ester hydrochloride Intermediate 11 1-[(3-Methoxy-4-tert-butylphenyl)carbonyl]-2-(phenylmethyl)-piperazine-2- carboxylic acid, methyl ester
Intermediate 38 (also Example 45) 1-[(3-Methoxy-4-tert-butylphenyl)carbonyl]-2-(1,3-thiazol-4-ylmethyl)-piperazine-2- carboxylic acid, hydrochloride
Figure imgf000024_0001
Intermediate 12 1 -[(3-Methoxy-4-tert-butylphenyl)carbonyl]-2-(phenylmethyl)-4-acetyl-piperazine-2- carboxylic acid, methyl ester
Figure imgf000025_0001
To a stirred solution of Intermediate 11 (37.5 mg, 0.088 mmol) in anhydrous dichloromethane (1.5 mL) was added triethylamine (37 μL, 0.27 mmol) and acetyl chloride (9.4 μL, 0.13 mmol). The resultant mixture was stirred for 1.5 hours and washed with saturated sodium bicarbonate solution. The organic phase was separated and evaporated, then purified by chromatography over silica gel using cyclohexane-ethyl acetate (1:2 v/v) as eluent. The fractions containing the desired product were combined and evaporated to give the title compound as a solid. MS calcd for (C27H3 N2O5 + H)+: 467. Found: (M+H)+ = 467.
The following racemic compounds were prepared from the approriate acyl chlorides or sulfonyl chlorides using a similar procedure to that described for Intermediate 12:
Intermediate 13 1 -[(3-Methoxy-4-tert-butylphenyl)carbonyl]-2-(phenylmethyl)-4-(phenylcarbonyl)- piperazine-2-carboxylic acid, methyl ester
Intermediate 14
1-[(3-Methoxy-4-tert-butylphenyl)carbonyl]-2-(phenylmethyl)-4-(methylsulfonyl)- piperazine-2-carboxylic acid, methyl ester
Intermediate 15
1-[(3-Methoxy-4-tert-butylphenyl)carbonyl]-2-(phenylmethyl)-4-(phenylsulfonyl)- piperazine-2-carboxylic acid, methyl ester
Intermediate 16
1-[(3-Methoxy-4-tert-butylphenyl)carbonyl]-2-(phenylmethyl)-piperazine-2,4- dicarboxylic acid, 2,4-dimethyl ester
Intermediate 17
1-[(3-Methoxy-4-tert-butylphenyl)carbonyl]-2-(phenylmethyl)-4- [(phenylmethyl)sulfonyl]-piperazine-2-carboxylic acid, methyl ester
Intermediate 18 1-[(3-Methoxy-4-tert-butylphenyl)carbonyl]-2-(phenylmethyl)-4-[4-(ethoxy)-4- oxobutanoyl]-piperazine-2-carboxylic acid, methyl ester
Intermediate 19
1-[(3-Methoxy-4-tert-butylphenyl)carbonyl]-2-(phenylmethyl)-4-[3-(methoxy)-3- oxopropanoyl]-piperazine-2-carboxylic acid, methyl ester
Intermediate 20
1-[(3-Methoxy-4-tert-butylphenyl)carbonyl]-2-(2-methylpropyl)-4-(methylsulfonyl)- piperazine-2-carboxylic acid, methyl ester
Intermediate 21
1-[(3-Methoxy-4-tert-butylphenyl)carbonyl]-2-(2-methylpropyl)-4-(phenylsulfonyl)- piperazine-2-carboxylic acid, methyl ester
Intermediate 22
1-[(3-Methoxy-4-tert-butylphenyl)carbonyl]-2-(2-methylpropyl)-4- [(phenylmethyl)sulfonyl]-piperazine-2-carboxylic acid, methyl ester
Intermediate 23 1-[(3-Methoxy-4-tert-butylphenyl)carbonyl]-2-(2-methylpropyl)-4-[3-(methoxy)-3- oxopropanoyl]-piperazine-2-carboxylic acid, methyl ester
Intermediate 24
1-[(3-Methoxy-4-tert-butylphenyl)carbonyl]-2-(2-methylpropyl)-4-[4-(methoxy)-4- oxobutanoyl]-piperazine-2-carboxylic acid, methyl ester
Intermediate 25
1-[(3-Methoxy-4-tert-butylphenyl)carbonyl]-2-(2-methylpropyl)-4-acetyl-piperazine-2- carboxylic acid, methyl ester
Intermediate 26
1-[(3-Methoxy-4-tert-butylphenyl)carbonyl]-2-(2-methylpropyl)-4-(phenylcarbonyl)- piperazine-2-carboxylic acid, methyl ester
Intermediate 27
1-[(3-Methoxy-4-tert-butylphenyl)carbonyl]-2-(phenylmethyl)-4- {[(methylsulfonyl)methyl]sulfonyl}-piperazine-2-carboxylic acid, methyl ester
Intermediate 28 1 -[(3-Methoxy-4-tert-butylphenyl)carbonyl]-2-(1 ,3-thiazol-4-ylmethyl)-4- (methylsulfonyl)-piperazine-2-carboxylic acid, methyl ester Intermediate 29
1-[(3-Methoxy-4-tert-butylphenyl)carbonyl]-2-{1,3-thiazol-4-ylmethyl)-4-acetyl- piperazine-2-carboxylic acid, methyl ester
Intermediate 41
1-[(3-Methoxy-4-tert-butylphenyl)carbonyl]-2-{1,3-thiazol-4-ylmethyl)-4- (phenylcarbonyl)-piperazine-2-carboxylic acid, methyl ester
Intermediate 42 1 -[(3-Methoxy-4-tert-butylphenyl)carbonyl]-2-(1 ,3-thiazol-4-ylmethyl)-4- (phenylsulfonyl)-piperazine-2-carboxylic acid, methyl ester
Intermediate 55
1-[(3-Methoxy-4-tert-butylphenyl)carbonyl]-2-(1,3-thiazol-4-ylmethyl)-4- (cyclopentylcarbonyl)-piperazine-2-carboxylic acid, methyl ester
Figure imgf000028_0001
Figure imgf000028_0002
Intermediate 30
1-[(3-Methoxy-4-tert-butylphenyl)carbonyl]-2-(2-methylpropyl)-4- [(ethylamino)carbonyl]-piperazine-2-carboxylic acid, methyl ester
Figure imgf000029_0001
To a stirred solution of Intermediate 9 (40 mg, 0.102 mmol) in anhydrous dichloromethane (2 mL) under a nitrogen atmosphere, was added ethyl isocyanate (11 mg, 0.15 mmol). After 1.5 hours at ambient temperature, the reaction mixture was washed with 2 M hydrochloric acid. The organic phase was separated and evaporated. The residue was purified by chromatography over silica gel using dichloromethane followed by cyclohexane-ethyl acetate (5:1 , 2:1 and then 0:1 v/v) as eluent. The fractions containing the desired product were combined and evaporated to give the title compound as an amorphous solid. MS calcd for (dsHagNaOs + H)+: 462. Found: (M+H)+ = 462.
The following racemic compounds were prepared from the appropriate isocyanates using a similar procedure to that described for Intermediate 30:
Intermediate 31
1-[(3-Methoxy-4-tert-butylphenyl)carbonyl]-2-(2-methylpropyl)-4- [(phenylamino)carbonyl]-piperazine-2-carboxylic acid, methyl ester
Intermediate 32 1 -[(3-Methoxy-4-tert-butylphenyl)carbonyl]-2-(phenylmethyl)-4- [(ethylamino)carbonyl]-piperazine-2-carboxylic acid, methyl ester
Intermediate 33
1-[(3-Methoxy-4-tert-butylphenyl)carbonyl]-2-(phenylmethyl)-4- [(phenylamino)carbonyl]-pipe , methyl ester
Figure imgf000029_0002
Figure imgf000030_0003
Intermediate 34
1-[(3-Methoxy-4-tert-butylphenyl)carbonyl]-2,4-bis(phenylmethyl)-piperazine-2- carboxylic acid, methyl ester
Figure imgf000030_0001
A stirred mixture of Intermediate 11 (50 mg, 0.118 mmol), potassium carbonate (49 mg, 0.354 mmol) and benzyl bromide (28 uL, 0.236 mmol) in acetone (1.5 mL) was heated at 60°C under a nitrogen atmosphere for 2.5 hours. The reaction mixture was partitioned between dichloromethane and water. The organic phase was separated and evaporated, then purified by chromatography over silica gel using cyclohexane, dichloromethane, diethyl ether and then ethyl acetate as eluent. The fractions containing the desired product were combined and evaporated to give the title compound as an amorphous solid. MS calcd for (C32H38N2O4 + H)+: 515. Found: (M+H)+ = 515.
Intermediate 35
1-[(3-Methoxy-4-tert-butylphenyl)carbonyl]-2-(phenylmethyl)-4-methyl-piperazine-2- carboxylic acid, methyl ester
Figure imgf000030_0002
A stirred mixture of Intermediate 11 (80 mg, 0.188 mmol), 37% wt. aqueous formaldehyde (28 uL, 0.376 mmol) and formic acid (28 μL, 0.752 mmol) in methanol (0.5 mL) was heated at 90°C for 18 hours in a sealed Reacti-vial. The solvent was evaporated to give the title compound as an amorphous solid. MS calcd for (d^N^ + H)+: 439. Found: (M+H)+ = 439. i Intermediate 36 1-[(3-Methoxy-4-tert-butylphenyl)carbonyl]-2-(phenylmethyl)-4-(pyrimidin-2-yl)- piperazine-2-carboxylic acid, methyl ester
Figure imgf000031_0001
A stirred mixture of Intermediate 11 (79 mg, 0.186 mmol), 2-bromopyrimidine (35 mg, 0.233 mmol) and potassium carbonate (62 mg, 0.446 mmol) was heated in anhydrous DMF at 140°C for 18 hours. The reaction mixture was cooled to room temperature and partitioned between dichloromethane and water. The organic phase was separated and evaporated, then purified by chromatography over silica gel using cyclohexane-ethyl acetate (3:1 v/v) as eluent. The fractions containing the desired product were combined and evaporated to give the title compound as a solid. MS calcd for (C29H34N4O4 + H)+: 503. Found: (M+H)+ = 503.
Intermediate 37 (also Example 44) 1 -[(3-Methoxy-4-tert-butylphenyl)carbonyl]-2-(1 ,3-thiazol-4-ylmethyl)-piperazine-2,4- dicarboxylic acid, 4-tert-butyl ester
Figure imgf000031_0002
A stirred solution of Intermediate 5 (1.5 g, 2.8 mmol) in THF (20 mL) and methanol (20 mL) was treated with 2 M sodium hydroxide solution (20 mL) and heated at 65°C for 18 hours. The solution was diluted with 2 M hydrochloric acid and extracted twice with ethyl acetate. The combined organic phases were dried over Na2SO4 and evaporated to give the title compound as an amorphous solid. MS calcd for (C^HssNaOeS + H)+: 518. Found: (M+H)+ = 518.
Intermediate 39 (also Example 46)
1-[(3-Methoxy-4-tert-butylphenyl)carbonyl]-2-(1,3-thiazol-4-ylmethyl)^4-[/V-(tert- butoxycarbonyl)glycyl]-pipe
Figure imgf000032_0001
A solution of HATU (160 mg, 0.42 mmol), Boc glycine (61 mg, 0.35 mmol) and DBU (209 uL, 1.4 mmol) in anhydrous DMF (3 mL) was stirred for 10 minutes at ambient temperature. Intermediate 38 (160 mg, 0.35 mmol) was added to the mixture followed by more DBU (105 uL, 0.7 mmol) to make it dissolve and the solution was stirred for 18 hours at ambient temperature. The reaction mixture was evaporated then partitioned between DCM and 1 M hydrochloric acid. The organic phase was separated, washed with saturated NaHCO3 solution and evaportaed to give the title compound as a solid. MS calcd for (C28H38N4O7S + H)+: 575. Found: (M+H)+ = 575.
Intermediate 40 (also Example 47)
1-[(3-Methoxy-4-tert-butylphenyl)carbonyl]-2-(1,3-thiazol-4-ylmethyl)-4-glycyl- piperazine-2-carboxylic acid hydrochloride
Figure imgf000032_0002
Intermediate 39 (217 mg, 0.378 mmol) was stirred in a 4.0 M solution of HCI in dioxan (2 mL) for 2 hours at ambient temperature. The reaction mixture was evaporated to give the title compound as a solid. MS calcd for (C23H3oN4O5S + H)+: 475. Found: (M+H)+ = 475.
Intermediate 43
2-Bromo-1 -[2-(trimethylsilyl)ethoxymethyl]-1 H-benzimidazole
Figure imgf000033_0001
Benzimidazole (3.47 g, 29.4 mmol) was dissolved in anhydrous THF (100 mL) at 0°C under an atmosphere of nitrogen. To the stirred solution was added dropwise n-butyl lithium (18.5 mL of a 1.6 M solution in hexanes, 29.6 mmol) then SEM-CI (5.2 mL, 29.4 mmol). The mixture was warmed to ambient temperature for 3 hours and then cooled to -78°C. To the stirred solution was added dropwise n-butyl lithium (18.5 mL of a 1.6 M solution in hexanes, 29.6 mmol). After 0.5 hours, N-bromosuccinimide (5.3 g, 29.4 mmol) was added in a single portion. The mixture was stirred at -78°C for 1 hour then ambient temperature for 2 hours and quenched by addition of water. The solution was partitioned between ethyl acetate and brine. The organic phase was separated, dried over Na2SO4 and evaporated to an oil. This was purified by chromatography over silica gel eluting with a gradient of 0%-30% ethyl acetate in cyclohexane. The fractions containing the desired product were combined and evaporated to give the title compound as a waxy solid. MS calcd for (Cι3Hι9BrN2OSi + H)+: 327, 329. Found: (M+H)+ = 327, 329.
Intermediate 44
1 -[(3-Methoxy-4-tert-butylphenyl)carbonyl]-2-(1 ,3-thiazol-4-ylmethyl)-4-{1 -[2- (trimethylsilyl)ethoxymethyl]-1H-benzimidazol-2-yl}-piperazine-2-carboxylic acid, methyl ester
Figure imgf000033_0002
Intermediate 10 was partitioned between sodium bicarbonate solution and DCM. The organic phase was separated and evaporated to afford the free base of intermediate 10. A Reacti-vial was charged with the free base of Intermediate 10 (125 mg, 0.29 mmol), Intermediate 43 (111 mg, 0.34 mmol), palladium (II) trifluoroacetate (5 mg, 0.015 mmol), tri-terf-butylphosphine (3 mg, 0.015 mmol), l 3PO4 (72 mg, 0.34 mmol) and anhydrous toluene (0.5 mL). The vessel was sealed under an atmosphere of nitrogen and heated at 120°C for 18 hours. The mixture was partitioned between DCM and water. The organic phase was separated, evaporated and purified by reverse phase HPLC on a Cι8 column using a two-solvent gradient elution with (A) water containing formic acid (0.1%) and (B) acetonitrile-water (95:5 v/v) containing formic acid (0.05%) as the eluents, and analysis of the fractions by electrospray mass spectroscopy. The fractions containing the desired product were combined and evaporated to give the title compound. MS calcd for (C35H47N5O5SSi + H)+: 678. Found: (M+H)+ = 678.
Intermediate 45 1 -[(3-Methoxy-4-tert-butylphenyl)carbonyl]-2-(1 ,3-thiazol-4-ylmethyl)-4-(1 ,3- benzoxazol-2-yl)-piperazine-2-carboxylic acid, methyl ester
Figure imgf000034_0001
A solution of the free base of Intermediate 10 (100 mg, 0.23 mmol) and 2- chlorobenzoxazole (52 mg, 0.34 mmol) in anhydrous DMF (0.75 mL) was treated with diisopropylethylamine (80 uL, 0.46 mmol) by heating at 80 °C for 16 hours. The mixture was evaporated then purified by chromatography over silica gel using cyclohexane-ethyl acetate (3:1 v/v) as eluent. The fractions containing the desired product were combined and evaporated to give the title compound as an amorphous solid. MS calcd for (C^H^OsS + H)+: 549. Found: (M+H)+ = 549.
Intermediate 46 1 -[(3-Methoxy-4-tert-butylphenyl)carbonyl]-2-(1 ,3-thiazol-4-ylmethyl)-4-phenyl- piperazine-2-carboxylic acid, methyl ester
Figure imgf000034_0002
Intermediate 10 was partitioned between sodium bicarbonate solution and DCM. The organic phase was separated and evaporated to afford the free base of intermediate 10. A Reacti-vial was charged with the free base of Intermediate 10 (108 mg, 0.25 mmol), bromobenzene (26 uL, 0.25 mmol), bis(dibenzylideneacetone) palladium (0) (14 mg, 0.025 mmol), tri-terf-butylphosphine (5 mg, 0.025 mmol), sodium terf-butoxide (26 mg, 0.28 mmol) and anhydrous toluene (0.5 mL). The vessel was sealed under an atmosphere of nitrogen and heated at 90°C for 18 hours. The mixture was purified by chromatography over silica gel eluting with cyclohexane, DCM, diethyl ether then ethyl acetate. The fractions containing the desired product were combined and evaporated to give the title compound as an amorphous solid. MS calcd for (C28H33N3O4S + H)+: 508. Found: (M+H)+= 508.
Intermediate 47 1-[(3-Methoxy-4-tert-butylphenyl)carbonyl]-2-(1,3-thiazol-4-ylmethyl)-4-(4- acetylphenyl)-piperazine-2-ca ster
Figure imgf000035_0001
The title compound was prepared from Intermediate 10 and 4-bromoacetophenone using a similar procedure to that described for Intermediate 46. MS calcd for (C3oH35N3O5S + H)+: 550. Found: (M+H)+ = 550.
Intermediate 48
1 -[(3-Methoxy-4-tert-butylphenyl)carbonyl]-piperazine-2,4-dicarboxylic acid, di-tert- butyl ester
Figure imgf000035_0002
The title compound was prepared from piperazine-2,4-dicarboxylic acid, di-terf-butyl ester and 3-methoxy-4-terf-butylbenzoyl chloride using a similar procedure to that described for Intermediate 3. MS calcd for (C26H40N2Oe + H)+: 477. Found: (M+H)+ = 477.
Intermediate 50 1-[(3-Methoxy-4-tert-butylphenyl)carbonyl]-2-(1,3-thiazol-4-ylmethyl)-piperazine-2- carboxylic acid, tert-butyl ester
Figure imgf000036_0001
Intermediate 49 (1.5 g,. 2.6 mmol) was stirred in a 4.0 M solution of HCI in dioxan (5 mL) for 2 hours at ambient temperature. The reaction mixture was evaporated to a gum, then partitioned between ethyl acetate and sodium bicarbonate solution. The organic phase was separated and evaporated to give the title compound as a gum. MS calcd for (C25H35N3O4S+ H)+: 474. Found: (M+H)+ = 474
The following racemic compounds were prepared from the appropriate isocyanates using a similar procedure to that described for Intermediate 30:
Intermediate 51
1-[(3-Methoxy-4-tert-butylphenyl)carbonyl]-2-(1,3-thiazol-4-ylmethyl)-4-{[(3- chlorophenyl)amino]carbonyl}-piperazine-2-carboxylic acid, tert-butyl ester
Intermediate 52
1-[(3-Methoxy-4-tert-butylphenyl)carbonyl]-2-(1,3-thiazol-4-ylmethylH-{[(4- (methoxyphenyl)amino]carbonyl}-piperazine-2-carboxylic acid, tert-butyl ester
Intermediate 53
1-[(3-Methoxy-4-tert-butylphenyl)carbonyl]-2-(1,3-thiazol-4-ylmethyl)-4- [(cyclohexylamino)carbonyi]-piperazine-2-carboxylic acid, tert-butyl ester
Intermediate 54 1 -[(3-Methoxy-4-tert-butylphenyl)carbonyl]-2-(1 ,3-thiazol-4-ylmethyl)-4-{[(2- (methoxyphenyl)amino]carbonyl}-piperazine-2-carboxylic acid, tert-butyl ester
Figure imgf000036_0002
Figure imgf000037_0002
Example 1
1-[(3-Methoxy-4-tert-butylphenyl)carbonyl]-2-(2-methylpropyl)-4-(methylsulfonyl)- piperazine-2-carboxylic acid
Figure imgf000037_0001
A stirred solution of Intermediate 20 (42.2 mg, 0.09 mmol) in THF (1 mL) and methanol (1 mL) was treated with 2 M sodium hydroxide solution (1 mL) and heated at 70°C for 18 hours. The solution was evaporated, then partitioned between dilute hydrochloric acid and dichloromethane. The organic phase was separated and evaporated. Purification was then achieved by reverse phase HPLC on a Cι8 column using a two-solvent gradient elution with (A) water containing formic acid (0.1%) and (B) acetonitrile-water (95:5 v/v) containing formic acid (0.05%) as the eluents, and analysis of the fractions by electrospray mass spectroscopy. The fractions containing the desired product were combined and evaporated. The resultant residue was dissolved in dioxan and freeze-dried to give the title compound as a solid.
MS calcd for (C22H34N2O6S + H)+: 455. Found: (M+H)+ = 455.
1H NMR (CDCI3): δ 7.33 (1H, d), 7.08 (1H, s), 7.01 (1H, d), 3.88 (3H, s), 3.86-3.76 (4H, m), 3.66-3.59 (1H, m), 3.26-3.17 (1H, ), 2.89 (3H, s), 2.34 (1H, dd), 2.03 (1H, dd), 1.88 (1H, m), 1.38 (9H, s), 1.02 (3H, d), 1.00 (3H, d). Carboxylic acid proton is assumed to be exchanged with moisture in the solvent.
The following compounds were prepared using a similar procedure to that described for Example 1 :
Example 2
1-[(3-Methoxy-4-tert-butylphenyl)carbonyl]-2-(phenylmethyl)-4-(phenylcarbonyl)- piperazine-2-carboxylic acid 1H NMR (de-DMSO, 120°C): δ 7.46-7.39 (3H, m), 7.38-7.25 (8H, m), 6.81 (1 H, d), 6.80 (1 H, s), 4.19-4.02 (1 H, m), 3.89 (1H, d), 3.82 (3H, s), 3.77 (1H, d), 3.61-3.44, (2H, m), 3.22-3.12 (2H, m), 3.01 (2H, m), 1.36 (9H, s).
Example 3
1-[(3-Methoxy-4-tert-butylphenyl)carbonyl]-2-(phenylmethyl)-4-(methylsulfonyl)- piperazine-2-carboxylic acid
1 H NMR (CDCI3): δ 7.37-7.28 (6H, m), 6.98 (1 H, s), 6.86 (1H, d), 4.08 (1H, d), 3.93 (1 H, d), 3.87 (3H, s), 3.86 (1 H, d), 3.78 (1H, dt), 3.46-3.32 (2H, m), 3.18-3.08 (1H, m), 3.10 (1H, d), 2.88 (3H, s), 1.38 (9H, s). Carboxylic acid proton is assumed to be exchanged with moisture in the solvent.
Example 4 1 -[(3-Methoxy-4-tert-butylphenyl)carbonyl]-2-(phenylmethyl)-4-(phenylsulfonyl)- piperazine-2-carboxylic acid
1H NMR (CDCI3): δ 7.75 (2H, d), 7.54-7.43 (3H, m), 7.40-7.25 (6H, m), 6.94 (1H, s), 6.76 (1H, d), 3.99 (1 H, d), 3.84 (3H, s), 3.82 (1 H, d), 3.68 (1H, dt), 3.50 (1H, d), 3.45-3.37 (1 H, m), 3.19 (1H, d), 3.16-3.10 (1 H, m), 3.05-2.97 (1H, m), 1.37 (9H, s). Carboxylic acid proton is assumed to be exchanged with moisture in the solvent.
Example 5
1-[(3-Methoxy-4-tert-butylphenyl)carbonyl]-2,4-bis(phenylmethyl)-piperazine-2- carboxylic acid 1H NMR (de-DMSO): δ 7.37-7.26 (7H, m), 7.26-7.16 (4H, m), 6.75 (1 H, d), 6.67 (1H, s), 3.79 (3H, s), 3.68 (1H, d), 3.48 (2H, s), 3.46-3.43 (1H, m), 3.26-3.19 (1H, m), 3.16 (2H, d), 2.73 (1H, d), 2.57 (1H, d), 2.50-2.45 (1H, m), 2.28-2.19 (1 H, m), 1.31 (9H, s).
Example 6 1-[(3-Methoxy-4-tert-butylphenyl)carbonyl]-2-(phenylmethyl)-4- [(phenylamino)carbonyl]-piperazine-2-carboxylic acid
1H NMR (de-DMSO): δ 12.70 (1 H, br s), 8.11(1H, s), 7.45 (2H, d), 7.40-7.34 (2H, m), 7.34- 7.27 (4H, m), 7.22 (2H, t), 6.93 (1 H, t), 6.81 (1H, d), 6.77 (1 H, s), 4.35 (1H, d), 3.85 (1 H, d), 3.84 (3H, s), 3.61-3.51 (2H, m), 3.48-3.41 (1H, m), 3.18 (1H, d), 2.98 (1H, d), 2.74 (1 H, t), 1.34 (9H, s).
Example 7
1-[(3-Methoxy-4-tert-butylphenyl)carbonyl]-2-(phenylmethyl)-4- [(ethylamino)carbonyl]-piperazine-2-carboxylic acid 1H NMR (de-DMSO): δ 12.59 (1 H. br s), 7.38-7.22 (6H, m), 6.78 (1 H, d), 6.73 (1H, s), 6.09 (1H, t), 4.23 (1 H, d), 3.82 (3H, s), 3.81 (1H, d), 3.46 (1 H, d), 3.40-3.25 (2H, m), 3.08-2.90 (4H, m), 2.69 (1H, t), 1.34 (9H, s), 0.98 (3H, t). Example 8 1-[(3-Methoxy-4-tert-butylphenyl)carbonyl]-2-(phenylmethyl)-piperazine-2,4- dicarboxylic acid, 4-methyl ester
Example 9
1-[(3-Methoxy-4-tert-butylphenyl)carbonyl]-2-(phenylmethyl)-piperazine-2,4- dicarboxylic acid, 4-tert-butyl ester 1 H NMR (de-DMSO, mixture of rotamers): δ 12.70 (1 H, br s), 7.38-7.23 (6H, m), 6.80-6.75 (1 H, t), 6.75-6.72 (1H, d), 4.09 (0.5H, d), 3.98 (0.5H, d), 3.82 (3H, s), 3.81-3.76 (1H, m), 3.62-3.55 (0.5H, m), 3.51 (0.5H, d), 3.42-3.27 (3.5H, m), 3.00-2.85 (1H, m), 2.63-2.54 (0.5H, m), 1.39 (4.5H, s), 1.35 (4.5H, s), 1.33 (9H, s).
Example 10 1 -[(3-Methoxy-4-tert-butylphenyl)carbonyl]-2-(phenylmethyl)-4- [(phenylmethyl)sulfonyl]-piperazine-2-carboxylic acid
1 H NMR (de-DMSO): δ 12.85 (1H, br s), 7.44-7.27 (9H, m), 7.11 (2H, d), 6.76 (1H, d), 6.71 (1 H, s), 4.44 (2H, q), 3.81 (3H, s), 3.77 (1 H, d), 3.47-3.22 (4H, m), 3.12-3.05 (1H, m), 2.80 (1H, d), 2.68-2.58 (1H, m), 1.33 (9H, s).
Example 11
1-[(3-Methoxy-4-tert-butylphenyl)carbonyl]-2-(phenylmethyl)-piperazine-2- carboxylic acid hydrochloride
Example 12
1-[(3-Methoxy-4-tert-butylphenyl)carbonyl]-2-(phenylmethyl)-4-methyl-piperazine-2- carboxylic acid
Example 13
1-[(3-Methoxy-4-tert-butylphenyl)carbonyl]-2-(phenylmethyl)-4-(2-pyrimidinyl)- piperazine-2-carboxylic acid
1H NMR (de-DMSO): δ 12.52 (1H, br s), 8.34 (2H, d), 7.37-7.26 (6H, m), 6.82 (1H, d), 6.78 (1H, s), 6.62 (1H, t), 4.86 (1H, d), 3.86 (1H, d), 3.83 (3H, s), 3.78 (1H, d), 3.61-3.51 (2H, m), 3.22-3.15 (1 H, m), 3.03 (1H, d), 2.90-2.80 (1 H, m), 1.34 (9H, s).
Example 14
1-[(3-Methoxy-4-tert-butylphenyl)carbonyl]-2-(phenylmethyl)-4-(3- carboxypropanoyl)-piperazine-2-carboxylic acid
Example 15 1-[(3-Methoxy-4-tert-butyiphenyl)carbonyl]-2-(phenylmethyJ)-4-(carboxyacetyl)- piperazine-2-carboxylic acid H NMR (de-DMSO, mixture of rotamers): δ 7.40-7:23 (6H, m), 6.86-6.73 (2H, m), 4.41 (0.65H, d), 3.97 (0.35H, d), 3.86-3.75 (4.35H, m), 3.60-3.12 (7H, m), 3.03 (0.65H, d), 2.98 (1 H, d), 2.67 (1 H, t), 1.33 (9H, s).
Example 16
1-[(3-Methoxy-4-tert-butylphenyl)carbonyl]-2-(phenylmethyl)-4-acetyl-piperazine-2- carboxylic acid 1H NMR (CDCI3) mixture of rotamers): δ 7.39-7.30 (3H, m), 7.30-7.25 (3H, m), 7.06 (0.67H, s), 7.02 (0.33H, s), 6.88-6.80 (1 H, m), 4.78 (0.67H, d), 4.14 (1H, d), 4.00-3.90 (0.67H. dd), 3.88 (3H, s), 3.82-3.64 (2H, m), 3.56 (0.67H, d), 3.27-3.17 (1H, m), 3.11 (1 H, d), 2.99-2.84 (1 H, m), 2.17 (1H, s), 2.02 (2H, s), 1.38 (9H, s). Carboxylic acid proton is assumed to be exchanged with moisture in the solvent.
Example 17
1-[(3-Methoxy-4-tert-butylphenyl)carbonyl]-2-(2-methylpropyl)-4-(phenylsulfonyl)- piperazine-2-carboxylic acid
Example 18 1-[(3-Methoxy-4-tert-butylphenyl)carbonyl]-2-(2-methylpropyl)-4- [(phenylmethyl)sulfonyl]-piperazine-2 -carboxylic acid
Example 19
1-[(3-Methoxy-4-tert-butylphenyl)carbonyl]-2-(2-methylpropyl)-4-(carboxyacetyl)- piperazine-2-carboxylic acid
1H NMR (CDCI3, mixture of rotamers): δ 7.37-7.27 (1H, m), 7.11 (0.5H, s), 7.06 (0.5H, s), 7.00-6.90 (1H, m), 4.66 (0.5H, d), 4.15-3.28 (12.5H, m), 2.70-2.61 (0.5H, m), 2.58-2.50 (0.5H, m), 1.97-1.75 (2H, m), 1.38 (4.5H, s), 1.37 (4.5H, s), 1.10-0.98 (6H, m).
Example 20
1-[(3-Methoxy-4-tert-butylphenyl)carbonyl]-2-(2-methylpropyl)-4-(3- carboxypropanoyl)-piperazine-2-carboxylic acid
1H NMR (CDCI3, mixture of rotamers): δ 7.29 (1H, d), 7.03 (1H, s), 6.92 (1H, t), 4.70 (1H, d), 4.15-3.71 (8H, m), 3.63-3.44 (2H, m), 2.98-2.67 (3H, m), 2.60-2.44 (1H, m), 2.38-2.18 (1 H, m), 1.89-1.74 (2H, m), 1.37 (9H, s), 1.06 (3H, t), 1.00 (3H, t).
Example 21
1-[(3-Methoxy-4-tert-butylphenyl)carbonyl]-2-(2-methylpropyl)-4-acetyl-piperazine-2- carboxylic acid 1H NMR (CDCI3, mixture of rotamers): δ 7.33-7.27 (1 H, m), 7.11 (0.5H, s), 7.08 (0.5H, s), 7.01-6.92 (1 H, m), 4.61 (0.5H, d), 4.05 (1 H, d), 3.96-3.75 (5.5H, m), 3.68-3.58 (1.5H, m), 3.53-3.46 (0.5H, m), 2.63 (0.5H, dd), 2.44 (0.5H, dd), 2.20 (1.5H, s), 2.05 (1H, s), 2.00 (0.5H, dd), 1.92-1.78 (1.5H, m), 1.38 (4.5H, s), 1.37 (4.5H, s), 1.05 (3H, t), 1.01 (3H, t). Carboxylic acid proton is assumed to be exchanged with moisture in the solvent.
Example 22 1-[(3-Methoxy-4-tert-butylphenyl)carbonyl]-2-(2-methylpropyl)-4-(phenylcarbonyl)- piperazine-2-carboxylic acid
1 H NMR (CDCI3, mixture of rotamers, all signals broad): δ 7.50-7.30 (6H, m), 7.13-7.05 (1H, m), 7.03-6.89 (1H, m), 4.61-4.51 (0.35H, m), 4.05-3.70 (9H, m), 3.41-3.31 (0.65H, m), 2.69-2.58 (0.65H, m), 2.39-2.26 (1H, m), 2.05-1.77 (1.35H, m), 1.43-1.33 (9H, m), 1.12-0.99 (6H, m).
Example 23
1-[(3-Methoxy-4-tert-butylphenyl)carbonyl]-2-(2-methylpropyl)-4- [(ethylamino)carbonyl]-piperazine-2-carboxylic acid 1H NMR (CDCI3): δ 7.28 (1H, d), 7.07 (1H, d), 6.93 (1H, d), 4.63 (1 H, br s), 4.31 (1H, d), 3.87 (3H, s), 3.87-3.60 (4H, m), 3.37-3.16 (4H, m), 2.54 (1H, dd), 1.97-1.87 (1H, m), 1.87- 1.76 (1 H, m), 1.37 (9H, s), 1.12 (3H, t), 1.04 (3H, d), 0.98 (3H, d).
Example 24 1-[(3-Methoxy-4-tert-butylphenyl)carbonyl]-2-(2-methylpropyl)-4- [(phenylamino)carbonyl]-piperazine-2-carboxylic acid
1 H NMR (CDCI3): δ 7.32 (3H, t), 7.22 (2H, t), 7.08 (1 H, s), 7.01-6.94 (2H, m), 4.34 (1H, d), 3.85 (3H, s), 3.83-5.65 (5H, m), 3.46-3.37 (2H, m), 2.42 (1H, dd), 2.00-1.92 (1H, m), 1.86- 1.76 (1 H, m), 1.38 (9H, s), 1.03 (3H, d), 0.97 (3H, d).
Example 25
1-[(3-Methoxy-4-tert-butylphenyl)carbonyl]-2-(1,3-thiazol-4-ylmethyl)-4- (methylsulfonyl)-piperazine-2-carboxylic acid 1H NMR (d3-MeOD): δ 9.01 (1 H, d), 7.33 (1H, d), 7.28 (1 H, d), 6.71 (1 H, s), 6.65 (1H, d), 4.34 (1 H, d), 4.18 (1H, d), 3.88-3.83 (1H, m), 3.83 (3H, s), 3.65-3.59 (1H, m), 3.49-3.41 (1H, m), 3.36-3.24 (3H, m), 2.88 (3H, s), 1.34 (9H, s). Carboxylic acid proton is assumed to be exchanged with the solvent.
Example 26
1-[(3-Methoxy-4-tert-butylphenyl)carbonyl]-2-(1,3-thiazol-4-ylmethyl)-4-acetyl- piperazine-2-carboxylic acid
1H NMR (d3-MeOD, mixture of rotamers): δ 9.04 (1H, d), 7.33 (1H, m), 7.29 (1H, d), 6.77- 6.73 (1 H, m), 6.70-6.66 (1 H, m), 4.64 (0.55H, d), 4.58 (0.45H, d), 4.23 (0.45H, d), 4.22 (0.55H, d), 4.13 (0.55H, d), 4.07 (0.45H, d), 3.84 (1.65H, s), 3.83 (1.35H, s), 3.69-3.54 (2H, m), 3.42-3.36 (0.55H, m), 3.30-3.06 (2.45H, m), 2.11 (1.35H, s), 1.98 (1.65H, s), 1.34 (9H, s). Carboxylic acid proton is assumed to be exchanged with the solvent. Example 27 1-[(3-Methoxy-4-tert-butylphenyl)carbonyl]-2-(phenylmethyl)-4- {[(methylsulfonyl)methyl]sulfonyl}-piperazine-2-carboxylic acid 1H NMR (d3-MeOD): δ 7.39-7.28 (6H, m), 6.86-6.80 (2H, m), 5.02-4.96 (1H, m), 4.05-3.91 (3H, m), 3.84 (3H, s), 3.61-3.52 (2H, m), 3.19 (3H, s), 3.04 (1H, d), 2.90-2.79 (1H, m), 1.36 (9H, s). Carboxylic acid and S02CH2 protons are assumed to be exchanged with the solvent.
Example 28
1-[(3-Methoxy-4-tert-butylphenyl)carbonyl]-2-{1,3-thiazol-4-ylmethyl)-4- (phenylcarbonyl)-piperazine-2-carboxylic acid H NMR (d3-MeOD, mixture of rotamers): δ 9.06-9.02 (1H, m), 7.53-7.22 (7H, m), 6.76 (0.7H, m), 6.72-6.67 (1H, m), 6.62 (0.3H, d), 4.76 (0.3H, d), 4.64 (0.7H, d), 4.33 (0.3H, d), 4.26 (0.3H, d), 4.13 (0.7H, d), 3.88-3.78 (2H, m), 3.85 (2.1 H, s), 3.78 (0.9H, s), 3.70-3.67 (0.3H, m), 3.55-3.11 (2.7H, m), 2.97 (0.7H, d), 1.35 (6.3H, s), 1.31 (2.7H, s). Carboxylic acid proton is assumed to be exchanged with the solvent.
Example 29 1-[(3-Methoxy-4-tert-butylphenyl)carbonyl]-2-(1,3-thiazol-4-ylmethyl)-4- (phenylsulfonyl)-piperazine-2-carboxylic acid
1H NMR (d3-MeOD): δ 8.91 (1 H, s), 7.81 (2H, d), 7.71-7.56 (3H, m), 7.32 (1 H, s), 7.24 (1H, d), 6.67 (1H, s), 6.61 (1H, d), 4.13 (1H, d), 4.07 (1H, d), 3.79 (3H, s), 3.73 (1H, d), 3.58-3.49 (1 H, m), 3.36-3.07 (4H, m), 1.32 (9H, s). Carboxylic acid proton is assumed to be exchanged with the solvent.
Example 30
1 -[(3-Methoxy-4-tert-butylphenyl)carbonyl]-2-(1 ,3-thiazol-4-ylmethyl)-4-(1 ,3- benzoxazol-2-yl)-piperazine-2-carboxylic acid 1H NMR (CDCI3): δ 8.85 (1H, s), 7.35 (1 H, d), 7.22-7.15 (3H, m), 7.06 (1 H, t), 6.96 (1H, t), 6.83 (1H, s), 6.52 (1H, d), 4.79 (1 H, d), 4.53 (1H, d), 4.32 (1 H, d), 3.95-3.84 (1H, m), 3.81 (3H, s), 3.80-3.75 (1 H, m), 3.60 (1 H, d) 3.50-3.37 (2H, m), 1.35 (9H, s). Carboxylic acid proton is assumed to be exchanged with moisture in the solvent.
Example 31
1-[(3-Methoxy-4-tert-butylphenyl)carbonyl]-2-(1,3-thiazol-4-ylmethyl)-4-phenyl- piperazine-2-carboxylic acid
1H NMR (CDCI3): δ 8.98 (1H, s), 7.30-7.25 (2H, m), 7.13 (2H, t), 6.85 (1H, s), 6.75 (1H, d), 6.68-6.58 (3H, m), 4.23 (2H, t), 3.98 (1 H, d), 3.84 (3H, s), 3.71-3.67 (1 H, m), 3.57-3.46 (1H, m), 3.43-3.32 (2H, m), 3.09 (1H, br d), 1.35 (9H, s). Carboxylic acid proton is assumed to be exchanged with moisture in the solvent. Example 32
1-[(3-Methoxy-4-tertibutylphenyl)carbonyl]-2-(1,3-thiazol-4-ylmethyl)-4-(4- acetylphenyl)-piperazine-2-carboxylic acid
1H NMR (CDCI3): δ 8.85 (1 H, s), 7.85 (2H, d), 7.22 (1 H, d), 7.14 (1H, s), 6.90 (1H, s), 6.63 (2H, d), 6.53 (1 H, d), 4.62 (1H, d), 4.24 (1 H, d), 4.16 (1H. d), 3.88-3.82 (1H, m), 3.81 (3H, s), 3.69-3.62 (1H, m), 3.58-3.49 (1H, m), 3.45 (1H, d), 3.30 (1 H, br d), 2.50 (3H, s), 1.35 (9H, s). Carboxylic acid proton is assumed to be exchanged with moisture in the solvent.
Example 48 1 -[(3-Methoxy-4-tert-butylphenyl)carbonyl]-2-(1 ,3-thiazol-4-ylmethyl)-4- (cyclopentylcarbonyl)-piperazine-2-carboxylic acid
Figure imgf000043_0001
Figure imgf000044_0001
1-[(3-Methoxy-4-tert-butylphenyl)carbonyl]-2-(1,3-thiazol-4-ylmethyl)-4-(N- acetylglycyl)-piperazine-2-carboxylic acid
Figure imgf000045_0001
A stirred solution of Intermediate 40 (65 mg, 0.127 mmol) and triethylamine (971 uL, 0.51 mmol) in anhydrous DCM (2 mL) was cooled to 0°C and treated with acetyl chloride (9uL, 0.127 mmol). After 30 minutes the solvent was evaporated and the residue was purified by reverse phase HPLC on a Cι8 column using a two-solvent gradient elution with (A) water containing formic acid (0.1%) and (B) acetonitrile-water (95:5 v/v) containing formic acid (0.05%) as the eluents, and analysis of the fractions by electrospray mass spectroscopy. The fractions containing the desired product were combined and evaporated. The resultant residue was dissolved in dioxan and freeze-dried to give the title compound as a solid.
MS calcd for (C25H32N4O6S + H)+: 517. Found: (M+H)+ = 517.
1H NMR (d3-MeOD, mixture of rotamers): δ 9.03 (1H, s), δ 7.33 (1H, s), δ 7.29 (1H, d), δ 6.79-6.73 (1 H, m), δ 6.71-6.66 (1 H, m), δ 4.63-4.54 (1H, m), δ 4.27-4.17 (2H, m), δ 406- 3.89 (2H, m), δ 3.84 (1.8H, s), δ 3.83 (1.2H, s), δ 3.65-3.55 (2H, m), δ 3.42-3.11 (3H, m), δ 2.01 (1.2H, s), δ 1.99 (1.8H, s), δ 1.34 (9H, s). Carboxylic acid and MeCONH protons are assumed to be exchanged with the solvent.
Example 34
1-[(3-Methoxy-4-tert-butylphenyl)carbonyl]-2-(1,3-thiazol-4-ylmethyl)-4- [(phenyloxy)carbonyl]-piperazi
Figure imgf000045_0002
A stirred solution of Intermediate 38 ( 27 mg, 0.06 mmol) and DBU (36 uL, 0.24 mmol) in anhydrous DMF (1.5 ml) was treated with phenyl chloroformate (11uL, 0.09 mmol). The mixture was stirred at ambient temperature for 1 hour then partitioned between DCM and 2 M hydrochloric acid. The organic phase was separated and evaporated. The residue was purified by reverse phase HPLC on a Cι8 column using a two-solvent gradient elution with (A) water containing formic acid (0.1%) and (B) acetonitrile-water (95:5 v/v) containing formic acid (0.05%) as the eluents, and analysis of the fractions by electrospray mass spectroscopy. The fractions containing the desired product were combined and evaporated to give the title compound as a solid. MS calcd for (C28H3ιN3O6S + H)+: 538. Found: (M+Hf = 538. 1H NMR (d3-MeOD): δ 9.05 (1H, s), δ 7.42-7.26 (4H, m), δ 7.21 (1H, q), δ 7.14 (1H, d), δ 7.08 (1H, d), δ 6.79 (1H, s), δ 6.72 (1H, d), δ 4.51-4.23 (3H, m), δ 3.88-3.77 (4H, m), δ 3.71-3.56 (1H, m), δ 3.51-3.42 (1H, m), δ 3.29-3.08 (2H, m), δ 1.35 (9H, s). Carboxylic acid proton is assumed to be exchanged with the solvent.
Example 35
1 -[(3-Methoxy-4-tert-butylphenyl)carbonyl]-2-(1 ,3-thiazol-4-ylmethyl)-4-(1 H- benzimidazol-2-yl)-piperazine-2 -carboxylic acid hydrochloride
Figure imgf000046_0001
A solution of Intermediate 44 (18 mg, 0.0026) in THF (0.33 mL) and methanol (0.33 mL) was treated with 2 M sodium hydroxide (0.33 mL) and stirred at 70°C for 18 hours. The mixture was evaporated then partitioned between DCM and 2 M hydrochloric acid. The organic phase was separated, evaporated and stirred in a 4 M solution of hydrogen chloride in dioxan (1 mL) at ambient temperature for 18 hours. The mixture was evaporated and purified by reverse phase HPLC on a Ci8 column using a two-solvent gradient elution with (A) water containing formic acid (0.1%) and (B) acetonitrile-water (95:5 v/v) containing formic acid (0.05%) as the eluents, and analysis of the fractions by electrospray mass spectroscopy. The fractions containing the desired product were combined and evaporated to give a white solid which was freeze dried from a 4 M solution of hydrogen chloride in dioxan affording the title compound hyrochloride salt. MS calcd for (C28H3ιN5O4S + H)+: 534. Found: (M+H)+ = 534. 1H NMR (d6-DMSO): δ 13.25 (2H, br s), δ 9.19 (1H, s), δ 7.48-7.41 (3H, m), δ 7.32-7.25 (3H, m), δ 6.67 (1H, d), δ 6.64 (1H, s), δ 4.73 (1 H, d), δ 4.32 (1H, d), δ 4.11 (1 H, d), δ 3.83 (3H, s), δ 3.74-3.21 (4H, m), δ 3.12 (1H, d), δ 1.34 (9H, s). Carboxylic acid proton is assumed to be exchanged with the solvent.
Example 36 1 -[(3-Methoxy-4-tert-butylphenyl)carbonyl]-2-(1 ,3-thiazol-4-ylmethyl)-4-(1 ,3-thiazol-2- yl)-piperazine-2-carboxylic acid
Figure imgf000047_0001
To a solution of Intermediate 38 (100 mg, 0.22 mmol) and DBU (120 uL, 0.88 mmol) in anhydrous DMF (2 mL) was added 2-bromothiazole (30 uL, 0.33 mmol). The mixture was stirred at 95 °C for 18 hours, evaporated and partitioned between DCM and 2 M hydrochloric acid. The organic phase was separated, evaporated and purified by reverse phase HPLC on a Cι8 column using a two-solvent gradient elution with (A) water containing formic acid (0.1%) and (B) acetonitrile-water (95:5 v/v) containing formic acid (0.05%) as the eluents, and analysis of the fractions by electrospray mass spectroscopy. The fractions containing the desired product were combined and evaporated. The residue was freeze dried from dioxan to give the title compound as a solid. MS calcd for (C24H28N4O4S2 + H)+: 501. Found: (M+H)+ = 501.
1H NMR (d3-MeOD): δ 9.03 (1H, d), δ 7.34-7.27 (2H, m), δ 7.11 (1H, d), δ 6.76 (1 H, s), δ 6.69 (1 H, d), δ 6.65 (1H, d), δ 4.67 (1H, d), δ 4.32 (1 H, d), δ 4.24 (1H, d), δ 3.84 (3H, s), δ 3.73-3.66 (1 H, m), δ 3.60-3.51 (1H, m), δ 3.43-3.33 (1H, m), δ 3.32-3.24 (2H, m), δ 1.35 (9H, s). Carboxylic acid proton is assumed to be exchanged with the solvent.
Example 37
1 -[(3-Methoxy-4-tert-butylphenyl)carbonyl]-2-(1 ,3-thiazol-4-ylmethyl)-4- (2- pyrazinyl)-piperazine-2-carboxyiic acid
Figure imgf000047_0002
The title compound was prepared from Intermediate 38 and chloropyrazine using a similar procedure to that described for Example 34.
MS calcd for (C25H29N5O4S + H)+: 496. Found: (M+H)+ = 496.
1H NMR (d3-MeOD): δ 9.03 (1H, d), δ 8.07-8.05 (1H, m), δ 7.90 (1H, s), δ 7.76 (1 H, d), δ 7.33-7.30 (2H, m), δ 6.79 (1 H, s), δ 6.73 (1 H, d), δ 4.94 (1 H, d), δ 4.42 (1 H, d), δ 4.25 (1 H, d), δ 3.85 (3H, s), δ 3.76-3.69 (1 H, m), δ 3.63-3.55 (1 H, m), δ 3.43-3.31 (3H, m), δ 1.36
(9H, s). Carboxylic acid proton is assumed to be exchanged with the solvent. Example 38 1-[(3-Methoxy-4-tert-butylphenyl)carbonyl]-2-(1,3-thiazol-4-ylmethyl)-4- [(phenylamino)carbonyl]-pipe d
Figure imgf000048_0001
To a stirred solution of Intermediate 38 (80 mg, 0.176 mmol) in anhydrous DCM (2 mL) was added phenyl isocyanate (22uL, 0.2 mmol) then triethylamine (28uL, 0.2 mmol). After 0.5 hours more phenyl isocyanate (11uL, 0.1 mmol) was added. The mixture was stirred for a further 0.5 hours then quenched with water and evaporated. The resultant residue was partitioned between DCM and 2 M hydrochloric acid. The organic phase was separated, evaporated and purified by reverse phase HPLC on a C 8 column using a two- solvent gradient elution with (A) water containing formic acid (0.1%) and (B) acetonitrile- water (95:5 v/v) containing formic acid (0.05%) as the eluents, and analysis of the fractions by electrospray mass spectroscopy. The fractions containing the desired product were combined and evaporated. The residue was freeze dried from dioxan to give the title compound as a solid.
MS calcd for (C28H32N4O5S + H)+: 537. Found: (M+H)+ = 537.
1H NMR (d3-MeOD): δ 9.04 (1H, d), 7.37-7.21 (6H, m), 7.01 (1H, t), 6.78 (1H, s), 6.72 (1H, d), 4.47 (1H, d), 4.32 (1H, d), 4.23 (1 H, d), 3.85 (3H, s), 3.73-3.59 (2H, m), 3.37- 3.21 (3H, m), 1.35 (9H, s). Carboxylic acid proton is assumed to be exchanged with the solvent.
Example 39
1-[(3-Methoxy-4-tert-butylphenyl)carbonyl]-2-(1,3-thiazol-4-ylmethyl)-4-{[(3- chlorophenyl)amino]carbonyl}- c acid
Figure imgf000048_0002
A stirred solution of Intermediate 51 (40. mg, 0.06 mmol) in trifluoroacetic acid (1 mL) was stirred at 21 °C for 2.5 hours. The solution was then evaporated to a gum. Purification was achieved by reverse phase HPLC on a Cι8 column using a two-solvent gradient elution with (A) water containing formic acid (0.1%) and (B) acetonitrile-water (95:5 v/v) containing formic acid (0.05%) as the eluents, and analysis of the fractions by electrospray mass spectroscopy. The fractions containing the desired product were combined and evaporated to give the title compound as a solid. MS calcd for (C28H3iCIN4O5S + H)+: 571/573. Found: (M+H)+ = 571/573. 1H NMR (d3-CDCI3): δ 8.89 (1H, d), 7.4(1H, t), 7.18-7.26 (3H, m), 7.1 (1H, t), 6.94 (1H, dd), 6.87 (1 H, s), 6.68 (1H, bs) 4.8 (1H, d), 4.40 (1H, d), 4.28 (1 H, d), 4.03 (1H, d), δ 3.8 (3H,s), 3.37-3.78 (5H, m), 1.35 (9H, s), Carboxylic acid proton is assumed to be exchanged with moisture in the solvent.
The following compounds were prepared using a similar procedure to that described for Example 39:
Example 40
1-[(3-Methoxy-4-tert-butylphenyl)carbonyl]-2-(1,3-thiazol-4-ylmethyl)-4-{[(4- methoxyphenyl)amino]carbonyl}-piperazine-2 -carboxylic acid
1H NMR (d3-CDCI3): δ 8.87 (1H, d), 7.18-7.28 (4H, m), 6.89 (1H, s), 6.78 (1H, d), 6.68 (1H, d), 4.4 (1H, d), 4.26 (1 H, d), 4.00 (1H, d), 3.83 (3H, s), 3.74 (3H, s), 3.45-3.74 (7H, m). 1.35 (9H, s), Carboxylic acid proton is assumed to be exchanged with moisture in the solvent.
Example 41
1-[(3-Methoxy-4-tert-butylphenyl)carbonyl]-2-(1,3-thiazol-4-ylmethyl)-4- [(cyclohexylamino)carbonyl]-piperazine-2-carboxylic acid
1H NMR (d3-CDCI3): δ 8.84 (1H, d), 7.18-7.24 (2H, m), 6.87 (1H, s), 6.58 (1 H, d), 4.8
(1H, bs), 4.15-4.45 (7H, m), 3.84 (3H, s), 3.27-3.72 (5H, m), 1.95-1.5 (4H, m), 1.35
(9H, s), 1.00-1.2 (3H, m). Carboxylic acid proton is assumed to be exchanged with moisture in the solvent.
Example 42
1-[(3-Methoxy-4-tert-butylphenyl)carbonyl]-2-(1,3-thiazol-4-ylmethyl)-4-{[(2- methoxyphenyl)amino]carbonyl}-piperazine-2-carboxylic acid
1H NMR (d3-CDCI3): δ 8.85 (1 H, d), 8.1 (1H, m), 7.2-7.15 (2H, m), 7.03 (1H, bs), 6.85- 6.95 (3H, m), 6.75-6.85 (1H, m), 6.52 (1H, m), 4.54 (1H, d), 4.43 (1 H, d), 4.25 (1H, d), d 3.83 (3H, s), 3.80 (3H, s), 3.65-3.80 (2H, m), 3.35-3.5 (2H, m), 1.34 (9H, s). Carboxylic acid proton is assumed to be exchanged with moisture in the solvent.
Figure imgf000050_0001
Figure imgf000050_0003
Example 43 1-[(3-Methoxy-4-tert-butylphenyl)carbonyl]-2-(1,3-thiazol-4-ylmethyl)-4-{[(2- chlorophenyl)amino]carbonyl}- lic acid
Figure imgf000050_0002
A stirred solution of Intermediate 38 ( 80 mg, 0.18 mmol) and DBU (150 uL, 0.88 mmol) in anhydrous DMF (2 ml) was treated with 2-chlorophenyl isocyanate (26 uL, 0.20 mmol). The mixture was stirred at ambient temperature for 18 hours then evaporated. The residue was purified by reverse phase HPLC on a Cι8 column using a two-solvent gradient elution with (A) water containing formic acid (0.1%) and (B) acetonitrile-water (95:5 v/v) containing formic acid (0.05%) as the eluents, and analysis of the fractions by electrospray mass spectroscopy. The fractions containing the desired product were combined and evaporated to give the title compound as a solid.
MS calcd for (C28H3ιCIN4O5S + H)+: 571/573. Found: (M+H)+ = 571/573. 1H NMR (d3-CDCI3): δ 8.86 (1 H,d), 8.11 (1 H,d), 7.26 (1 H, d), 7.22-7.14 (3H, m), 7.05 (1H, m), 6.93-6.84 (2H, m) 6.51 (1 H, d), 4.56 (1H, d), 4.43 (1 H, d), 4.24 (1H, d), 3.82, (3H, s), 3.7-3.82 (2H, m), 3.35-3.5 (3H, m), 1.35 (9H, s). Carboxylic acid proton is assumed to be exchanged with moisture in the solvent. Example 44 1-[(3-Methoxy-4-tert-butylphenyl)carbonyl]-2-(1,3-thiazol-4-ylmethyl)-piperazine-2,4- dicarboxylic acid, 4-tert-butyl ester
Similarly prepared as described for Intermediate 37 above.
Example 45
1-[(3-Methoxy-4-tert-butylphenyl)carbonyl]-2-(1,3-thiazol-4-ylmethyl)-piperazine-2- carboxylic acid, hydrochloride
Similarly prepared as described for Intermediate 38 above.
Example 46
1-[(3-Methoxy-4-tert-butylphenyl)carbonyl]-2-(1,3-thiazol-4-ylmethyl)-4-[ V-(tert- butoxycarbonyl)glycyl]-piperazine-2 -carboxylic acid
Similarly prepared as described for Intermediate 39 above.
Example 47
1-[(3-Methoxy-4-tert-butylphenyl)carbonyl]-2-(1,3-thiazol-4-ylmethyl)-4-glycyl- piperazine-2-carboxylic acid hydrochloride
Similarly prepared as described for Intermediate 40 above.
The compounds according to the invention may be formulated for administration in any convenient way, and the invention therefore also includes within its scope pharmaceutical compositions for use in therapy, comprising a compound of formula (I) or a physiologically acceptable salt or solvate thereof in admixture with one or more physiologically acceptable diluents or carriers.
The compounds of the present invention can be administered by different routes including intravenous, intraperitoneal, subcutaneous, intramuscular, oral, topical, transdermal, or transmucosal administration. For systemic administration, oral administration is preferred. For oral administration, for example, the compounds can be formulated into conventional oral dosage forms such as capsules, tablets and liquid preparations such as syrups, elixirs and concentrated drops.
Alternatively, injection (parenteral administration) may be used, e.g., intramuscular, intravenous, intraperitoneal, and subcutaneous. For injection, the compounds of the invention are formulated in liquid solutions, preferably, in physiologically compatible buffers or solutions, such as saline solution, Hank's solution, or Ringer's solution. In addition, the compounds may be formulated in solid form and redissolved or suspended immediately prior to use. Lyophilized forms can also be produced.
Systemic administration can also be by transmucosal or transdermal means. For transmucosal or transdermal administration, penetrants appropriate to the barrier to be permeated are used in the formulation. Such penetrants are generally known in the art, and include, for example, for transmucosal administration, bile salts and fusidic acid derivatives. In addition, detergents may be used to facilitate permeation. Transmucosal administration, for example, may be through nasal sprays, rectal suppositories, or vaginal suppositories.
For topical administration, the compounds of the invention can be formulated into ointments, salves, gels, or creams, as is generally known in the art, including administration via a patch.
The amounts of various compounds to be administered can be determined by standard procedures taking into account factors such as the compound (IC50) potency, (EC50) efficacy, and the biological half-life (of the compound), the age, size and weight of the patient, and the disease or disorder associated with the patient. The importance of these and other factors to be considered are known to those of ordinary skill in the art.
Amounts administered also depend on the routes of administration and the degree of oral bioavailability. For example, for compounds with low oral bioavailability, relatively higher doses will have to be administered. Oral administration is a preferred method of administration of the present compounds.
Preferably the composition is in unit dosage form. For oral application, for example, a tablet, or capsule may be administered, for nasal application, a metered aerosol dose may be administered, for transdermal application, a topical formulation or patch may be administered and for transmucosal delivery, a buccal patch may be administered. In each case, dosing is such that the patient may administer a single dose.
Each dosage unit for oral administration contains suitably from 0.01 to 500 mg/Kg, and preferably from 0.1 to 50 mg/Kg, of a compound of Formula (I) or a pharmaceutically acceptable salt thereof, calculated as the free base. The daily dosage for parenteral, nasal, oral inhalation, transmucosal or transdermal routes contains suitably from 0.01 mg to 100 mg/Kg, of a compound of Formula(l). A topical formulation contains suitably 0.01 to 5.0% of a compound of Formula (I). The active ingredient may be administered from 1 to 6 times per day, preferably once, sufficient to exhibit the desired activity, as is readily apparent to one skilled in the art.
Composition of Formula (I) and their pharmaceutically acceptable salts which are active when given orally can be formulated as syrups, tablets, capsules and lozenges. A syrup formulation will generally consist of a suspension or solution of the compound or salt in a liquid carrier for example, ethanol, peanut oil, olive oil, glycerine or water with a flavoring or coloring agent. Where the composition is in the form of a tablet, any pharmaceutical carrier routinely used for preparing solid formulations may be used. Examples of such carriers include magnesium stearate, terra alba, talc, gelatin, acacia, stearic acid, starch, lactose and sucrose. Where the composition is in the form of a capsule, any routine encapsulation is suitable, for example using the aforementioned carriers in a hard gelatin capsule shell. Where the composition is in the form of a soft gelatin shell capsule any pharmaceutical carrier routinely used for preparing dispersions or suspensions may be considered, for example aqueous gums, celluloses, silicates or oils, and are incorporated in a soft gelatin capsule shell.
Typical parenteral compositions consist of a solution or suspension of a compound or salt in a sterile aqueous or non-aqueous carrier optionally containing a parenterally acceptable oil, for example polyethylene glycol, polyvinylpyrrolidone, lecithin, arachis oil or sesame oil.
Typical compositions for inhalation are in the form of a solution, suspension or emulsion that may be administered as a dry powder or in the form of an aerosol using a conventional non-CFC propellant such as 1 ,1 ,1 ,2-tetrafluoroethane or 1 ,1 ,1 ,2,3,3,3- heptafluoropropane.
A typical suppository formulation comprises a compound of Formula (I) or a pharmaceutically acceptable salt thereof which is active when administered in this way, with a binding and/or lubricating agent, for example polymeric glycols, gelatins, cocoa- butter or other low melting vegetable waxes or fats or their synthetic analogs.
Typical dermal and transdermal formulations comprise a conventional aqueous or non- aqueous vehicle, for example a cream, ointment, lotion or paste or are in the form of a medicated plaster, patch or membrane.
No unacceptable toxological effects are expected when compounds of the present invention are administered in accordance with the present invention.
ASSAY
The potential for compounds of the invention to inhibit NS5B wildtype HCV polymerase activity may be demonstrated, for example, using the following in vitro assay:
In Vitro Detection of inhibitors of HCV RNA-dependent RNA Polymerase Activity
Incorporation of [33P]-GMP into RNA was followed by absorption of the biotin labelled RNA polymer by streptavidin containing SPA beads. A synthetic template consisting of biotinylated 13mer-oligoG hybridised to polyrC was used as a homopolymer substrate.
Reaction Conditions were 0.5 μM [33P]-GTP (20 Ci/mMol), 1 mM Dithiothreitol, 20 mM MgCI2, 5mM MnCI2, 20 mM Tris-HCI, pH7.5, 1.6 μg/mL polyC/0.256 μM biotinylated oligoG13, 10% glycerol, 0.01 % NP-40, 0.2 u/μL RNasin and 50 mM NaCI.
HCV RNA Polymerase (Recombinant full-length NS5B (Lohmann et al, J. Virol. 71 (11 ), 1997, 8416 'Biochemical properties of hepatitis C virus NS5B RNA-dependent RNA polymerase and identification of amino acid sequence motifs essential for enzymatic activity') expressed in baculovirus and purified to homogeneity) was added to 4 nM final concentration.
5x concentrated assay buffer mix was prepared using 1 M MnCI2 (0.25 mL), glycerol (2.5mL), 10% NP-40 (0.025 mL) and Water (7.225 mL), Total 10 mL.
2x concentrated enzyme buffer contained 1M-Tris-HCI, pH7.5 (0.4 mL), 5M NaCI (0.2 mL), 1M-MgCI2 (0.4 mL), glycerol (1 mL), 10% NP-40 (10 μL), 1 M DTT (20 μL) and water (7.97 mL), Total 10 mL
Substrate Mix was prepared using 5x Concentrated assay Buffer mix (4μL), PJ-GTP (10 μCi/μL, 0.02μL), 25 μM GTP (0.4 μL), 40 u/μL RNasin (0.1 μL), 20 μg/mL polyrC/biotinylated-oligorG (1.6 μL), and Water (3.94 μL), Total 10 μL.
Enzyme Mix was prepared by adding 1mg/ml full-length NS5B polymerase (1.5 μL) to 2.81 mL 2x-concentrated enzyme buffer.
The Assay was set up using compound (1μL), Substrate Mix (10 μL), and Enzyme Mix
(added last to start reaction) (10 μL), Total 21 μL.
The reaction was performed in a U-bottomed, white, 96-well plate. The reaction was mixed on a plate-shaker, after addition of the Enzyme, and incubated for 1h at 22°C.
After this time, the reaction was stopped by addition of 40 μL 1.875 mg/ml streptavidin
SPA beads in 0.1 M EDTA. The beads were incubated with the reaction mixture for 1h at 22°C after which 120 μL 0.1 M EDTA in PBS was added. The plate was sealed, mixed centrifuged and incorporated radioactivity determined by counting in a Trilux (Wallac) or
Topcount (Packard) Scintillation Counter.
After subtraction of background levels without enzyme, any reduction in the amount of radioactivity incorporated in the presence of a compound, compared to that in the absence, was taken as a measure of the level of inhibition. Ten concentrations of compounds were tested in three- or fivefold dilutions. From the counts, percentage of inhibition at highest concentration tested or IC50S for the compounds were calculated using Grafit3, Grafit4 or Grafitδ software packages.
Of the exemplified compounds, those tested had an IC50 of <25μM in the above described assay. Accordingly, the compounds of the invention are of potential therapeutic benefit in the treatment and prophylaxis of HCV. Preferred compounds had an IC50 of <5μM.
The pharmaceutical compositions according to the invention may also be used in combination with other therapeutic agents, for example immune therapies (eg. Interferon, such as Interferon alfa-2a (Roferon-A; Hoffmann-La Roche), inteferon alpha-2b (Intron-A; Schering-Plough), interferon alfacon-1 (Infergen; Intermune), peginterferon alpha-2b (Peg-lntron; Schering-Plough) or peginterferon alpha-2a (Pegasys; Hoffmann-La Roche)), therapeutic vaccines, antifibrotic agents, anti-inflammatory agents such as corticosteroids or NSAIDs, bronchodilators such as beta-2 adrenergic agonists and xanthines (e.g. theophylline), mucolytic agents, anti-muscarinics, anti-leukotrienes, inhibitors of cell adhesion (e.g. ICAM antagonists), anthoxidants (eg N-acetylcysteine), cytokine agonists, cytokine antagonists, lung surfactants and/or antimicrobial and anti-viral agents (eg ribavirin and amantidine). The compositions according to the invention may also be used in combination with gene replacement therapy.
The invention thus provides, in a further aspect, a combination comprising a compound of formula (I) or a physiologically acceptable salt or solvate thereof together with another therapeutically active agent, especially interferon and/or ribavirin.
The combinations referred to above may conveniently be presented for use in the form of a pharmaceutical formulation and thus pharmaceutical formulations comprising a combination as defined above together with a pharmaceutically acceptable carrier thereof represent a further aspect of the invention.
The individual components of such combinations may be administered either sequentially or simultaneously in separate or combined pharmaceutical formulations. Appropriate doses of known therapeutic agents will be readily appreciated by those skilled in the art.
All publications, including but not limited to patents and patent applications cited in this specification are herein incorporated by reference as if each individual publication were specifically and individually indicated to be incorporated by reference as though fully set forth.

Claims

Claims 1. At least one chemical entity chosen from compounds of Formula (I)
Figure imgf000056_0001
wherein: A represents hydroxy or -NH2;
D represents aryl or heteroaryl;
E represents hydrogen, straight or branched chain -C^alkyl, -CO2R1, -C(O)R1a, -C(O)NR2R3, -SO2R\ -SO2NR2R3, aryl, arylCi-aalkyl, heteroaryl, heteroaryld-salkyl, heterocyclyl or heterocyclylCι-3alkyl;
R1 is selected from the group consisting of -Chalky!, aryl, arylCι-3alkyl, heteroaryl, heteroarylCι-3alkyl, heterocyclyl or heterocyclylCι-3alkyl;
R1a is selected from the group consisting of -Ci-ealkyl, aryl,
Figure imgf000056_0002
heteroaryl, heteroarylCι-3alkyl, heterocyclyl or heterocydylCι-3alkyl;
R2 and R3 are independently selected from hydrogen, -Ci-ealkyl, aryl and heteroaryl; or R2 and R3 together with the nitrogen atom to which they are attached form a 5 or 6 membered saturated cyclic group;
G represents -Ci-ealkyl, heterocyclylCι-3alkyl, arylCι-3alkyl or heteroarylCι-3alkyl;
and salts, solvates and esters thereof; provided that when A is hydroxy esterified to form -OR where R is selected from straight or branched chain alkyl, aralkyl, aryloxyalkyl, or aryl, then R is other than tetf-butyl.
2. At least one chemical entity chosen from compounds as claimed in claim 1 selected from the group consisting of:
1-[(3-Methoxy-4-tet -butylphenyl)carbonyl]-2-(2-methylpropyl)-4-(methylsulfonyl)- piperazine-2-carboxylic acid;
1-[(3-Methoxy-4-tetf-butylphenyl)carbonyl]-2-(phenylmethyl)-4-(phenylcarbonyl)- piperazine-2-carboxylic acid; 1-[(3-Methoxy-4-tert-butylphenyl)carbonyl]-2-(phenylmethyl)-4-(methylsulfonyl)- piperazine-2-carboxylic acid; 1-[(3-Methoxy-4-tet/-butylphenyl)carbonyl]-2-(phenylmethyl)-4-(phenylsulfonyl)- piperazine-2-carboxylic acid; 1-[(3-Methoxy-4-tert-butylphenyl)carbonyl]-2,4-bis(phenylmethyl)-piperazine-2-carboxylic acid; 1-[(3-Methoxy-4-tert-butylphenyl)carbonyl]-2-(phenylmethyl)-4-[(phenylamino)carbonyl]- piperazine-2-carboxylic acid;
1-[(3-Methoxy-4-terf-butylphenyl)carbonyl]-2-(phenylmethyl)-4-[(ethylamino)carbonyl]- piperazine-2-carboxylic acid;
1-[(3-Methoxy-4-tert-butylphenyl)carbonyl]-2-(phenylmethyl)-piperazine-2,4-dicarboxylic acid, 4-methyl ester;
1-[(3-Methoxy-4-/e/ -butylphenyl)carbonyl]--2-(phenylmethyl)-piperazine-2,4-dicarboxylic acid, 4-tetf-butyl ester;
1-[(3-Methoxy-4-tert-butylphenyl)carbonyl]-2-(phenylmethyl)-4-[(phenylmethyl)sulfonyl]- piperazine-2-carboxylic acid; 1 -[(3-Methoxy-4-fetf-butylphenyl)carbonyl]-2-(phenylmethyl)-piperazine-2-carboxylic acid hydrochloride;
1-[(3-Methoxy-4-tert-butylphenyl)carbonyl]-2-(phenylmethyl)-4-methyl-piperazine-2- carboxylic acid;
1-[(3-Methoxy-4-te Y-butylphenyl)carbonyl]-2-(phenylmethyl)-4-(2-pyrimidinyl)-piperazine- 2-carboxylic acid;
1-[(3-Methoxy-4-fe/t-butylphenyl)carbonyl]-2-(phenylmethyl)-4-(3-carboxypropanoyl)- piperazine-2-carboxylic acid;
1-[(3-Methoxy-4-te/ -butylphenyl)carbonyl]-2-(phenylmethyl)-4-(carboxyacetyl)-piperazine-
2-carboxylic acid; 1-[(3-Methoxy-4-tert-butylphenyl)carbonyl]-2-(phenylmethyl)-4-acetyl-piperazine-2- carboxylic acid;
1-[(3-Methoxy-4-te -butylphenyl)carbonyl]-2-(2-methylpropyl)-4-(phenylsulfonyl)- piperazine-2-carboxylic acid;
1-[(3-Methoxy-4-tert-butylphenyl)carbonyl]-2-(2-methylpropyl)-4-[(phenylmethyl)sulfonyl]- piperazine-2-carboxylic acid;
1-[(3-Methoxy-4-terf-butylphenyl)carbonyl]-2-(2-methylpropyl)-4-(carboxyacetyl)- piperazine-2-carboxylic acid;
1-[(3-Methoxy-4-tert-butylphenyl)carbonyl]-2-(2-methylpropyl)-4-(3-carboxypropanoyl)- piperazine-2-carboxylic acid; 1-[(3-Methoxy-4-tett-butylphenyl)carbonyl]-2-(2-methylpropyl)-4-acetyl-piperazine-2- carboxylic acid;
1-[(3-Methoxy-4-terf-butylphenyl)carbonyl]-2-(2-methylpropyl)-4-(phenylcarbonyl)- piperazine-2-carboxylic acid;
1-[(3-Methoxy-4-tert-butylphenyl)carbonyl]-2-(2-methylpropyl)-4-[(ethylamino)carbonyl]- piperazine-2-carboxylic acid;
1-[(3-Methoxy-4-tert-butylphenyl)carbonyl]-2-(2-methylpropyl)-4-[(phenylamino)carbonyl]- piperazine-2-carboxylic acid; 1-[(3-Methoxy-4-tert-butylphenyl)carbonyl]-2-(1,3-thiazol-4-ylmethyl)-4-(methylsulfonyl)- piperazine-2-carboxylic acid; 1-[(3-Methoxy-4-tert-butylphenyl)carbonyl]-2-(1,3-thiazol-4-ylmethyl)-4-acetyl-piperazine-
2-carboxylic acid; 1-[(3-Methoxy-4-tetf-butylphenyl)carbonyl]-2-(phenylmethyl)-4-{[(methylsulfonyl)methyl]- sulfonyl}-piperazine-2-carboxylic acid 1-[(3-Methoxy-4-tet--butylphenyl)carbonyl]-2-(1 ,3- thiazol-4-ylmethyl)-4-(phenylcarbonyl)-piperazine-2-carboxylic acid; 1-[(3-Methoxy-4-tert-butylphenyl)carbonyl]-2-(1,3-thiazol-4-ylmethyl)-4-(phenylsulfonyl)- piperazine-2-carboxylic acid; 1 -[(3-Methoxy-4-terf-butylphenyl)carbonyl]-2-(1 ,3-thiazol-4-ylmethyl)-4-(1 ,3-benzoxazol-2- yl)-piperazine-2-carboxylic acid; 1-[(3-Methoxy-4-terf-butylphenyl)carbonyl]-2-(1,3-thiazol-4-ylmethyl)-4-phenylpiperazine-
2-carboxylic acid;
1-[(3-Methoxy-4-ter.-butylphenyl)carbonyl]-2-(1,3-thiazol-4-ylmethyl)-4-(4-acetylphenyl)- piperazine-2-carboxylic acid
1-[(3-Methoxy-4-tert-butylphenyl)carbonyl]-2-(1,3-thiazol-4-ylmethyl)-4-(N-acetylglycyl)- piperazine-2-carboxylic acid;
1-[(3-Methoxy-4-tetf-butylphenyl)carbonyl]-2-(1,3-thiazol-4-ylmethyl)-4-
[(phenyloxy)carbonyl]-piperazine-2-carboxylic acid; 1-[(3-Methoxy-4-tett-butylphenyl)carbonyl]-2-(1 ,3-thiazol-4-ylmethyl)-4-(1H-benzimidazol-
2-yl)-piperazine-2-carboxylic acid hydrochloride;
1-[(3-Methoxy-4-tetf-butylphenyl)carbonyl]-2-(1 ,3-thiazol-4-ylmethyl)-4-(1 ,3-thiazol-2-yl)- piperazine-2-carboxylic acid;
1-[(3-Methoxy-4-fert-butylphenyl)carbonyl]-2-(1 ,3-thiazol-4-ylmethyl)-4- (2-pyrazinyl)- piperazine-2-carboxylic acid;
1-[(3-Methoxy-4-fert-butylphenyl)carbonyl]-2-(1,3-thiazol-4-ylmethyl)-4-
[(phenylamino)carbonyl]-piperazine-2-carboxylic acid;
1-[(3-Methoxy-4-terf-butylphenyl)carbonyl]-2-(1,3-thiazol-4-ylmethyl)-4-{[(3- chlorophenyl)amino]carbonyl}-piperazine-2-carboxylic acid; 1 -[(3-Methoxy-4-tert-butylphenyl)carbonyl]-2-(1 ,3-thiazol-4-ylmethyl)-4-{[(4-
(methoxyphenyl)amino]carbonyl}-piperazine-2-carboxylic acid;
1-[(3-Methoxy-4-tert-butylphenyl)carbonyl]-2-(1,3-thiazol-4-ylmethyl)-4-
[(cyclohexylamino)carbonyl]-piperazine-2-carboxylic acid; 1 -[(3-Methoxy-4-tert- butylphenyl)carbonyl]-2-(1 ,3-thiazol-4-ylmethyl)-4-{[(2-methoxyphenyl)amino]carbonyl}- piperazine-2-carboxylic acid; 1-[(3-Methoxy-4-tert-butylphenyl)carbonyl]-2-(1,3-thiazol-4- ylmethyl)-4-{[(2-chlorophenyl)amino]carbonyl}-piperazine-2-carboxylic acid;
1-[(3-Methoxy-4-terf-butylphenyl)carbonyl]-2-(1,3-thiazol-4-ylmethyl)-piperazine-2,4- dicarboxylic acid, 4-fert-butyl ester;
1-[(3-Methoxy-4-tert-butylphenyl)carbonyl]-2-(1,3-thiazol-4-ylmethyl)-piperazine-2- carboxylic acid, hydrochloride;
1-[(3-Methoxy-4-tert-butylphenyl)carbonyl]-2-(1 ,3-thiazol-4-ylmethyl)-4-[Λ/-(tert- butoxycarbonyl)glycyl]-piperazine-2-carboxylic acid; 1-[(3-Methoxy-4-tert-butylphenyl)carbonyl]-2-(1 ,3-thiazol-4-ylmethyl)-4-glycyl-piperazine- 2-carboxylic acid hydrochloride; 1-[(3-Methoxy-4-tert-butylphenyl)carbonyl]-2-(1 ,3-thiazol-4-ylmethyl)-4- (cyclopentylcarbonyl)-piperazine-2-carboxylic acid;
and salts, solvates and esters, and individual enantiomers thereof where appropriate.
3. At least one chemical entity chosen from compounds of Formula (I) as claimed in claim 1 wherein A represents hydroxy.
4. At least one chemical entity chosen from compounds of Formula (I) as claimed in claim 1 wherein D represents optionally substituted phenyl.
5. At least one chemical entity chosen from compounds of Formula (I) as claimed in claim 4 wherein D represents para-terf-butylphenyl optionally further substituted by halo,
-Chalky! or -Ci-salkoxy.
6. At least one chemical entity chosen from compounds of Formula (I) as claimed in claim 1 wherein E represents hydrogen, methyl, Ph, -PhC(O)CH3, -C(O)Me, -C(O)Ph, -C(O)-cyclopentyl, -C(O)NHPh, -C(O)NH-2-CIPh, -C(O)NH-3-CIPh, -C(O)NH-2-MeOPh, -C(O)NH-4-MeOPh, -C(O)NH-cyclohexyl, -C(O)NHEt, -C(O)CH2NHC(O)CH3, -C(O)(CH2)2CO2H, -C(O)CH2CO2H, -CO2Me, -CO2.-Bu, -CO2Ph, -CH2Ph, -SO2Me, -SO2Ph, -SO2CH2Ph, -SO2CH2SO2Me, pyrimidin-2-yl, 1 ,3-benzoxazol-2-yl, 1 H- benzimidazol-2-yl, 1,3-thiazol-2-yl, pyrazin-2-yl.
7. At least one chemical entity chosen from compounds of Formula (I) as claimed in claim 6 wherein E represents hydrogen, methyl, -C(O)Me, -C(O)Ph, -C(O)NHPh, -C(O)NHEt, -C(O)(CH2)2CO2H, -C(O)CH2CO2H, -CO2Me, -CO2f-Bu, -CH2Ph, -SO2Me, -SO2Ph, -SO2CH2Ph, -SO2CH2SO2Me, or pyrimidin-2-yl.
8. At least one chemical entity chosen from compounds of Formula (I) as claimed in claim 1 wherein G represents Ci-ealkyl, arylalkyl or heteroarylalkyl.
9. At least one chemical entity chosen from compounds of Formula (I) as claimed in claim 8 wherein G represents isobutyl, prop-2-enyl, benzyl, 1 , 3-th iazol-4-y I methyl, or pyridylmethyl.
10. At least one chemical entity chosen from compounds of Formula (I) as claimed in claim 1 , and pharmaceutically acceptable salts and solvates thereof.
11. A method of treating or preventing viral infection which comprises administering to a subject in need thereof, an effective amount of at least one chemical entity chosen from compound of Formula (I)
Figure imgf000060_0001
wherein:
A represents hydroxy or -NH2;
D represents aryl or heteroaryl;
E represents hydrogen, straight or branched chain -Ci-βalkyl, -CO2R1, -C(O)R1a, -C(O)NR2R3, -SO2R1, -SO NR2R3, aryl, arylCi-aalkyl, heteroaryl, heteroarylCι-3alkyl, heterocyclyl or heterocyclylC^alkyl;
R1 is selected from the group consisting of -Ci-ealkyl, aryl, arylCι-3alkyl, heteroaryl, heteroarylCι-3alkyl, heterocyclyl or heterocyclylCι-3alkyl;
R1a is selected from the group consisting of -Cι-6alkyl, aryl, arylCι-3alkyl, heteroaryl, heteroaryld-salkyl, heterocyclyl or heterocyclylCLsalkyl;
R2 and R3 are independently selected from hydrogen, -Ci-βalkyl, aryl and heteroaryl; or R2 and R3 together with the nitrogen atom to which they are attached form a 5 or 6 membered saturated cyclic group;
G represents -Chalky!, heterocyclylCι-3alkyl, arylCι.3alkyl or heteroaryld-salkyl;
and salts, solvates and esters thereof; provided that when A is hydroxy esterified to form -OR where R is selected from straight or branched chain alkyl, aralkyl, aryloxyalkyl, or aryl, then R is other than ferf-butyl.
12. A method as claimed in claim 11 which involves inhibiting HCV replication.
13. A method as claimed in claim 11 in which the compound is administered in an oral dosage form.
14. At least one chemical entity chosen from compounds of Formula (I)
Figure imgf000061_0001
wherein:
A represents hydroxy or -NH2;
D represents aryl or heteroaryl;
E represents hydrogen, straight or branched chain -C^alkyl, -CO2R1, -C(O)R1a, -C(O)NR2R3, -SO2R\ -SO2NR2R3, aryl, aryld-salkyl, heteroaryl, heteroarylCι-3alkyl, heterocyclyl or heterocyclylCι.3alkyl;
R1 is selected from the group consisting of -Ci-ealkyl, aryl, arylCι-3alkyl, heteroaryl, heteroaryld-salkyl, heterocyclyl or heterocyclylCι-3alkyl;
R1a is selected from the group consisting of -Ci-ealkyl, aryl, arylC^alkyl, heteroaryl, heteroarylCi-salkyl, heterocyclyl or heterocyclylCι-3alkyl;
R2 and R3 are independently selected from hydrogen, -Ci-ealkyl, aryl and heteroaryl; or R2 and R3 together with the nitrogen atom to which they are attached form a 5 or 6 membered saturated cyclic group;
G represents -Ci-ealkyl, heterocyclylCι-3alkyl, arylCι-3alkyl or heteroarylCι-3alkyl;
and salts, solvates and esters thereof; provided that when A is hydroxy esterified to form -OR where R is selected from straight or branched chain alkyl, aralkyl, aryloxyalkyl, or aryl, then R is other than tert-butyl; for use in medical therapy.
15. A compound as claimed in claim 14 wherein the medical therapy is the treatment of viral infection.
16. A compound as claimed in claim 15 wherein the viral infection is HCV.
17. Use of at least one chemical entity chosen from compounds of Formula (I)
Figure imgf000062_0001
wherein:
A represents hydroxy or -NH2;
D represents aryl or heteroaryl;
E represents hydrogen, straight or branched chain -C^alkyl, -CO2R1, -C(O)R1a, -C(O)NR2R3, -SO2R\ -SO2NR2R3, aryl, aryld-aalkyl, heteroaryl, heteroaryld-salkyl, heterocyclyl or heterocyclylCι-3alkyl;
R1 is selected from the group consisting of -Ci-ealkyl, aryl, aryld-3alkyl, heteroaryl, heteroaryld-salkyl, heterocyclyl or heterocyclyld-3alkyl;
R1a is selected from the group consisting of -Ci-ealkyl, aryl, arylCι-3alkyl, heteroaryl, heteroaryld-salkyl, heterocyclyl or heterocyclylCι-3alkyl;
R2 and R3 are independently selected from hydrogen, -Ci-ealkyl, aryl and heteroaryl; or R2 and R3 together with the nitrogen atom to which they are attached form a 5 or 6 membered saturated cyclic group;
G represents -C^alkyl, heterocyclyld-3alkyl, arylCι.3alkyl or heteroarylCι-3alkyl;
and salts, solvates and esters thereof; provided that when A is hydroxy esterified to form -OR where R is selected from straight or branched chain alkyl, aralkyl, aryloxyalkyl, or aryl, then R is other than tert-butyl; in the manufacture of a medical for the treatment of viral infection.
18. Use as claimed in claim 17, wherein the viral infection is HCV.
19. A pharmaceutical formulation comprising at least one chemical entity chosen from compound of Formula (I) and salts, solvates and esters thereof as defined in claim 1, in conjunction with at least one pharmaceutically acceptable diluent or carrier.
20. A process for the preparation of a compound of Formula (I) as defined in claim 1 , comprising treatment of a compound of Formula (II)
Figure imgf000063_0001
in which A is alkoxy, and D, E and G are as defined for Formula (I), with an acid.
21. A process as claimed in claim 20 in which A is tert-butoxy.
PCT/EP2005/001451 2004-02-13 2005-02-10 4-acyl-piperazines as anti-viral agents WO2005079799A1 (en)

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Cited By (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2008098859A1 (en) * 2007-02-15 2008-08-21 F. Hoffmann-La Roche Ag Hcv polymerase inhibitors
WO2011079114A1 (en) 2009-12-23 2011-06-30 Elan Pharmaceuticals, Inc. Pteridinones as inhibitors of polo - like kinase
WO2012048129A2 (en) 2010-10-08 2012-04-12 Elan Pharmaceuticals, Inc. Inhibitors of polo-like kinase
EP2494991A1 (en) 2007-05-04 2012-09-05 Vertex Pharmaceuticals Incorporated Combination therapy for the treatment of HCV infection
CN105920004A (en) * 2016-05-24 2016-09-07 暨南大学 Application of 1,2,4-trisubstituted piperazine compound to preparation of anti-influenza virus medicine

Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO1999058526A1 (en) * 1998-05-13 1999-11-18 Dong Wha Pharm. Ind. Co., Ltd. Novel 2,5-pyridinedicarboxylic acid derivatives
WO2000001677A1 (en) * 1998-07-06 2000-01-13 Universite Paris 7 - Denis Diderot Piperazine derivatives inhibiting human immunodeficiency virus replication
WO2002026720A2 (en) * 2000-09-29 2002-04-04 Millennium Pharmaceuticals, Inc. PIPERAZINE BASED INHIBITORS OF FACTOR Xa
WO2002046171A2 (en) * 2000-12-06 2002-06-13 Signal Pharmaceuticals, Inc. Anilinopyrimidine derivatives as ikk inhibitors and compositions and methods related thereto
WO2003084953A1 (en) * 2002-04-04 2003-10-16 B & C Biopharm 6-(4-substituted-anilino)pyrimidine derivatives, method for the preparation thereof and antiviral pharmaceutical composition comprising the same

Patent Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO1999058526A1 (en) * 1998-05-13 1999-11-18 Dong Wha Pharm. Ind. Co., Ltd. Novel 2,5-pyridinedicarboxylic acid derivatives
WO2000001677A1 (en) * 1998-07-06 2000-01-13 Universite Paris 7 - Denis Diderot Piperazine derivatives inhibiting human immunodeficiency virus replication
WO2002026720A2 (en) * 2000-09-29 2002-04-04 Millennium Pharmaceuticals, Inc. PIPERAZINE BASED INHIBITORS OF FACTOR Xa
WO2002046171A2 (en) * 2000-12-06 2002-06-13 Signal Pharmaceuticals, Inc. Anilinopyrimidine derivatives as ikk inhibitors and compositions and methods related thereto
WO2003084953A1 (en) * 2002-04-04 2003-10-16 B & C Biopharm 6-(4-substituted-anilino)pyrimidine derivatives, method for the preparation thereof and antiviral pharmaceutical composition comprising the same

Cited By (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2008098859A1 (en) * 2007-02-15 2008-08-21 F. Hoffmann-La Roche Ag Hcv polymerase inhibitors
EP2494991A1 (en) 2007-05-04 2012-09-05 Vertex Pharmaceuticals Incorporated Combination therapy for the treatment of HCV infection
WO2011079114A1 (en) 2009-12-23 2011-06-30 Elan Pharmaceuticals, Inc. Pteridinones as inhibitors of polo - like kinase
WO2011079118A1 (en) 2009-12-23 2011-06-30 Elan Pharmaceuticals, Inc Pteridinones as inhibitors of polo-like kinase
WO2012048129A2 (en) 2010-10-08 2012-04-12 Elan Pharmaceuticals, Inc. Inhibitors of polo-like kinase
CN105920004A (en) * 2016-05-24 2016-09-07 暨南大学 Application of 1,2,4-trisubstituted piperazine compound to preparation of anti-influenza virus medicine
CN105920004B (en) * 2016-05-24 2018-10-09 暨南大学 Purposes of 1,2,4- tri- substituted piperazine like compound in preparing anti-influenza virus medicament

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