WO2006065590A2

WO2006065590A2 - Pyridine and pyrimidine antiviral compositions

Info

Publication number: WO2006065590A2
Application number: PCT/US2005/044206
Authority: WO
Inventors: C. Richard Wobbe
Original assignee: Xtl Biopharmaceuticals Inc.
Priority date: 2004-12-16
Filing date: 2005-12-05
Publication date: 2006-06-22
Also published as: WO2006065590A3

Abstract

The present invention relates to pyridines and pyrimidine derivatives of formula (I) wherein R1, R2, R3, R4 and R5 are as defined herein, and their pharmaceutical compositions useful as antiviral compounds, and their methods of preparation and methods for use in the treatment as antiviral agents.

Description

PYRIDINE AND PYRIMIDINE ANTIVIRAL COMPOSITIONS

BACKGROUND OF THE INVENTION

Hepatitis C virus (HCV) is considered to be the major etiological agent of non-A non-B (NANB) hepatitis, chronic liver disease, and hepatocellular carcinoma (HCC) around the world. The viral infection accounts for greater than 90% of transfusion-associated hepatitis in U.S. and it is the predominant form of hepatitis in adults over 40 years of age. Almost all of the infections result in chronic hepatitis and nearly 20% develop liver cirrhosis.

The virus particle has not been well characterized due to the lack of an efficient in vitro replication system and the extremely low amount of HCV particles in infected liver tissues or blood. However, molecular cloning of the viral genome has been accomplished by isolating the messenger RNA (mRNA) from the serum of infected chimpanzees then cloned using recombinant methodologies. [Grakoui A. et al. J. Virol. 67: 1385-1395 (1993)]. It is now known that HCV contains a positive strand RNA genome comprising approximately 9400 nucleotides, whose organization is similar to that of flaviviruses and pestiviruses. The genome of HCV, like that of flavi- and pestiviruses, encodes a single large polyprotein of about 3000 amino acids which undergoes proteolysis to form mature viral proteins in infected cells.

Cell-free translation of the viral polyprotein and cell culture expression studies have established that the HCV polyprotein is processed by cellular and viral proteases to produce the putative structural and nonstructural (NS) proteins. At least nine mature viral proteins are produced from the polyprotein by specific proteolysis. The order and nomenclature of the cleavage products are as follows: NH₂-C-El -E2-NS2-NS3-NS4A-NS4B-NS5A-NS5B-COOH. The three amino terminal putative structural proteins, C (capsid), El, and E2 (two envelope glycoproteins), are believed to be cleaved by host signal peptidases of the endoplasmic reticulum (ER).

The host enzyme is also responsible for generating the amino terminus of NS2. The proteolytic processing of the nonstructural proteins are carried out by the viral proteases: NS2-3 and NS3, contained within the viral polyprotein. The NS2-3 protease catalyzes the cleavage between NS2 and NS3. It is a metalloprotease and requires both NS2 and the protease domain of NS3. The NS5B RdRp catalyzes the rest of the cleavages of the substrates in the nonstructural part of the polyprotein. The NS3 protein contains 631 amino acid residues and is comprised of two enzymatic domains: the protease domain contained within amino acid residues 1-181 and a helicase ATPase domain contained within the rest of the protein. It is not known if the 70 kD NS3 protein is cleaved further in infected cells to separate the protease domain from the helicase domain, however, no cleavage has been observed in cell culture expression studies. The NS5B RdRp is a member of the serine proteinase class of enzymes. It contains His, Asp, and Ser as the catalytic triad. Mutation of the catalytic triad residues abolishes the cleavages at substrates NS3/4A, NS4A/4B, NS4B/5A, and NS5A/5B. The cleavage between NS3 and NS4A is mediated through an intramolecular enzymatic reaction, whereas the cleavages at NS4A/4B, 4B/5A, 5A/5B sites occur in a trans enzymatic reaction.

Experiments using transient expression of various forms of HCV NS polyproteins in mammalian cells have established that the NS3 serine protease is necessary but not sufficient for efficient processing of all these cleavages. Like flaviviruses, the HCV NS5B RdRp also requires a cofactor to catalyze some of these cleavage reactions. In addition to the serine protease NS3, the NS4A protein is absolutely required for the cleavage of the substrate at the NS3/4A and 4B/5A sites and increases the efficiency of cleavage of the substrate between 5A/5B, and possibly 4A/4B. Because the HCV NS5B RdRp cleaves the non-structural HCV proteins which are necessary for the HCV replication, the NS5B RdRp can be a target for the development of therapeutic agents against the HCV virus. Thus there is a need for the development of inhibitors of the HCV protease.

An HCV protease necessary for polypeptide processing and viral replication has been identified, cloned and expressed. See Houghton et al., U.S. Pat. No. 5,712,145. This approximately 3000 amino acid polyprotein contains, from the amino terminus to the carboxy terminus, a nucleocapsid protein (C), envelope proteins (El and E2) and several non-structural proteins, including NS 1 , 2, 3, 4a, 5a and 5b. NS3 is an approximately 68 kda protein, encoded by approximately 1893 nucleotides of the HCV genome, and has two distinct domains: (a) a serine protease domain consisting of approximately 200 of the N-terminal amino acids; and (b) an RNA-dependent ATPase domain at the C-terminus of the protein. The NS5B RdRp is considered a member of the chymotrypsin family because of similarities in protein sequence, overall three-dimensional structure and mechanism of catalysis. Other chymotrypsin-like enzymes are elastase, factor Xa, thrombin, trypsin, plasmin, urokinase, tPA and PSA. The HCV NS3 serine protease is responsible for proteolysis of the polypeptide (polyprotein) at the NS3/NS4a, NS4a/NS4b, NS4b/NS5a and NS5a/NS5b junctions and is thus responsible for generating four viral proteins during viral replication. This has made the HCV NS3 serine protease an attractive target for antiviral chemotherapy. It has been determined that the NS4a protein, an approximately 6 kda polypeptide, is a co-factor for the serine protease activity of NS3. Autocleavage of the NS3/NS4a junction by the NS3/NS4a serine protease occurs intramolecularly (i.e., cis) while the other cleavage sites are processed intermolecularly. Analysis of the natural cleavage sites for HCV protease revealed the presence of cysteine at Pl and serine at Pl ' and that these residues are strictly conserved in the NS4a/NS4b, NS4b/NS5a and NS5a/NS5b junctions. The NS3/NS4a junction contains a threonine at Pl and a serine at Pl '. The Cys → Thr substitution at NS3/NS4a is postulated to account for the requirement of cis rather than trans processing at this junction. See, e.g., Pizzi et al. (1994) Proc. Natl. Acad. Sci (USA) 91 :888-892, Failla et al. (1996) Folding & Design 1 :35-42. The NS3/NS4a cleavage site is also more tolerant of mutagenesis than the other sites. See, e.g., Kollykhalov et al. (1994) J. Virol. 68:7525-7533. It has also been found that acidic residues in the region upstream of the cleavage site are required for efficient cleavage. See, e.g., Komoda et al. (1994) J. Virol. 68:7351-7357. Inhibitors of HCV protease that have been reported include antioxidants (see for example

International Patent Application Publication No. WO 98/14181), certain peptides and peptide analogs (see for example International Patent Application Publication No. WO 98/17679, Landro et al. (1997) Biochem. 36:9340-9348, Ingallinella et al. (1998) Biochem. 37:8906-8914, Llinas-Brunet et al. (1998) Bioorg. Med. Chem. Lett. 8:1713-1718), inhibitors based on the 70- amino acid polypeptide eglin c (Martin et al. (1998) Biochem. 37:11459-11468, inhibitors affinity selected from human pancreatic secretory trypsin inhibitor (hPSTI-C3) and minibody repertoires (MBip) (Dimasi et al. (1997) J. Virol. 71:7461-7469), cV_H E2 (a "camelized" variable domain antibody fragment) (Martin et al.(1997) Protein Eng. 10:607-614), and αl- antichymotrypsin (ACT) (Elzouki et al.) (1997) J. Hepat. 27:42-28). A ribozyme designed to selectively destroy hepatitis C virus RNA has recently been disclosed (see, BioWorld Today

9(217): 4 (Nov. 10, 1998)). Reference is also made to the PCT Publications, No. WO 98/17679, published April 30, 1998; WO 98/22496, published May 28, 1998; and WO 99/07734, published February 18, 1999.

HCV has been implicated in cirrhosis of the liver and in induction of hepatocellular carcinoma. The prognosis for patients suffering from HCV infection is currently poor. HCV infection is more difficult to treat than other forms of hepatitis due to the lack of immunity or remission associated with HCV infection. Current data indicates a less than 50% survival rate at four years post cirrhosis diagnosis. Patients diagnosed with localized resectable hepatocellular carcinoma have a five-year survival rate of 10-30%, whereas those with localized unresectable hepatocellular carcinoma have a five-year survival rate of less than 1%.

To date, there are no effective antiviral agents for treating hepatitis C by suppressing the replication of HCV that are based on the specific interaction with the HCV virus. There is a need for new treatments and therapies for HCV infection. In one aspect, there is provided compounds useful in the treatment or prevention or amelioration of one or more symptoms of hepatitis C. In another aspect, there is provided methods of treatment or prevention or amelioration of one or more symptoms of hepatitis C. In yet another aspect, there is provided methods for modulating the activity of RNA-dependent RNA polymerase (RdRp), particularly the HCV NS5B RNA-dependent RNA polymerase, using the compounds provided herein. In another aspect, there is provided methods of modulating the replication of the HCV genome using the compounds provided herein. REFERENCES

Bartenschager, R., 1997, Molecular targets in inhibition of hepatitis C virus replication, Antivir. Chem. Chemother. 8: 281-301.

Stanley, M. Lemon and Masao Honda, 1997, Internal ribosome entry sites within the RNA genomes of hepatitis C virus and other Flaviviruses, Seminars in Virology 8: 274-288.

Yamada et al., 1996, Genetic organization and diversity of the hepatitis C virus genome, Virology 223:255-281. Lohmann, V. et al., 1997, Biochemical properties of hepatitis C virus NS5B RNA dependent RNA polymerase and identification of amino acid sequence motifs essential for enzymatic activity, / Viral. 71: 8416-8428.

Choo, Q-L, et al., 1989, Isolation of acDNA clone derived from a blood-borne non-A, non-B viral hepatitis genome. Science 244: 359-362. Lohmann, V., F.Komer, J-O. Koch, U. Herian, L. Theilmann, R. Bartenschlarger, 1999,

Replication of subgenomic hepatitis c virus RNAs in a hepatoma cell line. Science 285: 110- 1 13.

Tomei, L et al., Mechanism of Action and Antiviral Actvity of Benzimidazole-Based Allosteric Inhibitors of the Hepatitis C Virus RNA-Dependent RNA Polymerase, Journal of Virology, December 2003, 13225-13231.

McKercher G. et al., Specific inhibitors of HCV polymerase identified using NS5B with lower affinity for template/primer substrate, Nucleic Acids Research, Vol. 32, No. 2, 422-431.

Wang M. et al., Non-nucleoside Analogue Inhibitors Bind to an Allosteric Site on HCV NS5B Polymerase, The Journal of Biochemistry, Vol. 278, No. 11, 9489-9495, 2003. Nguyen, T. T. et al., Resistance Profile of Hepatitis C Virus RNA-Dependent RNA Polymerase Benzothiadiazine Inhibitor, Antimicrobial Agent and Chemotherapy, November 2003, 3525-3530.

Gu, B. et al., Arresting Initiation of Hepatitis C Virus RNA Synthesis Using Heterocyclic Derivatives, The Journal of Biochemistry, Vol. 278, No. 19, 16602-16607, 2003.

The entire disclosure of all references cited in this application are incorporated herein by reference. SUMMARY OF THE INVENTION

In one aspect, the present invention provides non-nucleoside compounds having antiviral activity against HCV that are based on the compound's inhibitory activity of the recombinant HCV RNA-dependent RNA polymerase (RdRp), NS5B. The compounds are found to have minimal toxicity and side effects and yet are highly effective against HCV.

In another aspect, the present invention also provides a novel class of inhibitors of the HCV RdRp, pharmaceutical compositions containing one or more of the compounds, methods of preparing pharmaceutical formulations comprising one or more such compounds, and methods of treatment, prevention or amelioration or one or more of the symptoms of hepatitis C. Also provided are methods of modulating the interaction of an HCV polypeptide with HCV protease. Among the compounds provided herein are compounds that inhibit HCV NS5B RdRp activity. hi another aspect, the present invention further provides for an inhibitor of an HCV NS5B RdRp comprising a non-nucleoside compound or a pharmaceutical composition as disclosed herein.

In yet another aspect, the present invention further provides for an inhibitor of an HCV NS5B RdRp comprising a compound or a pharmaceutical composition as disclosed herein.

The present invention further comprises a method for treating an individual infected with the HCV virus comprising administering an inhibitor of an HCV NS5B RdRp to said individual, the inhibitor comprises a compound or a pharmaceutical composition as disclosed herein.

In one aspect, there is provided a method for treating an individual infected with the HCV virus comprising administering an inhibitor of an HCV NS5B RdRp to the individual, wherein the inhibitor comprises a compound or a pharmaceutical composition as disclosed herein.

In another aspect, there is provided a pharmaceutical composition for treating an individual infected with hepatitis C virus, the pharmaceutical composition comprises an inhibitor of an HCV NS5B RdRp. The present invention further provides for a pharmaceutical composition for treating an individual infected with hepatitis C virus, said pharmaceutical composition comprises of an inhibitor of an HCV NS5B RdRp and a pharmaceutical carrier. DEFINITION The following terms used in the present application have the following definitions unless otherwise indicated:

Alkyl represents both branched and straight chain saturated aliphatic hydrocarbon groups, and may be cyclic or acyclic having the specified number of carbon atoms. For example, means a hydrocarbon that comprise a single carbon two carbon or three carbon atoms, and may include, for example, methyl, ethyl, propyl, isopropyl, butyl and the like.

Alkoxy represents an alkyl group of indicated number of carbon atoms attached to an oxygen atom.

Aryl represents a carbocyclic group having from 6 to 14 carbon atoms and having at least one benzenoid ring, with all available substitutable aromatic carbon atoms of the carbocyclic group being intended as possible points of attachment. Preferred aryl groups include phenyl, 1- naphthyl, 2-naphthyl and indanyl, and especially phenyl and substituted phenyl.

Arylalkyl represents a moiety containing an aryl group bonded to or linked via a lower alkyl. As used herein or unless specified otherwise, lower alkyl represents alkyl groups having 1 to 6 carbons. Alkylaryl represents a moiety containing a lower alkyl bonded to or linked via an aryl group.

Carbonyl group represents a radical group -CO-, which may be further substituted or attached to a variety of different substituents to form different carbonyl groups, including acids, acid halides, aldehydes, esters, carbamates, ketones and the like. Carboxy group represent the radical -CO₂- wherein the carboxy group may be a carboxylic acid group that may also be derivatized or substituted with other functional groups such as carboxy protecting groups.

Cycloalkyl represents a saturated carbocyclic ring having from 3 to 8 carbon atoms, preferably 5 or 6 carbon atoms. Heterocyclic represents, in addition to the heteroaryl groups defined below, saturated and unsaturated cyclic moiety having at least one O, S and/or N atom interrupting a carbocyclic ring structure that consists of one ring or two fused rings, wherein each ring is 5-, 6- or 7-membered and may or may not have double bonds that may be localized or delocalized, which ring structure has from 2 to 8, preferably from 3 to 6 carbon atoms, e.g., 2- or 3-piperidinyl, 2- or 3- piperazinyl, 2- or 3-morpholinyl, or 2- or 3-thiomorpholinyl.

Halogen or halo represents fluorine, chlorine, bromine and iodine. Heteroaryl represents a cyclic moiety having at least one O, S and/or N atom interrupting a carbocyclic ring structure and having a sufficient number of delocalized pi electrons to provide aromatic character, with the aromatic heterocyclyl group having from 2 to 14, preferably 4 or 5 carbon atoms, e.g., 2-, 3- or 4-pyridyl, 2- or 3-furyl, 2- or 3-thienyl, 2-, 4- or 5-thiazolyl, 2- or 4- imidazolyl, 2-, 4- or 5-pyrimidinyl, 2-pyrazinyl, or 3- or 4-pyridazinyl, etc.

In each of the above described groups and those described in the present application, the groups may be unsubstituted or further substituted with 1 , 2, 3 or more substituents as described herein. Non-exclusive substituents include, for example, halo, cyano, nitro, -CF₃, oxo, hydroxy, amino, thio, alkyl, alkoxy, aryl, aryloxy, arylalkyl, heteroaryl, heteroarylalkyl, carbonyl, imino, sulfonyl, sulfinyl and the like.

Other useful terms are described below: Treating means the treatment of existing disease and prophylactic treatment of those at risk of developing the disease.

Capsule refers to a special container or enclosure made of methyl cellulose, polyvinyl alcohols, or denatured gelatins or starch for holding or containing compositions comprising the active ingredients. Hard shell capsules are typically made of blends of relatively high gel strength bone and pork skin gelatins. The capsule itself may contain small amounts of dyes, opaquing agents, plasticizers and preservatives.

Tablet refers to a compressed or molded solid dosage form containing the active ingredients with suitable diluents. The tablet can be prepared by compression of mixtures or granulations obtained by wet granulation, dry granulation or by compaction. Powder for constitution refers to powder blends containing the active ingredients and suitable diluents which can be suspended in water or juices.

Diluent refers to substances that usually make up the major portion of the composition or dosage form Suitable diluents include sugars such as lactose, sucrose, mannitol and sorbitol; starches derived from wheat, corn, rice and potato; and celluloses such as microcrystalline cellulose. The amount of diluent in the composition can range from about 10 to about 90% by weight of the total composition, preferably from about 25 to about 75%, more preferably from about 30 to about 60% by weight, even more preferably from about 12 to about 60%. Disintegrant refers to materials added to the composition to help it break apart (disintegrate) and release the medicaments. Suitable disintegrants include starches; "cold water soluble" modified starches such as sodium carboxymethyl starch; natural and synthetic gums such as locust bean, karaya, guar, tragacanth and agar; cellulose derivatives such as methylcellulose and sodium carboxymethylcellulose; microcrystalline celluloses and cross- linked microcrystalline celluloses such as sodium croscarmellose; alginates such as alginic acid and sodium alginate; clays such as bentonites; and effervescent mixtures. The amount of disintegrant in the composition can range from about 2 to about 15% by weight of the composition, more preferably from about 4 to about 10% by weight.

Binder refers to substances that bind or "glue" powders together and make them cohesive by forming granules, thus serving as the "adhesive" in the formulation. Binders add cohesive strength already available in the diluent or bulking agent. Suitable binders include sugars such as sucrose; starches derived from wheat, corn rice and potato; natural gums such as acacia, gelatin and tragacanth; derivatives of seaweed such as alginic acid, sodium alginate and ammonium calcium alginate; cellulosic materials such as methylcellulose and sodium carboxymethylcellulose and hydroxypropylmethylcellulose; polyvinylpyrrolidone; and inorganics such as magnesium aluminum silicate. The amount of binder in the composition can range from about 2 to about 20% by weight of the composition, more preferably from about 3 to about 10% by weight, even more preferably from about 3 to about 6% by weight.

Lubricant refers to a substance added to the dosage form to enable the tablet, granules, etc. after it has been compressed, to release from the mold or die by reducing friction or wear. Suitable lubricants include metallic stearates such as magnesium stearate, calcium stearate or potassium stearate; stearic acid; high melting point waxes; and water soluble lubricants such as sodium chloride, sodium benzoate, sodium acetate, sodium oleate, polyethylene glycols and d,l- leucine. Lubricants are usually added before compression, since they must be present on the surfaces of the granules and in between them and the parts of the tablet press. The amount of lubricant in the composition can range from about 0.2 to about 5% by weight of the composition, preferably from about 0.5 to about 2%, more preferably from about 0.3 to about 1.5% by weight.

Glident refers to a material that prevents caking and improve the flow characteristics of granulations, so that flow is smooth and uniform. Suitable glidents include silicon dioxide and talc. The amount of glident in the composition can range from about 0.1 to about 5% by weight of the total composition, preferably from about 0.5 to about 2% by weight.

Coloring agents are excipients that provide coloration to the composition or the dosage form. Such excipients can include food grade dyes and food grade dyes adsorbed onto a suitable adsorbent such as clay or aluminum oxide. The amount of the coloring agent can vary from about 0.1 to about 5% by weight of the composition, preferably from about 0.1 to about 1%. Bioavailability refers to the rate and extent to which the active drug ingredient or therapeutic moiety is absorbed into the systemic circulation from an administered dosage form as compared to a standard or control.

Some of the compounds described herein contain one or more asymmetric centers and may thus give rise to diastereomers and optical isomers. The present invention is intended to include such possible diastereomers as well as their racemic and resolved, enantiomerically pure forms and pharmaceutically acceptable salts thereof.

Some of the compounds described herein contain olefinic double bonds, and unless specified otherwise, are meant to include both E and Z geometric isomers. Similarly, tautomers of the compounds are also included in the present invention.

In another aspect, the invention encompasses pharmaceutical compositions for treating HCV or HCV mediated diseases as disclosed herein comprising a pharmaceutically acceptable carrier and a non-toxic therapeutically effective amount of compound of formulae I, II or III as described herein. Depending upon their structure, the compounds of the invention may form pharmaceutically acceptable salts with organic or inorganic acids, or organic or inorganic bases. Examples of suitable acids for such salt formation are hydrochloric, sulfuric, phosphoric, acetic, citric, malonic, salicylic, malic, fumaric, succinic, ascorbic, maleic, methanesulfonic and other mineral and carboxylic acids well known in the art. For formation of salts with bases, suitable bases are, for example, NaOH, KOH, NH₄OH, tetraalkylammonium hydroxide, and the like.

In another aspect, the present invention provides pharmaceutical compositions comprising the inventive compounds as an active ingredient. The pharmaceutical compositions generally additionally comprise a pharmaceutically acceptable carrier diluent, excipient or carrier (collectively referred to herein as carrier materials). Because of their HCV inhibitory activity, such pharmaceutical compositions possess utility in treating hepatitis C and related disorders.

In yet another aspect, the present invention discloses methods for preparing pharmaceutical compositions comprising the inventive compounds as an active ingredient. In the pharmaceutical compositions and methods of the present invention, the active ingredients will typically be administered in admixture with suitable carrier materials suitably selected with respect to the intended form of administration, i.e. oral tablets, capsules (either solid-filled, semisolid filled or liquid filled), powders for constitution, oral gels, elixirs, dispersible granules, syrups, suspensions, and the like, and consistent with conventional pharmaceutical practices. For example, for oral administration in the form of tablets or capsules, the active drug component may be combined with any oral non-toxic pharmaceutically acceptable inert carrier, such as lactose, starch, sucrose, cellulose, magnesium stearate, dicalcium phosphate, calcium sulfate, talc, mannitol, ethyl alcohol (liquid forms) and the like. Moreover, when desired or needed, suitable binders, lubricants, disintegrating agents and coloring agents may also be incorporated in the mixture. Powders and tablets may be comprised of from about 1 to about 95 percent the composition. Suitable binders include starch, gelatin, natural sugars, corn sweeteners, natural and synthetic gums such as acacia, sodium alginate, carboxymethylcellulose, polyethylene glycol and waxes. Among the lubricants there may be mentioned for use in these dosage forms, boric acid, sodium benzoate, sodium acetate, sodium chloride, and the like. Disintegrants include starch, methylcellulose, guar gum and the like.

Sweetening and flavoring agents and preservatives may also be included where appropriate. Some of the terms noted above, namely disintegrants, diluents, lubricants, binders and the like, are discussed in more detail below.

Additionally, the compositions of the present invention may be formulated in sustained release form to provide the rate controlled release of any one or more of the components or active ingredients to optimize the therapeutic effects, i.e. HCV inhibitory activity and the like. Suitable dosage forms for sustained release include layered tablets containing layers of varying disintegration rates or controlled release polymeric matrices impregnated with the active components and shaped in tablet form or capsules containing such impregnated or encapsulated porous polymeric matrices.

Liquid form preparations include solutions, suspensions and emulsions. As an example may be mentioned water or water-prop ylene glycol solutions for parenteral injections or addition of sweeteners and pacifiers for oral solutions, suspensions and emulsions. Liquid form preparations may also include solutions for intranasal administration. Aerosol preparations suitable for inhalation may include solutions and solids in powder form, which may be in combination with a pharmaceutically acceptable carrier such as inert compressed gas, e.g. nitrogen.

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

Also included are solid form preparations which are intended to be converted, shortly before use, to liquid form preparations for either oral or parenteral administration. Such liquid forms include solutions, suspensions and emulsions. The compounds of the invention may also be deliverable transdermally. The transdermal compositions may take the form of creams, lotions, aerosols and/or emulsions and can be included in a transdermal patch of the matrix or reservoir type as are conventional in the art for this purpose. In one aspect, the compound is administered orally, intravenously or subcutaneously.

In another aspect, the pharmaceutical preparation is in a unit dosage form. In such form, the preparation is subdivided into suitably sized unit doses containing appropriate quantities of the active components, e.g., an effective amount to achieve the desired purpose.

The quantity of the active composition of the present invention in a unit dose of preparation may be generally varied or adjusted from about 1.0 mg to about 1,000 mg, preferably from about 1.0 to about 950 mg, more preferably from about 1.0 to about 500 mg, and typically from about 1.0 to about 250 mg, according to the particular application. The actual dosage employed may be varied depending upon the patient's age, sex, weight and severity of the condition being treated. Such techniques are well known in the art. Generally, the human oral dosage form containing the active ingredients can be administered 1 or 2 times per day. The amount and frequency of the administration will be regulated according to the judgment of the attending clinician. A generally recommended daily dosage regimen for oral administration may range from about 1.0 mg to about 1 ,000 mg per day, in single or divided doses. It will be understood, however, that the specific dose level for any particular patient will depend upon a variety of factors including the age, body weight, general health, sex, diet, time of administration, route of administration, rate of excretion, drug combination and the severity of the particular disease undergoing therapy.

Conventional methods for preparing tablets are known. Such methods include dry methods such as direct compression and compression of granulation produced by compaction, or wet methods or other special procedures. Conventional methods for making other forms for administration such as, for example, capsules, suppositories and the like are also well known.

Formulations include those suitable for oral, rectal, nasal, or parenteral (including subcutaneous, intramuscular, intravenous and intradermal) administration. The formulations may conveniently be presented in unit dosage form and may be prepared by any methods well known in the art of pharmacy. See, for example, Gilman, et al. (eds.) (1990) Goodman and Gilman's: The Pharmacological Bases of Therapeutics, 8th Ed., Pergamon Press, Parrytown, N.Y.; Remington's Pharmaceutical Sciences, 17th ed. (1990), Mack Publishing Co., Easton, Pa.; Avis, et al. (eds.) (1993) Pharmaceutical Dosage Forms: Parenteral Medications 2d ed., Dekker, N.Y.; Lieberman, et al. (eds.) (1990) Pharmaceutical Dosage Forms: Tablets 2d ed., Dekker, N.Y.; and Lieberman, et al. (eds.) (1990) Pharmaceutical Dosage Forms: Disperse Systems Dekker, N.Y.

In one aspect, the invention discloses the use of the pharmaceutical compositions disclosed above for treatment of diseases such as, for example, hepatitis C and the like. The method comprises administering a therapeutically effective amount of the inventive pharmaceutical composition to a patient having such a disease or diseases and in need of such a treatment.

In yet another aspect, the compounds of the invention may be used for the treatment of HCV in humans in monotherapy mode or in a combination therapy mode such as, for example, in combination with antiviral agents such as, for example, ribavirin and/or interferon such as, for example, ointerferon and the like.

As noted herein, the present compounds also includes tautomers, rotamers, enantiomers and other stereoisomers of the compounds. Thus, some of the compounds may exist in suitable isomeric forms. Such forms and variations are contemplated to be within the scope of the invention.

Another aspect of the invention provides a method of making the compounds disclosed herein. The compounds may be prepared by several techniques known in the art. Representative illustrative procedures are outlined in the following reaction schemes. It is to be understood that while the following illustrative schemes describe the preparation of a few representative inventive compounds, other related analogs are also contemplated. Such variations are contemplated to be within the scope of the invention.

The present invention provides a method of treating HCV for the prevention and treatment of hepatitis C which comprises administering to a human in need thereof a therapeutically effective amount of a non-nucleoside inhibitor having anti-viral activity against HCV.

In another aspect, the invention provides the use of an antiviral compound in the manufacture of a medicament for the treatment of viral infection, including hepatitis C. REACTION SCHEME:

In one aspect, the preparation of the compounds of the present invention may be performed as shown in the above scheme. A 4,6-dihalo-2-substituted pyrimidine compound, such as the 4,6-dichloro-2-substituted pyrimidine compound exemplified above may be treated with an amine of the formula R_OR₇NH to form a mono-halo or monochloro pyrimidine compound as shown above. Optionally, the compound may be purified or the compound may be used as obtained without further purification. The product may be further treated with a compound of the formula R₃R₄NH to form the tri-substituted pyrimidine as shown above. Depending on the nature of the substituents R₃, R₄, R_& and R₇ the compound may be further derivatized or treated to form their various derivatives as desired. In addition, the various substituents R₃, R₄, Re and R₇ the compound may be protected prior to a reaction and may optionally be deprotected as desired. Application of protecting groups are well known in the art, and are described, for example, in T.W. Greene, Protecting Groups in Organic Synthesis, 3rd edition, John Wiley & Sons, Inc. 1999.

The above reactions may be performed in various organic solvents, including alcohols such as methanol, ethanol, isopropanol, DCM, chloroform, acetonitrile, DMF, acetone, DMSO and the like. Optionally, the reaction may be performed in stoichiometric catalytic ratio of a base relative to the starting material(s). Examples of various bases include organic bases or inorganic bases, or mixtures thereof. Organic bases may include triethylamine, N,N- diisopropylamine, N,N-dimethylaniline, and the like. Typically, the reaction may be performed at ambient temperatures, at 0 to about 25 ⁰C, or at elevated temperatures from about 30 to about 160 ⁰C, as long as necessary to allow the reaction to go to completion. In all cases, the reactions are performed in an inert atmosphere such as in nitrogen or argon. ASPECTS OF THE INVENTION:

The present application discloses compounds, defined further below. In one aspect, there is provided a compound of the formula I:

wherein:

X is CH or N;

Ri is hydrogen or is selected from the group consisting of halo, PeAaIo(C₁ -₆)alkyl, (Ci-₆)alkyl, (C₂-₆)alkenyl, (C₂-₆)alkynyl, amino, cyano, hydroxy, nitro, thio, (C₃.π)cycloalkyl, hetero(C₃-i₂)cycloalkyl, aryl(Ci-io)alkyl, heteroaryl(C|-₃)alkyl, (C^i^bicycloaryl, (C₉-i₂)bicycloheteroaryl, aryl, heteroaryl, (Ci-₆)alkoxy, aryloxy and heteroaryloxy, each of which is further substituted or unsubstituted;

R₂ is hydrogen, or is selected from the group consisting of halo, perhalo(Ci-₆)alkyl, (Ci-₆)alkyl, (C₂-₆)alkenyl, (C₂-₆)alkynyl, amino, cyano, hydroxy, nitro, thio, (C_3-i₂)cycloalkyl, hetero(C₃-i₂)cycloalkyl, aryl(Ci-₆)alkyl, heteroaryl(Ci-₃)alkyl, (C₉-i₂)bicycloaryl, (C₉-i₂)bicycloheteroaryl, aryl, heteroaryl, (Ci-ή)alkoxy, aryloxy, heteroaryloxy, carbonyl group, imino group, sulfonyl group, sulfinyl group and phosphonyl group, each of which is further substituted or unsubstituted;

R₃ and R₄ are each independently hydrogen or are each independently selected from the group consisting of perhalo(Ci-₆)alkyl, (Ci-₆)alkyl, (C₂-₆)alkenyl, (C₂-₆)alkynyl, (C₃.i₂)cycloalkyl, hetero(C₃-i₂)cycloalkyl, aryl(Ci-₆)alkyl, heteroaryl(Ci-₃)alkyl,

(C₉.i₂)bicycloaryl, (C₉.i₂)bicycloheteroaryl, aryl, heteroaryl, (Ci-₆)alkoxy, aryloxy and heteroaryloxy; or wherein R₃ and R₄ are taken together to form a 5, 6 or 7 membered saturated or unsaturated heterocyclic ring, each of which is further substituted or unsubstituted; and

R₅ is selected from the group consisting of halo, perhalo(Cr6)alkyl, (Ci-₆)alkyl, (C₂-₆)alkenyl, (C₂-₆)alkynyl, amino, thio, (C₃_i₂)cycloalkyl, hetero(C₃-i₂)cycloalkyl, aryl(Ci-₆)alkyl, heteroaryl(Ci-₃)alkyl, (Ci-o)alkoxy, aryloxy and heteroaryloxy, each of which is further substituted or unsubstituted; provided that when X is nitrogen, Ri is not amino, R₂ is not hydrogen, and R₅ is not (Ci-₆)alkylthio; or when X is CH, Ri is not amino, R₂ is not carboxyl, and R₅ is not (Ci-6)alkyl; or the pharmaceutically acceptable salts thereof.

In another aspect, there is provided a compound of formula I wherein X is CH or N; Ri is hydrogen or is selected from the group consisting of halo, perhalo(Ci-₆)alkyl, (Ci-₆)alkyl, (C₂-₆)alkenyl, (C₂-₆)alkynyl, amino, thio, (C₃-i₂)cycloalkyl, hetero(C₃-i₂)cycloalkyl, aryl(Ci-io)alkyl, heteroaryl(Ci-₃)alkyl, (C₉-i₂)bicycloaryl, (C_9-12)bicycloheteroaryl, aryl, heteroaryl, (Ci-₆)alkoxy, aryloxy and heteroaryloxy, each of which is further substituted or unsubstituted; R₂ is hydrogen, or is selected from the group consisting of halo, perhalo(Ci-_δ)alkyl, (Ci-_ό)alkyl, (C₂-₆)alkenyl, (C₂-₆)alkynyl, amino, cyano, aryl(Ci-₆)alkyl, heteroaryl(Ci-₃)alkyl, carbonyl group, imino group, sulfonyl group, sulfinyl group and phosphonyl group, each of which is further substituted or unsubstituted; R₃ and R₄ are each independently hydrogen or are each independently selected from the group consisting of (Ci-₆)alkyl, (C_3-i₂)cycloalkyl, hetero(C₃-i₂)cycloalkyl, aryl(Ci-₆)alkyl, heteroaryl(Ci-₃)alkyl, (C₉_i₂)bicycloaryl, (C₉-i₂)bicycloheteroaryl, aryl and heteroaryl; or wherein R3 and R₄ are taken together to form a 5, 6 or 7 membered saturated or unsaturated heterocyclic ring, each of which is further substituted or unsubstituted; and R₅ is selected from the group consisting of (Ci-₃)alkyl in which one carbon atom of the (Ci-3)alkyl can be optionally replaced by a -O-, -S-, or -NH- group, (C₃.]₂)cycloalkyl, hetero(C₃-i₂)cycloalkyl, aryl(Ci-₆)alkyl and heteroaryl(C]-₃)alkyl, each of which is further substituted or unsubstituted.

In one variation of the above compound, X is CH or N; Ri is hydrogen or is selected from the group consisting of amino, thio, (Ci-₆)alkoxy, aryloxy and heteroaryloxy, each of which is further substituted or unsubstituted; R₂ is hydrogen, or is selected from the group consisting of cyano, carbonyl group, imino group, sulfonyl group, sulfinyl group and phosphonyl group, each of which is further substituted or unsubstituted; R3 and R₄ are each independently hydrogen or are each independently selected from the group consisting of (C₉.i₂)bicycloaryl, (C₉.i₂)bicycloheteroaryl, aryl and heteroaryl; or wherein R₃ and R₄ are taken together to form a 5, 6 or 7 membered saturated or unsaturated carbocyclic or heterocyclic ring, each of which is further substituted or unsubstituted; and R₅ is selected from the group consisting of (Ci-₃)alkyl in which one carbon atom of the (C|-₃)alkyl can be optionally replaced by a -O-, -S-, or -NH- group; (C₃-i₂)cycloalkyl, hetero(C3-i₂)cycloalkyl, aryl(Ci-₆)alkyl and heteroaryl (C i-₃)alkyl; each of which is unsubstituted or substituted with hydroxy, (Ci-3)alkoxy, or amino.

In another aspect, there is provided a compound of the formula II:

II wherein: R₃ and R₄ are each independently hydrogen or are each independently selected from the group consisting of perhalo(Ci-₆)alkyl, (Cι-₆)alkyl, (C₂-₆)alkenyl, (C₂-_ό)alkynyl, (C₃-i₂)cycloalkyl, hetero(C₃-i₂)cycloalkyl, aryl(Ci-₆)alkyl, heteroaryl(Ci-₃)alkyl, (C₉.]₂)bicycloaryl, (C₉-i₂)bicycloheteroaryl, aryl, heteroaryl, (Ci-₆)alkoxy, aryloxy and heteroaryloxy; or wherein R₃ and R₄ are taken together to form a 5, 6 or 7 membered saturated or unsaturated carbocyclic or heterocyclic ring, each of which is further substituted or unsubstituted; R₅ is selected from the group consisting of (Ci-₃)alkyl in which one carbon atom of the (Ci-₃)alkyl can be optionally replaced by a -O-, -S-, or -NH- group; (C_3-i₂)cycloalkyl, hetero(C₃-)₂)cycloalkyl, aryl(Ci-₆)alkyl and heteroaryl(Ci-₃)alkyl; each of which is unsubstituted or substituted with hydroxy, (Ci-3)alkoxy, or amino; and R$ and R₇ are each independently hydrogen or are each independently selected from the group consisting of (C₃-i₂)cycloalkyl, hetero(C₃-i₂)cycloalkyl, aryl(Ci-i_O)alkyl, heteroaryl(Ci-₃)alkyl, (C₉-i₂)bicycloaryl, (C9-)₂)bicycloheteroaryl, aryl and heteroaryl, each of which is further substituted or unsubstituted; provided that when R₅ is CH₃S-, then R₃ and R₄ are not taken together to form a piperazinyl group, R₆ is not hydrogen, and R₇ is not 4-morpholino-phenyl-; or the pharmaceutically acceptable salts thereof. hi one variation of the above compound, R₃ and R₄ are each independently selected from the group consisting of perhalo(C]-₆)alkyl, (Ci-₆)alkyl, (C₂-₆)alkenyl, (C₂-₆)alkynyl, (C₃.i₂)cycloalkyl, hetero(C₃-i₂)cycloalkyl, aryl(Ci-₆)alkyl, heteroaryl(Ci-₃)alkyl,

(C₉_i₂)bicycloaryl, (Cg.^bicycloheteroaryl, aryl, heteroaryl, (Ci-₆)alkoxy, aryloxy and heteroaryloxy; or wherein R₃ and R₄ are taken together to form a 5, 6 or 7 membered saturated or unsaturated heterocyclic ring, each of which is further substituted or unsubstituted. In another variation of the above, R₃ and R₄ are taken together to form a 5, 6 or 7 membered saturated or unsaturated heterocyclic ring, each of which is unsusbtituted or further substituted with 1 , 2 or 3 substituents selected from the group consisting of perhalo(Cι-₆)alkyl, (Ci-₆)alkyl, (C₂-₆)alkenyl, (C₂-₆)alkynyl, amino, cyano, hydroxy, nitro, thio, (C_3-i₂)cycloalkyl, hetero(C₃-i₂)cycloalkyl, aryl(Ci-₆)alkyl, heteroaryl(Ci-₃)alkyl, (C₉.i₂)bicycloaryl, (C₉.i₂)bicycloheteroaryl, aryl, heteroaryl, (Ci-₆)alkoxy, aryloxy, heteroaryloxy, sulfonyl group, sulfinyl group and carbonyl group.

In a particular variation of the above compound, the heterocyclic ring is selected from the group consisting of tetrahydrofuranyl, tetrahydropyranyl, morpholinyl, piperidinyl, piperazinyl, dihydropyridinyl, 2,2-dimethyl-l,3-dioxolane, N-methylpiperidin-3-yl, N-methylpyrrolidin-3-yl, pyrrolidinyl, thiomoφholinyl, thiomoφholino-1 -oxide, thiomoφholino- 1,1 -dioxide, 4- ethyloxycarbonylpiperazinyl, 3-oxopiperazinyl, 2-imidazolidonyl, 2-pyrrolidinonyl, 2- oxohomopiperazinyl and tetrahydropyrimidin-2-one, each of which is unsubstituted or substituted with 1, 2 or 3 substituents selected from the group consisting of perhalo(Ci-₆)alkyl, (Ci-₆)alkyl, (C₂-₆)alkenyl, (C₂-₆)alkynyl, amino, cyano, hydroxy, nitro, thio, (C_3-12)cycloalkyl, hetero(C₃-]₂)cycloalkyl, aryl(Ci-6)alkyl, heteroaryl(Ci-₃)alkyl,

(C₉-i₂)bicycloheteroaryl, aryl, heteroaryl, (Ci-₆)alkoxy, aryloxy, heteroaryloxy, sulfonyl group, sulfinyl group and carbonyl group. In one variation of the above compound, the heterocyclic ring is selected from the group consisting of moφholinyl, 4-(Ri₀SO)piperazinyl, 4-

(RioS0₂)piperazinyl and 4-(RioCO)piperazinyl, and wherein Ri₀ is selected from the group consisting of

(C₉_i₂)bicycloheteroaryl, aryl and heteroaryl, each of which is unsubstituted or substituted with 1 , 2 or 3 substituents selected from the group consisting of perhalo(Ci-₆)alkyl, (C]-₆)alkyl, (C₂-₆)alkenyl, (C₂-₆)alkynyl, amino, cyano, hydroxy, nitro and thio. In another variation of the above, Rio is a heteroaryl selected from the group consisting of pyrrole, furan, thiophene, imidazole, oxazole, thiazole, pyrazole, pyridine, pyrimidine, quinoline, isoquinoline, purine, triazole, tetrazole, triazine, and carbazole, each of which is unsubstituted or substituted with 1, 2 or 3 substituents selected from the group consisting of perhalo(Ci-₆)alkyl, (Ci-₆)alkyl, (C₂-₆)alkenyl, (C₂-₆)alkynyl, amino, cyano, hydroxy, nitro and thio. In one particular variation of the above compound, Rio is a heteroaryl selected from the group consisting of pyridine, pyrimidine and quinoline, each of which is unsubstituted or substituted with 1, 2 or 3 substituents selected from the group consisting of perhalo(Ci-₆)alkyl, (Ci-₆)alkyl, (C₂-₆)alkenyl, (C₂-ό)alkynyl, amino, cyano, hydroxy, nitro and thio. In each of the above variations comprising the variables R₆ and R₇, R^ and R₇ are each independently hydrogen or are each independently selected from the group consisting of (C_3-] ₂)cycloalkyl, hetero(C₃-i₂)cycloalkyl, aryl(Ci-io)alkyl, heteroaryl(Ci-₃)alkyl,

(C₉.₁₂)bicycloheteroaryl, aryl and heteroaryl, each of which is further substituted or unsubstituted. In another variation of the above, R₆ is hydrogen and R₇ is selected from the group consisting of (C₃.]₂)cycloalkyl, aryl(Ci-io)alkyl, (C₉-i₂)bicycloaryl, and aryl each of which is further substituted or unsubstituted with 1, 2 or 3 substituents selected from the group consisting of perhalo(Ci-₆)alkyl, (Ci-₆)alkyl, (C₂-_ό)alkenyl, (C₂-₆)alkynyl, amino, cyano, hydroxy, nitro and thio. In yet another variation, R₇ is phenyl or naphthyl, each unsubstituted or further substituted with NRuRi₂, wherein each Rn and R_]2 are each independently hydrogen, or are independently selected from the group consisting of perhalo(Ci-₆)alkyl, (Ci-₆)alkyl, (C₂-₆)alkenyl, (C₂-₆)alkynyl, (C₃.i₂)cycloalkyl, hetero(C₃-i₂)cycloalkyl, aryl(Ci-₆)alkyl, heteroaryl(Ci-3)alkyl, (C₉-i₂)bicycloaryl,

aryl, heteroaryl, (Ci-_δ)alkoxy, aryloxy and heteroaryloxy; or wherein Ru and Ri₂ are taken together to form a 5, 6 or 7 membered saturated or unsaturated heterocyclic ring, each of which is further substituted or unsubstituted.

In another variation of the above compounds, R₇ is phenyl or naphthyl, each unsubstituted or further substituted with NR₁₁Ri₂, wherein Ri i and Ri₂ are taken together to form a 5, 6 or 7 membered saturated or unsaturated heterocyclic ring, each of which is further substituted or unsubstituted. hi one particular variation, R] i and Ri₂ are taken together to form a heterocyclic ring, wherein the heterocyclic ring is selected from the group consisting of tetrahydrofuranyl, tetrahydropyranyl, morpholinyl, piperidinyl, piperazinyl, dihydropyridinyl, 2,2-dimethyl-l,3-dioxolane, N-methylpiperidin-3-yl, N-methylpyrrolidin-3-yl, pyrrolidinyl, thiomorpholinyl, thiomorpho lino- 1 -oxide, thiomorpholino- 1,1 -dioxide, 4- ethyloxycarbonylpiperazinyl, 3-oxopiperazinyl, 2-imidazolidonyl, 2-pyrrolidinonyl, 2- oxohomopiperazinyl and tetrahydropyrimidin-2-one, each of which is unsubstituted or substituted with 1, 2 or 3 substituents selected from the group consisting of perhalo(Ci-₆)alkyl, (Ci-₆)alkyl, (C₂-₆)alkenyl, (C₂-_ό)alkynyl, amino, cyano, hydroxy, nitro, thio, (C₃-i₂)cycloalkyl, hetero(C₃-i₂)cycloalkyl, aryl(Ci-_δ)alkyl, heteroaryl(Ci-₃)alkyl, (Cc_1-12)bicycloaryl, (Cc,.i₂)bicycloheteroaryl, aryl, heteroaryl, (Ci-_ό)alkoxy, aryloxy, heteroaryloxy, sulfonyl group, sulfinyl group and carbonyl group.

In a particular variation of the above compounds, Rn and Rn are taken together to form a heterocyclic ring, wherein the heterocyclic ring is selected from the group consisting of morpholinyl, piperidinyl, piperazinyl and dihydropyridinyl, each unsubstituted or substituted with a substituent selected from the group consisting of perhalo(Ci-₆)alkyl, (Ci-₆)alkyl, (C₂-₆)alkenyl, (C₂-6)alkynyl, amino, cyano, hydroxy, nitro and thio. In another aspect, there is provided a compound of the formula III:

III wherein:

Ri is hydrogen or is selected from the group consisting of halo, perhalo(Cι-₆)alkyl, (Ci-₆)alkyl, (C₂-₆)alkenyl, (C₂-₆)alkynyl, amino, cyano, hydroxy, nitro, thio, (C₃-i₂)cycloalkyl, hetero(C₃-i₂)cycloalkyl, aryl(Ci-]o)alkyl, heteroaryl(Ci-₃)alkyl, (C₉.i₂)bicycloaryl, (C₉-i₂)bicycloheteroaryl, aryl, heteroaryl, (Ci-_ό)alkoxy, aryloxy and heteroaryloxy, each of which is further substituted or unsubstituted;

R₂ is hydrogen, or is selected from the group consisting of halo, perhalo(Ci-₆)alkyl, (Ci-6)alkyl, (C₂-₆)alkenyl, (C₂-₆)alkynyl, amino, cyano, hydroxy, nitro, thio, (C₃-i₂)cycloalkyl, hetero(C₃-i₂)cycloalkyl, aryl(Ci-₆)alkyl, heteroaryl(Ci-₃)alkyl, (C₉-i₂)bicycloaryl, (C₉-i₂)bicycloheteroaryl, aryl, heteroaryl, (Ci-₆)alkoxy, aryloxy, heteroaryloxy, carbonyl group, imino group, sulfonyl group, sulfinyl group and phosphonyl group, each of which is further substituted or unsubstituted; R₃ and R₄ are each independently hydrogen or are each independently selected from the group consisting of perhalo(Ci-₆)alkyl, (Ci-₆)alkyl, (C₂-₆)alkenyl, (C₂-₆)alkynyl, (C₃-i₂)cycloalkyl, hetero(C₃-i₂)cycloalkyl, aryl(Ci-₆)alkyl, heteroaryl(Ci-₃)alkyl, (C₉_i₂)bicycloaryl, (C₉-i₂)bicycloheteroaryl, aryl, heteroaryl, (Ci-_δ)alkoxy, aryloxy and heteroaryloxy; or wherein R₃ and R₄ are taken together to form a 5, 6 or 7 membered saturated or unsaturated heterocyclic ring, each of which is further substituted or unsubstituted; and

R₅ is selected from the group consisting of halo, perhalo(Ci-₆)alkyl, (Ci-₆)alkyl, (C₂-₆)alkenyl, (C₂-₆)alkynyl, amino, thio, (C₃.i₂)cycloalkyl, hetero(C₃-i₂)cycloalkyl, aryl(Ci-₆)alkyl, heteroaryl(Ci-₃)alkyl, (Ci-β)alkoxy, aryloxy and heteroaryloxy, each of which is further substituted or unsubstituted; provided that when Ri is hydrogen, R₂ is carboxyl, R₃ is hydrogen and R₄ is 4-N- morpholinophenyl, then R₅ is not methyl; or the pharmaceutically acceptable salts thereof. In one variation of the above compounds, R₁ is hydrogen or is selected from the group consisting of halo, perhalo(Ci-₆)alkyl, (Ci-₆)alkyl, (C₂-₆)alkenyl, (C₂-_ό)alkynyl, amino, thio, (C₃-i₂)cycloalkyl, hetero(C₃-i₂)cycloalkyl, aryl(Ci-i_O)alkyl, heteroaryl(Ci-₃)alkyl, (C₉-i₂)bicycloaryl, (C^^bicycloheteroaryl, aryl, heteroaryl, (Ci-₆)alkoxy, aryloxy and heteroaryloxy, each of which is further substituted or unsubstituted; R₂ is hydrogen, or is selected from the group consisting of halo, perhalo(Ci-6)alkyl, (Ci-_δ)alkyl, (C₂-₆)alkenyl, (C₂-₆)alkynyl, amino, cyano, aryl(Ci-_δ)alkyl, heteroaryl(Ci-₃)alkyl, carbonyl group, imino group, sulfonyl group, sulfinyl group and phosphonyl group, each of which is further substituted or unsubstituted; R₃ and R₄ are each independently hydrogen or are each independently selected from the group consisting of (Ci-₆)alkyl, (C₃_i₂)cycloalkyl, hetero(C₃-i₂)cycloalkyl, aryl(Ci-₆)alkyl, heteroaryl(Ci-₃)alkyl,

aryl and heteroaryl; or wherein R₃ and R₄ are taken together to form a 5, 6 or 7 membered saturated or unsaturated heterocyclic ring, each of which is further substituted or unsubstituted; and R5 is selected from the group consisting of (Ci-₃)alkyl in which one carbon atom of the (Ci-₃)alkyl can be optionally replaced by a -O-, -S-, or -NH- group, (C₃-i₂)cycloalkyl, hetero(C₃-i₂)cycloalkyl, aryl(C]-₆)alkyl and heteroaryl(Ci-₃)alkyl, each of which is further substituted or unsubstituted.

In another variation of the above, Ri is hydrogen or is selected from the group consisting of amino, thio, (Ci-₆)alkoxy, aryloxy and heteroaryloxy, each of which is further substituted or unsubstituted; R₂ is hydrogen, or is selected from the group consisting of cyano, carbonyl group, imino group, sulfonyl group, sulfinyl group and phosphonyl group, each of which is further substituted or unsubstituted; R₃ and R₄ are each independently hydrogen or are each independently selected from the group consisting of (Cg.i₂)bicycloaryl, (C₉-i₂)bicycloheteroaryl, aryl and heteroaryl; or wherein R₃ and R₄ are taken together to form a 5, 6 or 7 membered saturated or unsaturated carbocyclic or heterocyclic ring, each of which is further substituted or unsubstituted; and R₅ is selected from the group consisting of (C)-₃)alkyl in which one carbon atom of the (Ci-₃)alkyl can be optionally replaced by a -O-, -S-, or -NH- group; (C₃.i₂)cycloalkyl, hetero(C₃-i₂)cycloalkyl, aryl(Ci-₆)alkyl and heteroaryl(Ci-₃)alkyl; each of which is unsubstituted or substituted with hydroxy, (Ci-₃)alkoxy, or amino. In particular variations of the above, wherein R₂ is selected from the group consisting of cyano, carbonyl group, imino group, sulfonyl group, sulfinyl group and phosphonyl group, each of which is further substituted or unsubstituted. Also, in yet another particular variation, R₂ is selected from the group consisting of -COOH, -SO3H and -PO₃H, or the pharmaceutically acceptable salts thereof. In yet another variation of the above, Ri is -NR]₃Ri₄ wherein Ri₃ and R_H are each independently hydrogen or are each independently selected from the group consisting of (C₃-i₂)cycloalkyl, hetero(C₃-i₂)cycloalkyl, aryl(Ci-io)alkyl, heteroaryl(Ci-3)alkyl, (C₉-i₂)bicycloaryl,

aryl and heteroaryl, each of which is further substituted or unsubstituted.

In particular variations of the above compounds, R₁₃ is hydrogen and R_]4 is selected from the group consisting of (C_3-i₂)cycloalkyl, aryl(Ci-io)alkyl,

and aryl each of which is further substituted or unsubstituted with 1 , 2 or 3 substituents selected from the group consisting of perhalo(Ci-₆)alkyl, (Ci-₆)alkyl, (C₂-₆)alkenyl, (C₂-₆)alkynyl, amino, cyano, hydroxy, nitro and thio. In another particular variation, R₁₄ is phenyl or naphthyl, each unsubstituted or further substituted with NRi₅R₁₆, wherein each R₁5 and Ri₆ are each independently hydrogen, or are independently selected from the group consisting of perhalo(Ci-₆)alkyl, (Ci-₆)alkyl, (C₂-₆)alkenyl, (C₂-₆)alkynyl, (C_3-i₂)cycloalkyl, hetero(C3-i₂)cycloalkyl, aryl(Ci-6)alkyl, heteroaryl(Ci-3)alkyl,

(C₉-i₂)bicycloheteroaryl, aryl, heteroaryl, (Ci-_δ)alkoxy, aryloxy and heteroaryloxy; or wherein Ri ₁ and Ri ₂ are taken together to form a 5, 6 or 7 membered saturated or unsaturated heterocyclic ring, each of which is further substituted or unsubstituted. In yet another variation of the above compounds, Ri₄ is phenyl or naphthyl, each unsubstituted or further substituted with NR₁₅R₁₆, wherein R₁₅ and Ri₆ are taken together to form a 5, 6 or 7 membered saturated or unsaturated heterocyclic ring, each of which is further substituted or unsubstituted.

In another variation of the above compounds, Ri ₅ and Ri 6 are taken together to form a heterocyclic ring, wherein the heterocyclic ring is selected from the group consisting of tetrahydrofuranyl, tetrahydropyranyl, morpholinyl, piperidinyl, piperazinyl, dihydropyridinyl, 2,2-dimethyl-l,3-dioxolane, N-methylpiperidin-3-yl, N-methylpyrrolidin-3-yl, pyrrolidinyl, thiomorpholinyl, thiomorpholino-1 -oxide, thiomorpholino- 1,1 -dioxide, 4- ethyloxycarbonylpiperazinyl, 3-oxopiperazinyl, 2-imidazolidonyl, 2-pyrrolidinonyl, 2- oxohomopiperazinyl and tetrahydropyrimidin-2-one, each of which is unsubstituted or substituted with 1, 2 or 3 substituents selected from the group consisting of perhalo(Ci-₆)alkyl, (Ci-₆)alkyl, (C₂-₆)alkenyl, (C₂-₆)alkynyl, amino, cyano, hydroxy, nitro, thio, (C_3-i₂)cycloalkyl, hetero(C₃-i₂)cycloalkyl, aryl(Ci-6)alkyl, heteroaryl(Ci-₃)alkyl,

(Cg.i₂)bicycloheteroaryl, aryl, heteroaryl, (C]-₆)alkoxy, aryloxy, heteroaryloxy, sulfonyl group, sulfinyl group and carbonyl group.

In another variation of the above compounds, R₁₅ and Ri ₆ are taken together to form a heterocyclic ring, wherein the heterocyclic ring is selected from the group consisting of morpholinyl, piperidinyl, piperazinyl and dihydropyridinyl, each unsubstituted or substituted with a substituent selected from the group consisting of perhalo(Ci-₆)alkyl, (Ci-₆)alkyl, (C₂-₆)alkenyl, (C₂-₆)alkynyl, amino, cyano, hydroxy, nitro and thio. In a particular variation of the above compounds, R₂ is hydrogen.

According to each of the above variations, R₅ is selected from the group consisting of halo, perhalo(Ci-₆)alkyl, (Ci-₆)alkyl, (C₂-_δ)alkenyl, (C₂-₆)alkynyl, amino, thio, (C₃-i₂)cycloalkyl, hetero(C3-i₂)cycloalkyl, aryl(Ci-₆)alkyl, heteroaryl(Ci-3)alkyl, (Ci-₆)alkoxy, aryloxy and heteroaryloxy, each of which is further substituted or unsubstituted. Further, according to each of the above variations, R₅ is selected from the group consisting of perhalo(Ci-₆)alkyl, (Ci-₆)alkyl, (C₂-₆)alkenyl, (C₂-₆)alkynyl, amino and thio, each unsusbtituted or further substituted. Also, according to each of the above compounds, R₅ is selected from the group consisting of (Ci-₃)alkyl in which one carbon atom of the (Ci-₃)alkyl can be optionally replaced by a -O-, -S-, or -NH- group; each (C]-₃)alkyl unsubstituted or further substituted with a substituent selected from the group consisting of perhalo(Ci-₃)alkyl, (Ci-3)alkyl, (C₂-β)alkenyl, (C₂-₆)alkynyl, amino, cyano, hydroxy, nitro and thio. In yet another variation of each of the above compounds, R₅ is selected from the group consisting of (Ci-₃)alkyl, (Ci-₃)alkylthio, or (Ci-₃)alkoxy.

Also provided in the present application are the following non-exclusive compounds: {4- [6-(4-Diethylamino-phenylamino)-2-ethylsulfanyl-pyrimidin-4-yl]-piperazin-l-yl}-phenyl- methanone; {4-[6-(4-Diethylamino-phenylamino)-2-ethylsulfanyl-pyrimidin-4-yl]-piperazin-l- yl}-pyridin-4-yl-methanone; {4-[6-(4-Diethylamino-phenylamino)-2-ethylsulfanyl-pyrimidin-4- yl] -piperazin- 1 -yl } -(2-methyl-pyridin-4-yl)-methanone; {4-[6-(4-Diethylamino-phenylamino)-2- ethylsulfanyl-pyrimidin-4-yl]-piperazin- 1 -yl } -(pyrimidin-2-yl)-methanone; {4- [6-(4- Diethylamino-phenylamino)-2-ethylsulfanyl-pyrimidin-4-yl]-piperazin-l-yl}-(5-methyl- pyrimidin-2-yl)-methanone; {4-[2-Benzylsulfanyl-6-(4-diethylamino-phenylammo)-pyrimidin- 4-yl]-piperazin-l-yl}-pyridin-4-yl-methanone; {4-[2-Butylsulfanyl-6-(4-diethylamino- phenylamino)-pyrimidin-4-yl]-piperazin-l-yl}-pyridin-4-yl-methanone; {4-[2-Butylsulfanyl-6- (4-diethylamino-phenylamino)-pyrimidin-4-yl]-piperazin-l-yl}-pyrimidin-2-yl-methanone; {4- [6-(4-Diethylamino-phenyl)-methyl-amino]-2-ethylsulfanyl-pyrimidin-4-yl} -piperazin- 1-yl}- pheπyl-methanone; {4-[6-(4-Dimethylamino-phenyl)-methyl-amino]-2-ethylsulfanyl-pyrimidin- 4-yl} -piperazin- 1 -yl} -phenyl-methanone; [4-(6- {[4-(Benzyl-methyl-amino)-phenyl]-methyl- amino} -2-ethylsulfanyl-pyrimidin-4-yl)-piperazin-l-yl]-phenyl-methanone; (4- (6-[(4- Diethylamino-phenyl)-methyl-amino]-2-ethyl-pyrimidin-4-yl}-piperazin-l-yl)-phenyl- methanone; 6-(Ethyl-2-(4-morpholin-4-yl-phenylamino)-nicotinic acid ethyl ester; 6-(Ethyl-2- (4-morpholin-4-yl-phenylamino)-nicotinic acid butyl ester; 6-(Ethyl-2-(4-morpholin-4-yl- phenylamino)-nicotinic acid benzyl ester; 6-(n-Butyl-2-(4-moφholin-4-yl-phenylamino)- nicotinic acid butyl ester; 6-Butyl-2-[methyl-(4-moφholin-4-yl-phenyl)amino]-nicotinic acid butyl ester; 6-Butyl-2-[(4-morpholin-4-yl-phenyl)-propyl-amino]-nicotinic acid butyl ester; 6- Butyl-2-(4-piperazin-l-yl-phenylamino)-nicotinic acid; and 6-Butyl-2-{methyl-[4-(4-methyl- piperazin-l-yl)-phenyl]-amino}-nicotinic acid. According to each of the above compounds, the compound may be in the form of a pharmaceutically acceptable salt. In a particular variation of the above compounds, the compound is present as a single isomer or a mixture of stereoisomers, or tautomers.

In another aspect, there is provided a pharmaceutical composition comprising, as an active ingredient, a compound according to any one of the above compounds. In one variation, the composition is a solid or a liquid adapted for oral administration. In another aspect, there is provided a method of inhibiting HCV comprising contacting HVC with any of the above compounds. In another aspect, there is provided a method of inhibiting HCV comprising contacting any one of the above compounds in a subject in order to inhibit HCV in vivo. In yet another aspect, there is provided a compound exhibiting HCV protease inhibitory activity, wherein the compound is selected from any of the above aompounds. In yet another aspect, there is provided a method of treating liver disease in a patient comprising administering to the patient a therapeutically effective amount of a compound or pharmaceutical composition noted above.

In another aspect, there is provided the use of a compound or a composition as defined in each of the above aspects and variations, or a pharmaceutically acceptable salt, prodrug or solvate thereof, for preparing a medicament for use in the treatment of liver diseases.

EXPERMENTAL:

The following exemplary compounds of the Invention are prepared and assayed for activity:

II

10: {4-[6-(4-Diethylamino-phenylamino)-2-ethylsulfanyl-pyrimidin-4-yl]-piperazin-l- yl}-phenyl-methanone 20: {4-[6-(4-Diethylamino-phenylamino)-2-ethylsulfanyl-pyrimidin-4-yl]-piperazin-l- yl } -pyridin-4-yl-methanone

30: {4-[6-(4-Diethylamino-phenylamino)-2-ethylsulfanyl-pyrimidin-4-yl]-piperazin-l- yl}-(2-methyl-pyridin-4-yl)-methanone 40: {4-[6-(4-Diethylamino-phenylamino)-2-ethylsulfanyl-pyrimidin-4-yl]-piperazin-l- yl } -(pyrimidin-2-yl)-methanone

50: {4-[6-(4-Diethylamino-phenylamino)-2-ethylsulfanyl-pyrimidin-4-yl]-piperazin-l- yl}-(5-methyl-ρyrimidin-2-yl)-methanone

60: {4-[2-Benzylsulfanyl-6-(4-diethylamino-phenylamino)-pyrimidin-4-yl]-piperazin-l- yl} -pyridin-4-yl-methanone

70: {4-[2-Butylsulfanyl-6-(4-diethylamino-phenylamino)-pyrimidin-4-yl]-piperazin-l- yl } -pyridin-4-yl-methanone

80: {4-[2-Butylsulfanyl-6-(4-diethylamino-phenylamino)-pyrimidin-4-yl]-piperazin-l- yl} -pyrimidin-2-yl-methanone 90: {4-[6-(4-Diethylammo-phenyl)-methyl-amino]-2-ethylsulfanyl-pyrimidin-4-yl}- piperazin- 1 -yl} -phenyl-methanone

100: {4-[6-(4-Dimethylamino-phenyl)-methyl-amino]-2-ethylsulfanyl-pyrimidin-4-yl}- piperazin- 1 -yl} -phenyl-methanone

110:[4-(6-{[4-(Benzyl-methyl-amino)-phenyl]-methyl-amino}-2-ethylsulfanyl- pyrimidin-4-yl)-piperazin-l-yl]-phenyl-methanone

120:(4-{6-[(4-Diethylamino-phenyl)-methyl-amino]-2-ethyl-pyrimidin-4-yl}-piperazin- 1 -yl)-phenyl-methanone

III

130: 6-(Ethyl-2-(4-morpholin-4-yl-phenylamino)-nicotinic acid ethyl ester 140: 6-(Ethyl-2-(4-morpholin-4-yl-phenylamino)-nicotinic acid butyl ester 150: 6-(Ethyl-2-(4-morpholin-4-yl-phenylamino)-nicotinic acid benzyl ester 160: 6-(n-Butyl-2-(4-morpholin-4-yl-phenylamino)-nicotinic acid butyl ester

170: 6-Butyl-2-[methyl-(4-moφholin-4-yl-phenyl)amino]-nicotinic acid butyl ester 180: 6-Butyl-2-[(4-moφholin-4-yl-phenyl)-propyl-amino]-nicotinic acid butyl ester 190: 6-Butyl-2-(4-piperazin- 1 -yl-phenylamino)-nicotinic acid

200: 6-Butyl-2-{methyl-[4-(4-methyl-piperazin-l-yl)-phenyl]-amino}-nicotinic acid. The above compounds are named using CS ChemDraw Ultra, Version 6.0. The compounds may be prepared as described above employing standard chemical synthetic methods known in the art, and the resulting products are characterized using standard nmr, IR, melting points, and mass spectrometry. Spectroscopic identification and characterization of the compounds suggest that the compounds have the desired and consistent structures shown in the Table above.

Assay for HCV RdRp Inhibitory Activity:

Test of inhibitory effect on activity of HCV RNA Polymerase (RNA dependent RNA polymerase, NS 5B) in vitro: The following in vitro experiments are conducted to examine the inhibitory effect of the compounds according to the present invention on the activity of HCV RNA dependent RNA Polymerase. Other assays may be employed as is known in the art, and non-exclusive representative assays for determining the inhibitory effects of the compounds are cited herein. Construct of recombinant HCV RNA polymerase. The HCV RNA polymerase is prepared as follows:

HCV cDNA is obtained from the blood of HCV-Ib type HCV patient and the NS5B region (1773 bps) is amplified by PCR and cloned into pVLHIS, a baculo virus transfer vector, to prepare a recombinant transfer vector. The prepared transfer vector and the wild-type AcNPV vector are co-transfected into Sf 9 insect cell line to yield a recombinant baculovirus containing the histidine-tagged recombinant vectorpVLHIS-NS5B. Sufficiently cultured insect cells are infected with the resulting recombinant baculovirus and cultured in Grace's medium containing 10% FBS for 3 to 4 days. The culture broth is centrifuged to obtain only the infected cells. The cells are washed three times with PBS and resuspended in binding buffer [50 mM Na-phosphate (pH 8.0), 30 mM NaCl, 10 mM imidazole, 1 mM DTT, 10 % glycerol, 1 % NP-40], sonicated and the clearized lysate is obtained. Recombinant NS5B is purified by affinity column chromatography using a Ni-NTA His bind resin (Novagen) to produce pure NS5B protein. The (His)₆-tagged NS5B is bound to Ni-NTA resin and washed the binding buffer containing 50 mM imidazole. The bound NS5B is eluted with the binding buffer containing imidazole in a step- gradient manner (100-300 mM). The NS5B protein fractions are dialyzed against buffer [50 mM Tris-HCl, 50 mM NaCl, 1 mM DTT, 5 mg MgCl₂, 10 % glycerol], followed by at -70 ⁰C in a small aliquot.

Construct of RNA template containing HCV 3' end (3'-UTR)

The RNA template containing HCV 3' end (3'-UTR) is prepared as follows: The 3'-UTR cDNA (220 bp) of HCV is obtained from Ib HCV RNA of the blood of a hepatitis C patient by PCR and cloned into pcDNA3 vector. Linearized DNA fragment containing the 3'-UTR is prepared using the restriction enzyme Eco RI and used as a template for in vitro transcription using T7 RNA polymerase to prepare RNA fragment containing 3 '- UTR. Measurement of inhibitory activity of compounds of the present invention on recombinant HCV RNA polymerase in vitro. In vitro inhibitory activity of the compounds of the present invention on recombinant HCV RNA polymerase is measured as follows:

A streptavidin-coated well plate is prepared suitable for the sample to be examined. 25 μ\ of 2X assay buffer [50 mM Tris-Cl (pH 7.5), 100 mM NaCl, 10 mM MgCl₂, 20 mM KCl, 1 mM EDTA, 1 mM DTT] and 10 μl of purified HCV RNA polymerase 200 ng and 3'-UTR template RNA are added to each well. 5 μl of the sample to be examined is added to have final concentrations of 10, 1, 0.1 and 0.01 μg/mL. Finally, 10 μl of a reactant solution containing DIG- (digoxigenin)-UTP, biotin-UTP, ATP, CTP, GTP, and UTP as a nucleotide for the polymerase reaction with the RNA template of HCV 3'-UTR RNA is added to each well. The reaction mixture is incubated at 22 ⁰C for 60 minutes. By the action of HCV polymerase, newly generated RNAs including UTP conjugated with biotin and DIG are copied and these new RNAs could bind to streptavidin coated on the well by biotin-conjugated UTP. After completion of the reaction, the plate is washed three times with 200 μl of a washing buffer (pH 7.0, Roche) to remove unreacted substances and impurities.

100 μ\ of the secondary antibody anti -DIG-POD (peroxidase, Roche) is added to each well and incubated at 37 °C for 1 hour. The plate is washed with the washing buffer. Finally, 100 μl of ABTS® (Roche) as a POD substrate is added to each well and reacted for 15 to 30 minutes. The optical density (OD) is measured using an ELISA reader (Biot-Tek Instrument) at 405 run. The inhibitory effect on the activity of HCV polymerase is calculated by substracting the OD of the positive control without the sample.

The compounds of the present invention shows inhibitory activity of HCV RNA polymerase at about 93 to 99% at 10 μg/mL; about 60 to 80 % at 1 μg/mL; about 30 to 55 % at 0.1 μg/mL; about 15 to 30 % at 0.01 μg/mL. The results obtained demonstrates that the compounds of the present invention show excellent inhibitory effects on activity of HCV RNA polymerase which plays an important role in reproduction of HCV, thereby inhibiting replication of HCV by this property. Also, the compounds according to the present invention can be advantageously used as a therapeutic or prophylactic agent of C type hepatitis. Cytotoxicity assay

The cytotoxicity of the compounds of formula I, II and III is examined by the MTT assay, a well established in vitro toxicology assay methods, using Hep G2 cells. All the compounds used in the experiment are found to have CC₅₀ of greater than 100 μg/mL, indicating that the compounds have extremely low cytotoxicity. Spectrophotometry Assay:

In one aspect of the invention, the assays of compounds comprising carboxyl groups may also be performed as described below:

Spectrophotometric assay for the HCV serine protease is performed on the compounds of the present invention by following the procedure described by R. Zhang et al., Analytical Biochemistry, 270 (1999) 268-275, the disclosure of which is incorporated herein by reference. The assay based on the proteolysis of chromogenic ester substrates is suitable for the continuous monitoring of HCV NS3 protease activity. Presented below are the synthesis, characterization and application of these novel spectrophotometric compounds, including ester substrates to high throughput screening and detailed kinetic evaluation of HCV NS 3 protease inhibitors. Materials and Methods:

Materials: Chemical reagents for assay related buffers are obtained from Sigma Chemical Company (St. Louis, Mo.). UV7VIS Spectrometer model LAMBDA 12 is from Perkin Elmer (Norwalk, Conn.) and 96-well UV plates are obtained from Corning (Corning, N. Y.). The prewarming block is from USA Scientific (Ocala, FIa.) and the 96-well plate vortex er is from Labline Instruments (Melrose Park, 111.). A Spectramax Plus microtiter plate reader with monochrometer is obtained from Molecular Devices (Sunnyvale, Calif.). Enzyme Preparation:

Recombinant heterodimeric HCV NS3/NS4A protease (strain Ia) is prepared by using the procedures published previously (D. L. SaIi et al, Biochemistry, 37 (1998) 3392-3401). Protein concentrations are determined by the Biorad dye method using recombinant HCV protease standards previously quantified by amino acid analysis. Prior to assay initiation, the enzyme storage buffer (50 mM sodium phosphate pH 8.0, 300 mM NaCl, 10% glycerol, 0.05% lauryl maltoside and 10 mM DTT) is exchanged for the assay buffer (25 mM MOPS pH 6.5, 300 mM NaCl, 10% glycerol, 0.05% lauryl maltoside, 5 μM EDTA and 5 μM DTT) utilizing a Biorad Bio-Spin P-6 prepacked column. Spectra of Substrates and Products:

Spectra of substrates and the corresponding chromophore products are obtained in the pH 6.5 assay buffer. Extinction coefficients are determined at the optimal off-peak wavelength in 1- cm cuvettes (340 nm for 3-Np and HMC, 370 nm for PAP and 400 nm for 4-Np) using multiple dilutions. The optimal off-peak wavelength is defined as that wavelength yielding the maximum fractional difference in absorbance between substrate and product (product OD- substrate OD)/substrate OD). Protease Assay: HCV protease assays are performed at 30 ⁰C using a 200 μl reaction mix in a 96-well microtiter plate. Assay buffer conditions (25 mM MOPS pH 6.5, 300 mM NaCl, 10% glycerol, 0.05% lauryl maltoside, 5 μM EDTA and 5 μM DTT) are optimized for the NS3/NS4A heterodimer (D. L. SaIi et al., ibid.)). Typically, 150 μl mixtures of buffer, substrate and inhibitor are placed in wells (final concentration of DMSO 4% v/v) and allowed to preincubate at 30 ⁰C for approximately 3 minutes. Fifty μl of prewarmed protease (12 nM, 30 ⁰C) in assay buffer, is then used to initiate the reaction (final volume 200 μl). The plates are monitored over the length of the assay (60 minutes) for change in absorbance at the appropriate wavelength (340 nm for 3-Np and HMC, 370 nm for PAP, and 400 nm for 4-Np) using a Spectromax Plus microtiter plate reader equipped with a monochrometer (acceptable results can be obtained with plate readers that utilize cutoff filters). Proteolytic cleavage of the ester linkage between the Nva and the chromophore is monitored at the appropriate wavelength against a no enzyme blank as a control for non-enzymatic hydrolysis. The evaluation of substrate kinetic parameters is performed over a 30-fold substrate concentration range (about 6-200 μM). Initial velocities are determined using linear regression and kinetic constants are obtained by fitting the data to the Michaelis-Menten equation using non-linear regression analysis (Mac Curve Fit 1.1, K. Raner). Turnover numbers (kc_at) are calculated assuming the enzyme is fully active. Evaluation of Inhibitors and Inactivators:

The inhibition constants (Kj) for the competitive inhibitors are determined experimentally at fixed concentrations of enzyme and substrate by plotting V₀ /v, vs. inhibitor concentration ([I]₀) according to the rearranged Michaelis-Menten equation for competitive inhibition kinetics: V₀ / V₁ =1+[I]_O /(Kj (1+[S]₀ /K_m)), where V₀ is the uninhibited initial velocity, Vj is the initial velocity in the presence of inhibitor at any given inhibitor concentration ([I]₀) and [S]_o is the substrate concentration used. The resulting data are fitted using linear regression and the resulting slope, 1/(Kj (1+[S]₀ /K_n,), is used to calculate the Ki value.

The obtained K; values for the various compounds of the present invention are given in the Tables. From these test results, it would be apparent to the skilled artisan that the compounds of the invention have excellent utility as NS3-serine protease inhibitors.

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

Claims

What is claimed:

1. A compound of the formula I:

wherein: X is CH or N;

Ri is hydrogen or is selected from the group consisting of halo, perhalo(Ci-₆)alkyl, (Ci-ό)alkyl, (C₂-₆)alkenyl, (C2-ό)alkynyl, amino, cyano, hydroxy, nitro, thio, (C3-i2)cycloalkyl, hetero(C₃-i₂)cycloalkyl, aryl(C]-i_O)alkyl, heteroaryl(Ci-₃)alkyl, (C₉-i₂)bicycloaryl, (C₉-i₂)bicycloheteroaryl, aryl, heteroaryl, (Ci-₆)alkoxy, aryloxy and heteroaryloxy, each of which is further substituted or unsubstituted;

R-₂ is hydrogen, or is selected from the group consisting of halo, perhalo(Cj-6)alkyl, (Ci-ή)alkyl, (C₂-₆)alkenyl, (C₂-₆)alkynyl, amino, cyano, hydroxy, nitro, thio, (C₃-i₂)cycloalkyl, hetero(C₃-i₂)cycloalkyl, aryl(Ci-₆)alkyl, heteroaryl(Ci-₃)alkyl, (Cζ>.i₂)bicycloaryl, (C₉-i₂)bicycloheteroaryl, aryl, heteroaryl, (Cι-₆)alkoxy, aryloxy, heteroaryloxy, carbonyl group, imino group, sulfonyl group, sulfϊnyl group and phosphonyl group, each of which is further substituted or unsubstituted;

R.3 and R₄ are each independently hydrogen or are each independently selected from the group consisting of perhalo(Ci-6)alkyl, (Ci-₆)alkyl, (C₂-₆)alkenyl, (C₂-₆)alkynyl, (C₃.i₂)cycloalkyl, hetero(C₃-i₂)cycloalkyl, aryl(Ci-₆)alkyl, heteroaryl(Ci-₃)alkyl, (C<).i₂)bicycloaryl, (C₉-i₂)bicycloheteroaryl, aryl, heteroaryl, (Ci-₆)alkoxy, aryloxy and heteroaryloxy; or wherein R₃ and R₄ are taken together to form a 5, 6 or 7 membered saturated or unsaturated heterocyclic ring, each of which is further substituted or unsubstituted; and

R5 is selected from the group consisting of halo, perhalo(Ci-6)alkyl, (Ci-6)alkyl, (C₂-₆)alkenyl, (C₂-_ό)alkynyl, amino, thio, (C₃_i₂)cycloalkyl, hetero(C₃-i₂)cycloalkyl, aryl(Ci-₆)alkyl, heteroaryl(Ci-₃)alkyl, (Ci-_ό)alkoxy, aryloxy and heteroaryloxy, each of which is further substituted or unsubstituted; provided that when X is nitrogen, R| is not amino, R₂ is not hydrogen, and R₅ is not (Ci-_δ)alkylthio; or when X is CH, Ri is not amino, R₂ is not carboxyl, and R₅ is not (Ci-₆)alkyl; or the pharmaceutically acceptable salts thereof.

2. The compound of claim 1 , wherein: X is CH or N;

Ri is hydrogen or is selected from the group consisting of halo, perhalo(Ci-6)alkyl, (Ci-₆)alkyl, (C₂-₆)alkenyl, (C₂-₆)alkynyl, amino, thio, (C₃.i₂)cycloalkyl, hetero(C₃-i₂)cycloalkyl, aryl(Ci-io)alkyl, heteroaryl(Ci-₃)alkyl, (Cg.^bicycloaryl, (Cg.^bicycloheteroaryl, aryl, heteroaryl, (Ci-₆)alkoxy, aryloxy and heteroaryloxy, each of which is further substituted or unsubstituted;

R₂ is hydrogen, or is selected from the group consisting of halo, perhalo(Ci-₆)alkyl, (Ci-₆)alkyl, (C₂-₆)alkenyl, (C₂-₆)alkynyl, amino, cyano, aryl(Ci-₆)alkyl, heteroaryl(Ci-₃)alkyl, carbonyl group, imino group, sulfonyl group, sulfinyl group and phosphonyl group, each of which is further substituted or unsubstituted; R₃ and R₄ are each independently hydrogen or are each independently selected from the group consisting of (Ci-6)alkyl, (C_3-i₂)cycloalkyl, hetero(C₃-i₂)cycloalkyl, aryl(Ci-₆)alkyl, heteroaryl(Ci-₃)alkyl, (C₉_i₂)bicycloaryl, (C₉-i₂)bicycloheteroaryl, aryl and heteroaryl; or wherein R₃ and R₄ are taken together to form a 5, 6 or 7 membered saturated or unsaturated heterocyclic ring, each of which is further substituted or unsubstituted; and R₅ is selected from the group consisting of (Ci-₃)alkyl in which one carbon atom of the

(Ci-₃)alkyl can be optionally replaced by a -O-, -S-, or -NH- group, (C₃-i₂)cycloalkyl, hetero(C₃-i₂)cycloalkyl, aryl(Ci-₆)alkyl and heteroaryl(Ci-₃)alkyl, each of which is further substituted or unsubstituted.

3. The compound of claim 2, wherein: X is CH or N;

Ri is hydrogen or is selected from the group consisting of amino, thio, (Ci-₆)alkoxy, aryloxy and heteroaryloxy, each of which is further substituted or unsubstituted;

R₂ is hydrogen, or is selected from the group consisting of cyano, carbonyl group, imino group, sulfonyl group, sulfinyl group and phosphonyl group, each of which is further substituted or unsubstituted;

R₃ and R₄ are each independently hydrogen or are each independently selected from the group consisting of (C9-i₂)bicycloaryl, (C₉-i₂)bicycloheteroaryl, aryl and heteroaryl; or wherein R₃ and R₄ are taken together to form a 5, 6 or 7 membered saturated or unsaturated carbocyclic or heterocyclic ring, each of which is further substituted or unsubstituted; and R₅ is selected from the group consisting of (Ci-₃)alkyl in which one carbon atom of the (Ci-₃)alkyl can be optionally replaced by a -O-, -S-, or -NH- group; (Cs_-12)CyClOaIlCyI, hetero(C₃-₁₂)cycloalkyl, aryl(Ci-₆)alkyl and heteroaryl(Ci-₃)alkyl; each of which is unsubstituted or substituted with hydroxy, (C]-₃)alkoxy, or amino.

4. A compound of the formula II:

π wherein:

R₃ and R₄ are each independently hydrogen or are each independently selected from the group consisting of perhalo(Ci-₆)alkyl, (Ci-₆)alkyl, (C₂-₆)alkenyl, (C₂-₆)alkynyl, (C_3-12)cycloalkyl, hetero(C₃-i₂)cycloalkyl, aryl(Ci-₆)alkyl, heteroaryl(Ci-₃)alkyl,

(C₉-i₂)bicycloaryl, (C₉-i₂)bicycloheteroaryl, aryl, heteroaryl, (Ci-_ό)alkoxy, aryloxy and heteroaryloxy; or wherein R₃ and R₄ are taken together to form a 5, 6 or 7 membered saturated or unsaturated carbocyclic or heterocyclic ring, each of which is further substituted or unsubstituted; R₅ is selected from the group consisting of (C]-₃)alkyl in which one carbon atom of the

(Ci-₃)alkyl can be optionally replaced by a -O-, -S-, or -NH- group; (C_3-] ₂)cycloalkyl, hetero(C₃-₁₂)cycloalkyl, aryl(Ci-₆)alkyl and heteroaryl(Ci-₃)alkyl; each of which is unsubstituted or substituted with hydroxy, (Ci-₃)alkoxy, or amino; and

R₆ and R₇ are each independently hydrogen or are each independently selected from the group consisting of (C₃-i₂)cycloalkyl, hetero(C₃-i₂)cycloalkyl, aryl(Crio)alkyl, heteroaryl(Ci-₃)alkyl, (Cc_1-12)bicycloaryl,

aryl and heteroaryl, each of which is further substituted or unsubstituted; provided that when R₅ is CH₃S-, then R₃ and R₄ are not taken together to form a piperazinyl group, R_O is not hydrogen, and R₇ is not 4-morpholino-phenyl-; or the pharmaceutically acceptable salts thereof.

5. The compound of claim 4, wherein R₃ and R₄ are each independently selected from the group consisting of perhalo(Ci-6)alkyl, (Ci-6)alkyl, (C₂-6)alkenyl, (C₂-₆)alkynyl, (C₃-i₂)cycloalkyl, hetero(C₃-i₂)cycloalkyl, ETyI(C₁-_O)EIlCyI, heteroaryl(Ci-₃)alkyl, (Cg-i₂)bicycloaryl,

aryl, heteroaryl, (Cr₆)alkoxy, aryloxy and heteroaryloxy; or wherein R₃ and R₄ are taken together to form a 5, 6 or 7 membered saturated or unsaturated heterocyclic ring, each of which is further substituted or unsubstituted. 6. The compound of claim 5, wherein R₃ and R₄ are taken together to form a 5,

6 or 7 membered saturated or unsaturated heterocyclic ring, each of which is unsusbtituted or further substituted with 1, 2 or 3 substituents selected from the group consisting of perhalo(Ci-₆)alkyl, (Ci-₆)alkyl, (C₂-₆)alkenyl, (C₂-₆)alkynyl, amino, cyano, hydroxy, nitro, thio, (C_3-i₂)cycloalkyl, hetero(C₃-₁₂)cycloalkyl, aryl(Ci-6)alkyl, heteroaryl(C₁-3)alkyl,

(C_9-i₂)bicycloheteroaryl, aryl, heteroaryl, (Ci-₆)alkoxy, aryloxy, heteroaryloxy, sulfonyl group, sulfinyl group and carbonyl group.

7. The compound of claim 6, wherein the heterocyclic ring is selected from the group consisting of tetrahydrofuranyl, tetrahydropyranyl, morpholinyl, piperidinyl, piperazinyl, dihydropyridinyl, 2,2-dimethyl-l,3-dioxolane, N-methylpiperidin-3-yl, N-methylpyrrolidin-3-yl, pyrrolidinyl, thiomorpholinyl, thiomorpholino-1 -oxide, thiomorpholino- 1,1 -dioxide, 4- ethyloxycarbonylpiperazinyl, 3-oxopiperazinyl, 2-imidazolidonyl, 2-pyrrolidinonyl, 2- oxohomopiperazinyl and tetrahydropyrimidin-2-one, each of which is unsubstituted or substituted with 1, 2 or 3 substituents selected from the group consisting of perhalo(d-₆)alkyl, (Ci-₆)alkyl, (C₂-_ό)alkenyl, (C₂-6)alkynyl, amino, cyano, hydroxy, nitro, thio, (C₃-i₂)cycloalkyl, hetero(C₃-i₂)cycloalkyl, aryl(Ci-₆)alkyl, heteroaryl(Ci-₃)alkyl, (C₉_i₂)bicycloaryl,

(C₉-i₂)bicycloheteroaryl, aryl, heteroaryl, (Ci-₆)alkoxy, aryloxy, heteroaryloxy, sulfonyl group, sulfinyl group and carbonyl group.

8. The compound of claim 7, wherein the heterocyclic ring is selected from the group consisting of morpholinyl, 4-(RioSO)piperazinyl, 4-(RioS0₂)piperazinyl and A- (RioCO)piperazinyl, and wherein Ri₀ is selected from the group consisting of (Cc>-i₂)bicycloaryl,

aryl and heteroaryl, each of which is unsubstituted or substituted with 1, 2 or 3 substituents selected from the group consisting of perhalo(C]-₆)alkyl, (Ci-₆)alkyl, (C₂-₆)alkenyl, (C₂-₆)alkynyl, amino, cyano, hydroxy, nitro and thio.

9. The compound of claim 8, wherein Rio is a heteroaryl selected from the group consisting of pyrrole, furan, thiophene, imidazole, oxazole, thiazole, pyrazole, pyridine, pyrimidine, quinoline, isoquinoline, purine, triazole, tetrazole, triazine, and carbazole, each of which is unsubstituted or substituted with 1 , 2 or 3 substituents selected from the group consisting of perhalo(Ci-₆)alkyl, (Ci-_δ)alkyl, (C₂-_ό)alkenyl, (C₂-₆)alkynyl, amino, cyano, hydroxy, nitro and thio.

10. The compound of claim 9, wherein Ri₀ is a heteroaryl selected from the group consisting of pyridine, pyrimidine and quinoline, each of which is unsubstituted or substituted with 1, 2 or 3 substituents selected from the group consisting of perhalo(Ci-₆)alkyl, (Ci-₆)alkyl, (C₂-₆)alkenyl, (C₂-₆)alkynyl, amino, cyano, hydroxy, nitro and thio.

11. The compound of any one of claims 4 to 10, wherein R₆ and R₇ are each independently hydrogen or are each independently selected from the group consisting of (C₃.i₂)cycloalkyl, hetero(C₃-i₂)cycloalkyl, aryl(Ci-io)alkyl, heteroaryl(d-₃)alkyl,

(C₉-i₂)bicycloheteroaryl, aryl and heteroaryl, each of which is further substituted or unsubstituted.

12. The compound of any one of claims 4 to 11, wherein R₆ is hydrogen and R₇ is selected from the group consisting of (C₃-i₂)cycloalkyl, aryl(Ci-₁₀)alkyl,

and aryl each of which is further substituted or unsubstituted with 1, 2 or 3 substituents selected from the group consisting of perhalo(C]-₆)alkyl, (C]-₆)alkyl, (C₂-₆)alkenyl, (C₂-₆)alkynyl, amino, cyano, hydroxy, nitro and thio.

13. The compound any one of claims 4 to 12, wherein R₇ is phenyl or naphthyl, each unsubstituted or further substituted with NRn Ri 2, wherein each Rn and R]₂ are each independently hydrogen, or are independently selected from the group consisting of perhalo(Ci-₆)alkyl. (Ci-₆)alkyl, (C₂-₆)alkenyl, (C₂-₆)alkynyl, (C_3-i₂)cycloalkyl, hetero(C₃-i₂)cycloalkyl, aryl(Ci-₆)alkyl, heteroaryl(Ci-₃)alkyl, (Cc_1-12)bicycloaryl, (C₉-i₂)bicycloheteroaryl, aryl, heteroaryl, (C^alkoxy, aryloxy and heteroaryloxy; or wherein Ri ₁ and R₎₂ are taken together to form a 5, 6 or 7 membered saturated or unsaturated heterocyclic ring, each of which is further substituted or unsubstituted.

14. The compound any one of claims 4 to 13, wherein R₇ is phenyl or naphthyl, each unsubstituted or further substituted with NRnR]₂, wherein Rn and Ri₂ are taken together to form a 5, 6 or 7 membered saturated or unsaturated heterocyclic ring, each of which is further substituted or unsubstituted.

15. The compound of any one of claims 4 to 14, wherein R) _t and Ri₂ are taken together to form a heterocyclic ring, wherein the heterocyclic ring is selected from the group consisting of tetrahydrofuranyl, tetrahydropyranyl, morpholinyl, piperidinyl, piperazinyl, dihydropyridinyl, 2,2-dimethyl-l,3-dioxolane, N-methylpiperidin-3-yl, N-methylpyrrolidin-3-yl, pyrrolidinyl, thiomorpholinyl, thiomorpholino-1 -oxide, thiomorpholino- 1 ,1 -dioxide, A- ethyloxycarbonylpiperazinyl, 3-oxopiperazinyl, 2-imidazolidonyl, 2-pyrrolidinonyl, 2- oxohomopiperazinyl and tetrahydropyrimidin-2-one, each of which is unsubstituted or substituted with 1, 2 or 3 substituents selected from the group consisting of perhalo(Ci-₆)alkyl, (Ci-₆)alkyl, (C₂-₆)alkenyl, (C₂-_δ)alkynyl, amino, cyano, hydroxy, nitro, thio, (C_3-12)cycloalkyl, hetero(C₃-i₂)cycloalkyl, aryl(Ci-₆)alkyl, heteroaryl(C]-₃)alkyl, (C₉-i₂)bicycloaryl, (C₉-i₂)bicycloheteroaryl, aryl, heteroaryl, (Ci-₆)alkoxy, aryloxy, heteroaryloxy, sulfonyl group, sulfinyl group and carbonyl group.

16. The compound of any one of claims 4 to 15, wherein Rn and Ri₂ are taken together to form a heterocyclic ring, wherein the heterocyclic ring is selected from the group consisting of morpholinyl, piperidinyl, piperazinyl and dihydropyridinyl, each unsubstituted or substituted with a substituent selected from the group consisting of perhalo(Ci-₆)alkyl, (Ci-₆)alkyl, (C₂-₆)alkenyl, (C₂-₆)alkynyl, amino, cyano, hydroxy, nitro and thio.

17. A compound of the formula III:

III wherein:

Ri is hydrogen or is selected from the group consisting of halo, perhak^Q -₆)alkyl,

(Ci-₆)alkyl, (C₂-6)alkenyl, (C₂-6)alkynyl, amino, cyano, hydroxy, nitro, thio, (C_3-12)cycloalkyl, hetero(C₃-i₂)cycloalkyl, aryl(C]-io)alkyl, heteroaryl(Ci-₃)alkyl, (Cp_-12)bicycloaryl,

(Cc_1-12)bicycloheteroaryl, aryl, heteroaryl, (Ci-₆)alkoxy, aryloxy and heteroaryloxy, each of which is further substituted or unsubstituted;

R₂ is hydrogen, or is selected from the group consisting of halo, perhalo(Ci-₆)alkyl,

(Ci-₆)alkyl, (C₂-₆)alkenyl, (C₂-₆)alkynyl, amino, cyano, hydroxy, nitro, thio, (C_3-12)cycloalkyl, hetero(C₃-i₂)cycloalkyl, aryl(C]-₆)alkyl, heteroaryl(Ci-₃)alkyl, (C<>-i₂)bicycloaryl,

(C₉.i₂)bicycloheteroaryl, aryl, heteroaryl, (Ci-6)alkoxy, aryloxy, heteroaryloxy, carbonyl group, imino group, sulfonyl group, sulfinyl group and phosphonyl group, each of which is further substituted or unsubstituted;

R₃ and R₄ are each independently hydrogen or are each independently selected from the group consisting of perhalo(Ci-₆)alkyl, (Ci-₆)alkyl, (C₂-₆)alkenyl, (C₂-₆)alkynyl,

(C₃-i₂)cycloalkyl, hetero(C₃-i₂)cycloalkyl, aryl(Ci-₆)alkyl, heteroaryl(Ci-₃)alkyl,

(CQ.i₂)bicycloaryl,

aryl, heteroaryl, (Ci-₆)alkoxy, aryloxy and heteroaryloxy; or wherein R₃ and R₄ are taken together to form a 5, 6 or 7 membered saturated or unsaturated heterocyclic ring, each of which is further substituted or unsubstituted; and

R₅ is selected from the group consisting of halo, perhalo(Ci-₆)alkyl, (Ci-_δ)alkyl, (C₂-_ό)alkenyl, (C₂-₆)alkynyl, amino, thio, (C₃-i₂)cycloalkyl, hetero(C₃-i₂)cycloalkyl, aryl(Ci-6)alkyl, heteroaryl(Ci-3)alkyl, (Ci-₆)alkoxy, aryloxy and heteroaryloxy, each of which is further substituted or unsubstituted; provided that when R_\ is hydrogen, R₂ is carboxyl, R₃ is hydrogen and R₄ is 4-N- morpholinophenyl, then R₅ is not methyl; or the pharmaceutically acceptable salts thereof.

18. The compound of any one of claim 1 to 3 or claim 17, wherein:

R] is hydrogen or is selected from the group consisting of halo, perhalo(Ci-₆)alkyl, (Ci-6)alkyl, (C₂-6)alkenyl, (C2-ό)alkynyl, amino, thio, (C3-i₂)cycloalkyl, hetero(C3-i₂)cycloalkyl, aryl(Ci-io)alkyl, heteroaryl(Ci-₃)alkyl, (C₉-₁₂)bicycloaryl, (C₉_i₂)bicycloheteroaryl, aryl, heteroaryl, (C^alkoxy, aryloxy and heteroaryloxy, each of which is further substituted or unsubstituted;

R₂ is hydrogen, or is selected from the group consisting of halo, perhalo(Ci-₆)alkyl, (Ci-₆)alkyl, (C₂-₆)alkenyl, (C₂-_ό)alkynyl, amino, cyano, aryl(Ci-₆)alkyl, heteroaryl(C]-₃)alkyl, carbonyl group, imino group, sulfonyl group, sulfinyl group and phosphonyl group, each of which is further substituted or unsubstituted; R₃ and R₄ are each independently hydrogen or are each independently selected from the group consisting of (Ci-6)alkyl, (C3_i₂)cycloalkyl, hetero(C3-i₂)cycloalkyl, aryl(Ci-6)alkyl, heteroaryl(Ci-₃)alkyl,

aryl and heteroaryl; or wherein R₃ and R₄ are taken together to form a 5, 6 or 7 membered saturated or unsaturated heterocyclic ring, each of which is further substituted or unsubstituted; and R₅ is selected from the group consisting of (Ci-₃)alkyl in which one carbon atom of the

(Ci-₃)alkyl can be optionally replaced by a -O-, -S-, or -NH- group, (C₃_i₂)cycloalkyl, hetero(C₃-i₂)cycloalkyl, aryl(C_r6)alkyl and heteroaryl(Ci-₃)alkyl, each of which is further substituted or unsubstituted.

19. The compound of any one of claim 17 or 18, wherein: Ri is hydrogen or is selected from the group consisting of amino, thio, (Ci-₆)alkoxy, aryloxy and heteroaryloxy, each of which is further substituted or unsubstituted;

R₂ is hydrogen, or is selected from the group consisting of cyano, carbonyl group, imino group, sulfonyl group, sulfinyl group and phosphonyl group, each of which is further substituted or unsubstituted; R₃ and R₄ are each independently hydrogen or are each independently selected from the group consisting of (Cς^bicycloaryl, (C^^bicycloheteroaryl, aryl and heteroaryl; or wherein R₃ and R₄ are taken together to form a 5, 6 or 7 membered saturated or unsaturated carbocyclic or heterocyclic ring, each of which is further substituted or unsubstituted; and R₅ is selected from the group consisting of (Ci-₃)alkyl in which one carbon atom of the

(Ci-₃)alkyl can be optionally replaced by a -O-, -S-, or -NH- group; (C₃.]₂)cycloalkyl, hetero(C₃-]₂)cycloalkyl, aryl(Ci-₆)alkyl and heteroaryl(Ci-₃)alkyl; each of which is unsubstituted or substituted with hydroxy, (Ci-₃)alkoxy, or amino.

20. The compound of any one of claims 17 to 19, wherein R₂ is selected from the group consisting of cyano, carbonyl group, imino group, sulfonyl group, sulfinyl group and phosphonyl group, each of which is further substituted or unsubstituted.

21. The compound of any one of claims 17 to 19, wherein R₂ is selected from the group consisting of -COOH, -SO₃H and -PO₃H, or the pharmaceutically acceptable salts thereof.

22. The compound of any one of claims 17 to 21, wherein Ri is -NR₁₃R₁₄ wherein Ri₃ and R_H are each independently hydrogen or are each independently selected from the group consisting of (C_3-i₂)cycloalkyl, hetero(C₃-i₂)cycloalkyl, aryl(Ci-io)alkyl, heteroaryl(Ci-₃)alkyl, (C₉_i₂)bicycloaryl, (C9_i₂)bicycloheteroaryl, aryl and heteroaryl, each of which is further substituted or unsubstituted.

23. The compound of any one of claims 17 to 22, wherein R] ₃ is hydrogen and Ri₄ is selected from the group consisting of (C_3-12)cycloalkyl, aryl(Ci-io)alkyl, (C₉-i₂)bicycloaryl, and aryl each of which is further substituted or unsubstituted with 1, 2 or 3 substituents selected from the group consisting of perhalo(Ci-₆)alkyl, (Ci-₆)alkyl, (C₂-₆)alkenyl, (C₂-_δ)alkynyl, amino, cyano, hydroxy, nitro and thio.

24. The compound any one of claims 17 to 23, wherein Ru is phenyl or naphthyl, each unsubstituted or further substituted with NR₁₅R₁₆, wherein each R₁₅ and R₁₆ are each independently hydrogen, or are independently selected from the group consisting of perhalo(Ci-₆)alkyl, (Ci-₆)alkyl, (C₂-₆)alkenyl, (C₂-₆)alkynyl, (C_3-i₂)cycloalkyl, hetero(C₃-i₂)cycloalkyl, aryl(Ci-₆)alkyl, heteroaryl(Ci-₃)alkyl, (C₉-i₂)bicycloaryl, (C₉.]₂)bicycloheteroaryl, aryl, heteroaryl, (Ci-₆)alkoxy, aryloxy and heteroaryloxy; or wherein Ri ₁ and Ri ₂ are taken together to form a 5, 6 or 7 membered saturated or unsaturated heterocyclic ring, each of which is further substituted or unsubstituted.

25. The compound any one of claims 17 to 24, wherein R)₄ is phenyl or naphthyl, each unsubstituted or further substituted with NR₁5R₁6, wherein R₎₅ and Ri₆ are taken together to form a 5, 6 or 7 membered saturated or unsaturated heterocyclic ring, each of which is further substituted or unsubstituted.

26. The compound of any one of claims 17 to 25, wherein Ri₅ and Ri₆ are taken together to form a heterocyclic ring, wherein the heterocyclic ring is selected from the group consisting of tetrahydrofuranyl, tetrahydropyranyl, morpholinyl, piperidinyl, piperazinyl, dihydropyridinyl, 2,2-dimethyl-l,3-dioxolane, N-methylpiperidin-3-yl, N-methylpyrrolidin-3-yl, pyrrolidinyl, thiomorpholinyl, thiomorpholino-1 -oxide, thiomorpholino- 1,1 -dioxide, 4- ethyloxycarbonylpiperazinyl, 3-oxopiperazinyl, 2-imidazolidonyl, 2-pyrrolidinonyl, 2- oxohomopiperazinyl and tetrahydropyrimidin-2-one, each of which is unsubstituted or substituted with 1, 2 or 3 substituents selected from the group consisting of perhalo(Ci-₆)alkyl, (Ci-₆)alkyl, (C₂-₆)alkenyl, (C₂-₆)alkynyl, amino, cyano, hydroxy, nitro, thio, (C₃.i₂)cycloalkyl, hetero(C₃-i₂)cycloalkyl, aryl(Ci-₆)alkyl, heteroaryl(Ci-₃)alkyl, (C₉_i₂)bicycloaryl, (C₉-i₂)bicycloheteroaryl, aryl, heteroaryl, (Ci-₆)alkoxy, aryloxy, heteroaryloxy, sulfonyl group, sulfinyl group and carbonyl group.

27. The compound of any one of claims 17 to 26, wherein Ri ₅ and Rj ₅ are taken together to form a heterocyclic ring, wherein the heterocyclic ring is selected from the group consisting of morpholinyl, piperidinyl, piperazinyl and dihydropyridinyl, each unsubstituted or substituted with a substituent selected from the group consisting of perhalo(C|-6)alkyl, (Ci-6)alkyl, (C₂-₆)alkenyl, (C₂-₆)alkynyl, amino, cyano, hydroxy, nitro and thio.

28. The compound of any one of claims 1 to 3, and 17 to 27, wherein R₂ is hydrogen.

29. The compound of any one of claims 1 to 28, wherein R₅ is selected from the group consisting of halo, perhalo(Ci-₆)alkyl, (Ci-₆)alkyl, (C₂-₆)alkenyl, (C₂-₆)alkynyl, amino, thio, (C₃_i₂)cycloalkyl, hetero(C₃-i₂)cycloalkyl, aryl(Ci-₆)alkyl, heteroaryl(Ci-₃)alkyl, (Ci-₆)alkoxy, aryloxy and heteroaryloxy, each of which is further substituted or unsubstituted.

30. The compound of any one of claims 1 to 29, wherein R₅ is selected from the group consisting of perhalo(Ci-₆)alkyl, (Ci-₆)alkyl, (C₂-₆)alkenyl, (C₂-_ό)alkynyl, amino and thio, each unsusbtituted or further substituted.

31. The compound of any one of claims 1 to 30, wherein R₅ is selected from the group consisting of (C]-₃)alkyl in which one carbon atom of the (Ci-₃)alkyl can be optionally replaced by a -O-, -S-, or -NH- group; each (Ci-3)alkyl unsubstituted or further substituted with a substituent selected from the group consisting of perhalo(Ci-₃)alkyl, (Ci-₃)alkyl, (C₂-₆)alkenyl, (C₂-₆)alkynyl, amino, cyano, hydroxy, nitro and thio.

32. The compound of any one of claims 1 to 31, wherein R₅ is selected from the group consisting of (Ci-₃)alkyl, (Ci-₃)alkylthio, or (Ci-₃)alkoxy.

33. A compound selected from the group consisting of:

{4-[6-(4-Diethylamino-phenylamino)-2-ethylsulfanyl-pyrimidin-4-yl]-piperazin-l-yl}- phenyl-methanone;

{4-[6-(4-Diethylamino-phenylamino)-2-ethylsulfanyl-pyrimidin-4-yl]-piperazin-l-yl}- pyridin-4-yl-methanone;

{4-[6-(4-Diemylamino-phenylamino)-2-ethylsulfanyl-pyrimidin-4-yl]-piperazin-l-yl}- (2-methyl-pyridin-4-yl)-methanone;

{4-[6-(4-Diethylamino-phenylamino)-2-ethylsulfanyl-pyrimidin-4-yl]-piperazin-l-yl}- (pyrimidin-2-yl)-methanone; {4-[6-(4-Diethylamino-phenylamino)-2-ethylsulfanyl-pyrimidin-4-yl]-piperazin-l-yl}-

(5-methyl-pyrimidin-2-yl)-methanone;

{4-[2-Benzylsulfanyl-6-(4-diethylamino-phenylamino)-pyrimidin-4-yl]-piperazin-l-yl}- pyridin-4-yl-methanone;

{4-[2-Butylsulfanyl-6-(4-diethylamino-phenylamino)-pyrimidin-4-yl]-piperazin-l-yl}- pyridin-4-yl-methanone;

{4-[2-Butylsulfanyl-6-(4-diethylamino-phenylamino)-pyrimidin-4-yl]-piperazin-l-yl}- pyrimidin-2-yl-methanone;

{4-[6-(4-Diethylammo-phenyl)-methyl-amino]-2-ethylsulfanyl-pyrimidin-4-yl}- piperazin- 1 -yl} -phenyl-methanone; {4-[6-(4-Dimethylamino-phenyl)-methyl-amino]-2-ethylsulfanyl-pyrimidin-4-yl}- piperazin- 1 -yl} -phenyl-methanone;

[4-(6-{[4-(Benzyl-methyl-amino)-phenyl]-methyl-amino}-2-ethylsulfanyl-pyrimidin-4- yl)-piperazin-l-yl]-phenyl-methanone;

(4-{6-[(4-Diethylamino-phenyl)-methyl-amino]-2-ethyl-pyrimidin-4-yl}-piperazin-l-yl)- phenyl-methanone;

6-(Ethyl-2-(4-morpholin-4-yl-phenylamino)-nicotinic acid ethyl ester;

6-(Ethyl-2-(4-morpholin-4-yl-phenylamino)-nicotinic acid butyl ester;

6-(Ethyl-2-(4-moφholin-4-yl-phenylamino)-nicotinic acid benzyl ester;

6-(n-Butyl-2-(4-morpholin-4-yl-phenylamino)-nicotinic acid butyl ester; 6-Butyl-2-[methyl-(4-moφholin-4-yl-phenyl)amino]-nicotinic acid butyl ester;

6-Butyl-2-[(4-moφholin-4-yl-phenyl)-propyl-amino]-nicotinic acid butyl ester;

6-Butyl-2-(4-piperazin-l-yl-phenylamino)-nicotinic acid; and

6-Butyl-2- {methyl- [4-(4-methyl-piperazin-l -yl)-phenyl] -amino} -nicotinic acid.

34. The compound according to any one of claims 1 to 33, wherein the compound is in the form of a pharmaceutically acceptable salt.

35. The compound according to any one of claims 1 to 33, wherein the compound is present as a single isomer or a mixture of stereoisomers, or tautomers.

36. A pharmaceutical composition comprising, as an active ingredient, a compound according to any one of claims 1 to 35.

37. The pharmaceutical composition of claim 36, wherein the composition is a solid or a liquid adapted for oral administration.

38. A method of inhibiting HCV comprising contacting HVC with a compound of any one of claims 1 to 35.

39. A method of inhibiting HCV comprising contacting a compound of any one of claims 1 to 35 in a subject in order to inhibit HCV in vivo.

40. A compound exhibiting HCV protease inhibitory activity, wherein the compound is a compound according to any one of claims 1 to 35.

41. A method of treating liver disease in a patient comprising administering to the patient a therapeutically effective amount of a compound or pharmaceutical composition of any one of claims 1 to 37.

42. The use of a compound or a composition as defined in any one of claims 1 to 37, or a pharmaceutically acceptable salt, prodrug or solvate thereof, for preparing a medicament for use in the treatment of liver diseases.