NOVEL VIRAL REPLICATION INHIBITORS

FIELD OF THE INVENTION

The present invention relates to a series of novel compounds, processes for their preparation, their use to treat or prevent viral infections and their use to manufacture a medicine to treat or prevent viral infections, particularly infections with viruses belonging to the family of the Flaviviridae and more preferably infections with Hepatitis C virus (HCV).

BACKGROUND OF THE INVENTION

The family of the Flaviviridae consists of 3 genera, the pestiviruses, the flaviviruses and the hepaciviruses and also contains the hepatitis G virus (HGV/GBV-C) that has not yet been assigned to a genus. The World Health Organization estimates that world- wide 170 million people (3% of the world's population) are chronically infected with HCV. These chronic carriers are at risk of developing cirrhosis and/or liver cancer. In studies with a 10 to 20 year follow-up, cirrhosis developed in 20 — 30 % of the patients, 1 to 5% of whom may develop liver cancer during the next then years. The only treatment option available today is the use of interferon α-2 (or its pegylated from) either alone or combined with ribavirin. However, sustained response is only observed in about 40% of the patients and treatment is associated with serious adverse effects. There is thus an urgent need for potent and selective inhibitors of the replication of the HCV in order to treat infections with HCV. Furthermore, the study of specific inhibitors of HCV replication has been hampered by the fact that it is not possible to propagate HCV (efficiently) in cell culture.

Currently, the standard therapy for HCV infections is to use a combinatino of Ribavirin and Interferon, but this treatment strategy is not satisfactory for most of the patients. Therefore, there is a clear need in the field for alternative antiviral compounds, furthermore with a good activity vs toxicity profile and this specifically for the virusses of the family of the Flaviviridae, more specifically for Hepatitis C Virus

The present invention provides for novel compounds which show activity against virusses, more specifically against HCV. The prior art does not lead a person skilled in the art to the compounds of the present invention and to their use as antiviral compounds.

SUMMARY OF THE INVENTION

Herein we disclose our new findings that novel triazol nucleoside analogs exhibited potent inhibition effects on HCV. Cytotoxicity was found low for these compounds.

In the present invention, new selective anti-viral compounds are being provided. The compounds are novel triazol nucleoside analogs and it has been shown that they possess an anti-viral activity. Members of the Flaviviridae family are being inhibited. The present invention demonstrates that the compounds inhibit the replication of HCV. Therefore, these novel triazol nucleoside analogs constitute a new potent class of anti-viral compounds that can be used in the treatment and prevention of viral infections in animals, mammals and humans, more specifically for the treatment and prevention of HCV.

The present invention relates to novel compounds. The invention further relates to novel compounds having anti-viral activity. Most particularly, the invention relates to novel compounds, in a particular embodiment being triazol nucleoside analogs, which inhibit the replication of viruses of the family of the Flaviviridae and yet more specifically to compounds that inhibit the replication of HCV (Hepatitis C Virus) infections. The present invention furthermore relates to the compounds for use as a medicine and to the use of the compounds as a medicine and more specifically to use the compounds as an anti-viral. The invention also relates to methods for preparation of all such compounds and pharmaceutical compositions comprising them. The invention further relates to the use of said compounds in the manufacture of a medicament useful for the treatment of HCV infections, as well as for treatment of other viral infections, especially other infections with RNA-viruses. The present invention also relates to a method of treatment of viral infections, by using said compounds.

According to a first aspect, the invention relates to novel compounds, which according to the general embodiment of the invention correspond to compounds according to the general

formula I (I-A or I-B), pharmaceutically acceptable salts, solvates, tautomers, isomers, phosphonates thereof or prodrugs of any of the foregoing,

wherein:

- each R ¹ is independently selected from hydrogen; alkyl; alkenyl; cycloalkyl; cycloalkenyl; aryl; arylalkyl; heterocyclyl; and heterocyclyl-alkyl; wherein said alkyl, alkenyl, cycloalkyl, cycloalkenyl, aryl, arylalkyl, heterocyclyl and heterocyclyl-alkyl can be substituted with one or more R ³ ; - each R is independently selected from hydrogen; alkyl; alkenyl; aryl; and acyl;

- each R ³ is independently selected from halogen; hydroxy; amino; nitro; cyano; -CF ₃ ; acyl; alkyl; alkenyl; alkynyl; aryl; and arylalkyl; wherein each of said alkyl, alkenyl, alkynyl, aryl, and arylalkyl can be substituted with one or more halogen, hydroxy, amino, cyano or CF ₃ ; - each R ⁴ is independently selected from -NH ₂ ; -NHR ₅ ; -OH; -C(O)R ₅ ; and alkoxy (in particular C _1-6 alkoxy);

- each R ₅ is independently selected from alkyl; alkenyl; alkynyl; aryl; heterocyclyl; arylalkyl; aryl-alkenyl; aryl-alkynyl; heterocyclyl-alkyl; heterocyclyl-alkenyl; and heterocyclyl- alkynyl; - each R ⁶ and R ⁷ are selected from hydrogen; or are taken together to form -CHOR ² -

CHOR ² -.

According to a particular embodiment, the invention relates to novel compounds, according to the general formula II (II-A or II-B) and/or III (III-A or III-B), pharmaceutically acceptable salts, solvates, tautomers, isomers, phosphonates thereof or prodrugs of any of the foregoing,

ii-A H-B

III-A III-B wherein:

- each R ¹ is independently selected from hydrogen; alkyl; alkenyl; cycloalkyl; cycloalkenyl; aryl; arylalkyl; heterocyclyl and heterocyclyl-alkyl; wherein said alkyl, alkenyl, cycloalkyl, cycloalkenyl, aryl, arylalkyl, heterocyclyl and heterocyclyl-alkyl can be substituted with one or more R ³ ;

- each R is independently selected from hydrogen; alkyl; alkenyl; aryl; and acyl; and

- each R ³ is independently selected from halogen; hydroxy; amino; nitro; cyano; -CF ₃ ; acyl; alkyl; alkenyl; alkynyl; aryl; and arylalkyl; wherein each of said alkyl, alkenyl, alkynyl, aryl, and arylalkyl can be substituted with one or more halogen, hydroxy, amino, cyano or CF ₃ ;

- each R ⁴ is independently selected from -NH ₂ ; -NHR ⁵ ; -OH; -C(O)R ⁵ ; and alkoxy (in particular C _1-6 alkoxy); and

- each R ₅ is independently selected from alkyl; alkenyl; alkynyl; aryl; heterocyclyl; arylalkyl; aryl-alkenyl; aryl-alkynyl; heterocyclyl-alkyl; heterocyclyl-alkenyl; and heterocyclyl- alkynyl.

A particular embodiment of the invention relates to the compounds according to formulae described herein wherein R ² is hydrogen. In another particular embodiment, acyl is selected from alkanoyl, alkenoyl, alkynoyl, aroyl, and heterocyclyl-carbonyl. In yet another particular

embodiment, R ⁴ is selected from -NH ₂ and -OCH ₃ . In a particular embodiment of the invention, heterocyclyl is selected from heteroaryl.

In another particular embodiment, the present invention relates to compounds according to the general formulae IV (IV-A or IV-B) and/or V (V-A or V-B), pharmaceutically acceptable salts, solvates, tautomers, isomers, phosphonates thereof or prodrugs of any of the foregoing,

V-A V-B

wherein R ² , R ³ and R ⁴ are as for the formulae herein above and n is selected from 0, 1, 2 or 3. In a particular embodiment of the foraiuluae IV and V, the compounds of the invention comprise one R ³ substituent in the para-position (4-position) of the phenyl ring.

In yet another particular embodiment, the compounds of the invention are according to formula VI, pharmaceutically acceptable salts, solvates, tautomers, isomers, phosphonates thereof or prodrugs of any of the foregoing,

wherein R ³ is as in formula IV or V.

Yet a more particular embodiment relates to the compounds selected from

- l-(2-Hydroxy-ethoxymethyl)-5-phenylethynyl-lH-[l,2,4]triazol e-3-carboxylic acid amide; - 5-(4-Fluoro-phenyle1iiynyl)-l-(2-hydroxy-e1iioxymethyl)-lH-[ l,2,4]triazole-3-carboxylic acid amide;

5-(4-Methyl-phenylemynyl)-l-(2-hydroxy-ethoxymethyl)-lH-[ l,2,4]triazole-3-carboxylic acid amide; and

- l-(2-Hydroxy-emoxyme1iiyl)-5-(3-methyl-but-3-en-l-ynyl)-lH-[ l,2,4]triazole-3-carboxylic acid amide.

- Methyl 5-(2-Triflouromethyl-phenylethynyl)- 1 -(2,3 ,5-tri-O-acetyl-β-D-ribofuranosyl)- 1 H- [1,2,4] triazole-3-carboxylate;

- Methyl 5-(4-Fluoro-phenylethynyl)-l-(2,3,5-tri-O-acetyl-β-D-ribofu ranosyl)-lH-[l,2,4] triazole-3-carboxylate; - Methyl 5-(Thioρhen-3-yl ethynyl)-l-(2,3,5-tri-O-acetyl-β-D-ribofuranosyl)-lH-[l,2 ₅ 4] triazole-3-carboxylate;

- Methyl 5-(l-Cyclopentanol ethynyl)-l-(2,3,5-tri-O-acetyl-β-D-ribofuranosyl)-lH-[l,2 ₅ 4] triazole-3 -carboxylate;

- 5-(4-Memoxy-phenyle1iιynyl)-l-(2,3,5-tri-Hydroxy-β-D-ribof uranosyl)-lH-[l,2,4] triazole- 3-carboxylic acid amide;

5-(4-Triflouromethyl-ρhenylemynyl)-l-(2,3,5-tri-Hydroxy- β-D-ribofuranosyl)-lH-[l,2,4] triazole-3 -carboxylic acid amide;

5-(3-Triflouromethyl-phenylemynyl)-l-(2 ₅ 3,5-M-Hydroxy-β-D-ribofuranosyl)-lH-[l,2,4] triazole-3 -carboxylic acid amide; - 5-(4-Fluoro-ρhenylemynyl)-l-(2,3,5-tri-Hydroxy-β-D-ribofur anosyl)-lH-[l,2,4] triazole-3- carboxylic acid amide;

- 5-(2-Fluoro-ρhenyletiiynyl)-l-(2,3,5-tri-Hydroxy-β-D-ribof uranosyl)-lH-[l,2,4] triazole-3- carboxylic acid amide;

- 5-(Thiophen-2-yl ethynyl)-l-(2,3,5-tri-Hydroxy-β-D-ribofuranosyl)-lH-[l,2,4] triazole-3- carboxylic acid amide;

- 5-(Thiophen-3-yl ethynyl)-l-(2,3,5-tri-Hydroxy-β-D-ribofuranosyl)-lH-[l,2,4] triazole-3- carboxylic acid amide;

- Methyl 3-(3-Triflouromethyl-phenylethynyl)-l-(23,5-tri-O-acetyl-β- D-ribofuranosyl)-lH- [1,2,4] triazole-5-carboxylate;

- Methyl 3-(2-Fluoro-phenylethynyl)-l-(2,3,5-tri-O-acetyl-β-D-ribofu ranosyl)-lH-[l,2,4] triazole-5 -carboxylate; - Methyl 3-(Thiophen-3-yl ethynyl)-l-(2,3,5-tri-O-acetyl-β-D-ribofuranosyl)-lH-[l,2,4 ] triazole-5 -carboxylate;

- Methyl 3-(l-me%l-lH-imidazole-4-etiiynyl)-l-(2,3,5-1xi-O-ace1yl-β- D-riboforanosyl)-lH- [1,2,4] triazole-5-carboxylate;

- Methyl 3-(l-Cyclopentanol ethynyl)-l-(2,3,5-tri-O-acetyl-β-D-ribofuranosyl)-lH-[l,2,4 ] triazole-5-carboxylate;

3-(2-Triflourome1hyl-ρhenylethynyl)-l-(2,3,5-tri-O-acetyl-� �-D-ribofuranosyl)-lH-[l,2 ₅ 4] triazole-5- carboxylic acid amide;

- 3 -(4-Chloro-phenylethynyl)- 1 -(2,3 ,5-tri-Hydroxy-β-D-riboturanosyl)- IH-[1 ,2,4] triazole-5- carboxylic acid amide; - 3-(Tbiophen-3-yl ethynyl)-l-(2,3,5-tri-Hydroxy-β-D-ribofuranosyl)-lH-[l,2,4] triazole-5- carboxylic acid amide; and any other compound exemplified herein.

A second aspect of the present invention relates to the novel compounds of the invention, more in particular according to the formulas I, II, III, IV, V, VI and embodiments thereof for their use as a medicine, more in particular for their use as an antivral medicine and for their use in the prevention or treatment of a viral infection..

Another aspect of the present invention relates to the use of the novel compounds of the invention, more in particular according to the formulas I, II, III, IV, V, VI and embodiments thereof for the manufacture of a medicament for the treatment or prevention of a viral infection in a mammal.

The invention also relates to the use of the novel compounds of the invention, more in particular according to the formulas I, II, III, IV, V, VI and embodiments thereof as a pharmaceutically active ingredient, especially as an inhibitor of the viral replication, more preferably as an inhibitor of the replication of a virus of the family of the Flaviviridae and yet more preferably as an inhibitor of the replication of HCV.

The present invention relates to a pharmaceutical composition comprising the novel compounds of the invention, more in particular according to the formulas I, II, III, IV, V, VI and embodiments thereof as an active ingredient together with a pharmaceutically acceptable carrier.

The present invention further relates to a method of treatment of a viral infection in a mammal, including a human, comprising administering to the mammal in need of such treatment (a therapeutically effective amount of) a the novel compounds of the invention, more in particular according to the formulas I, II, III, IV, V, VI and embodiments thereof as an active ingredient, optionally in a mixture with at least a pharmaceutically acceptable carrier.

The present invention further relates to a composition for separate, combined or sequential use in the treatment or prophylaxis of anti- viral infections, comprising: a) one or more the novel compounds of the invention, more in particular according to the formulas I, II, III, IV, V, VI and embodiments thereof, and b) one or more compounds effective in the treatment or prophylaxis of viral infections, including Flaviviral enzyme inhibitors; in proportions such as to provide a synergistic effect in the said treatment of prophylaxis.

The invention further relates to methods for the preparation of the compounds according to formulas as detailed above, more particularly to methods for the preparation of the compounds specifically disclosed herein, to pharmaceutical compositions comprising them in admixture with at least a pharmaceutically acceptable carrier, the active ingredient optionally being in a concentration range of about 0.1-100% by weight, and to the use of these derivatives namely as antiviral drugs, more particularly as drugs useful for the treatment of subjects suffering from HCV infection.

In a particular embodiment of the aspects of the invention, said viral infection is an infection with an RNA- virus, yet more in particular with a virus of the family of the Flaviviridae. Yet more in particular, said viral infection is an infection with Hepatitis C virus (HCV). In another particular embodiment, said mammal in need of treatment or prevention of a viral infection is a human.

The invention also relates to a method for preparing the compounds according to the formulas above and embodiments thereof as described herein. Such a method may essentially comprise the steps of reacting 5-halogeno-l-[(2-hydroxyethoxy)methyl]-l,2,4-triazole-3-carb oxylate, 3- halogeno- 1 -[(2-hydroxyethoxy)methyl] - 1 ,2,4-triazole-5-carboxylate, 5 -halogeno- 1 -(2,3 ,5 -tri- O-acetyl-β-D-ribofuranosyl)-l,2,4-triazole-3-carboxylate or 3-halogeno-l-(2,3,5-tri-O-acetyl- β-D-ribofuranosyl)-l,2,4-triazole-5-carboxylate with terminal alkynes under Pd-catalyzed Sonogashira coupling reactions. In a particular embodiment, the method essentially comprises the step of reacting 5-halogeno-l-[(2-hydroxyethoxy)methyl]-l,2,4-triazole-3-carb oxamide, 3-halogeno-l-[(2-hydroxyethoxy)methyl]-l,2,4-triazole-5-carb oxamide, 5-halogeno-l -(2,3,5- tri-O-acetyl-β-D-ribofuranosyl)-l,2,4-triazole-3-carboxamid e or 3-halogeno-l-(2,3,5-tri-O- acetyl-β-D-ribofuranosyl)-l,2,4-triazole-5-carboxamide with terminal alkynes under Pd- catalyzed Sonogashira coupling reactions.

In a particular embodiment, the invention relates to novel compounds, which according to the general embodiment of the invention correspond to compounds according to the general formula Z-I, pharmaceutically acceptable salts, solvates, tautomers, isomers, phosphonates thereof or prodrugs of any of the foregoing,

wherein:

- R ¹ is selected from alkyl; alkenyl; cycloalkyl; cycloalkenyl; aryl; arylalkyl; heterocycle and heterocycle-alkyl; wherein said alkyl, alkenyl, cycloalkyl, cycloalkenyl, aryl, arylalkyl, heterocycle and heterocycle-alkyl can be substituted with one or more R ³ ;

- R ² is selected from hydrogen; alkyl; alkenyl; aryl; and acyl; and - R ³ is selected from halogen; hydroxy; amino; nitro; cyano; acyl; alkyl; alkenyl; alkynyl; aryl; and arylalkyl.

A particular embodiment of the invention relates to the compounds according to formula Z-I wherein R ² is hydrogen. In another particular embodiment, acyl is selected from alkanoyl,

alkenoyl, alkynoyl, aroyl, and heterocycle-carbonyl. In another particular embodiment, the present invention relates to compounds according to the general formula Z-2, pharmaceutically acceptable salts, solvates, tautomers, isomers, phosphonates thereof or prodrugs of any of the foregoing,

wherein R ³ is selected from halogen; hydroxy; amino; nitro; cyano; acyl; alkyl; alkenyl; alkynyl; and aryl and n is selected from 0, 1, 2 or 3.

In yet another particular embodiment, the compounds of the invention are according to formula Z-3, pharmaceutically acceptable salts, solvates, tautomers, isomers, phosphonates thereof or prodrugs of any of the foregoing,

wherein R and n are as in formula Z-2.

DETAILED DESCRIPTION OF THE INVENTION

In each of the following definitions, the number of carbon atoms represents the maximum number of carbon atoms generally optimally present in the substituent or linker; it is understood that where otherwise indicated in the present application, the number of carbon atoms represents the optimal maximum number of carbon atoms for that particular substituent or linker.

The terms mentioned herein with prefixes as C _1-18 or C ₁ - _I0 can also be used with lower numbers of carbon atoms such as C _1-8 or Ci _-6 . If for example the term C ₁ -C ₆ is used, it refers to the presence of between 1 and 6 carbon atoms.

In each of the following definitions, the number of carbon atoms represents the maximum number of carbon atoms generally optimally present in the substituent or linker; it is understood that where otherwise indicated in the present application, the number of carbon atoms represents the optimal maximum number of carbon atoms for that particular substituent or linker.

The term "alkyl" as used herein refers to C _1-18 normal, secondary, or tertiary hydrocarbon chains. Examples are methyl, ethyl, 1 -propyl, 2-propyl, 1 -butyl, 2-methyl-l- propyl(i-Bu), 2-butyl (s-Bu) 2-methyl-2-propyl (t-Bu), 1-pentyl (n-pentyl), 2-pentyl, 3-pentyl, 2-methyl-2-butyl, 3-methyl-2-butyl, 3 -methyl- 1 -butyl, 2-methyl-l -butyl, 1-hexyl, 2-hexyl, 3- hexyl, 2-methyl-2-pentyl, 3-methyl-2-pentyl, 4-methyl-2-pentyl, 3-methyl-3-pentyl, 2-methyl- 3-ρentyl, 2,3-dimethyl-2-butyl, 3,3-dimethyl-2-butyl, rø-pentyl, π-hexyl, n-heptyl, rø-octyl, n- nonyl, rø-decyl, «-undecyl, w-dodecyl, rø-tridecyl, π-tetradecyl, «-pentadecyl, n-hexadecyl, n- heptadecyl, rø-octadecyl, «-nonadecyl and rø-icosyl. As used herein and unless otherwise stated, the term "cycloalkyl" means a monocyclic saturated hydrocarbon monovalent radical having from 3 to 10 carbon atoms, such as for instance cyclopropyl, cyclobutyl, cyclopentyl, cyclohexyl, cycloheptyl, cyclooctyl and the like, or a C _7-10 polycyclic saturated hydrocarbon monovalent radical having from 7 to 10 carbon atoms such as, for instance, norbornyl, fenchyl, trimethyltricycloheptyl or adamantyl.

The terms "alkenyl" and "cycloalkenyl" as used herein is C _2- Is normal, secondary or tertiary and respectively C ₃ _io cyclic hydrocarbon with at least one site (usually 1 to 3, preferably 1) of unsaturation, i.e. a carbon-carbon, sp2 double bond. Examples include, but are not limited to: ethylene or vinyl (-CH=CH2), allyl (-CH2CH=CH2), cyclopentenyl (- C5H7), and 5-hexenyl (-CH2 CH2CH2CH2CH=CH2). The double bond may be in the cis or trans configuration. The terms "alkynyl" and "cycloalkynyl" as used herein refer respectively C _2-1S normal, secondary, tertiary or the C _3-10 cyclic hydrocarbon with at least one site (usually 1 to 3, preferably 1) of unsaturation, i.e. a carbon-carbon, sp triple bond. Examples include, but are not limited to: acetylenic (-G≡CH) and propargyl (-CH2C≡CH).

The term "acyl" as used herein refers to substituted C(O), such as -C(O)(alkyl, alkenyl, alkynyl, aryl, heterocycle, arylalkyl, arylalkenyl, arylalkynyl, heterocycle-alkyl, heterocycle-alkenyl or heterocycle-alkynyl) such as for example an alkanoyl group (alkylcarbonyl, alkyl coupled to a carbonyl), an aroyl group (arylcarbonyl, aryl attached to a carbonyl), a arylalkanoyl or a alkylaroyl group, wherein the C(O) is coupled to another

Il

molecule or atom and wherein said alkyl, alkenyl and alkynyl can contain a heteroatom in or at the end of the hydrocarbon chain, said heteroatom selected from O, S and N.

The term "aryl" as used herein means a aromatic hydrocarbon radical of 5-20 carbon atoms derived by the removal of hydrogen from a carbon atom of a parent aromatic ring system. Typical aryl groups include, but are not limited to 1 ring, or 2 or 3 rings fused together, radicals derived from benzene, naphthalene, spiro, anthracene, biphenyl, and the like.

"Arylalkyl" as used herein refers to an alkyl radical in which one of the hydrogen atoms bonded to a carbon atom, typically a terminal or sp3 carbon atom, is replaced with an aryl radical. Typical arylalkyl groups include, but are not limited to, benzyl, 2-phenylethan-l- yl, 2-phenylethen-l-yl, naphthylmethyl, 2-naphthylethan-l-yl, 2-naphthylethen-l-yl, naphthobenzyl, 2-naphthophenylethan-l-yl and the like. The arylalkyl group comprises 6 to 20 carbon atoms, e.g. the alkyl moiety, including alkanyl, alkenyl or alkynyl groups, of the arylalkyl group is 1 to 6 carbon atoms and the aryl moiety is 5 to 14 carbon atoms. The same reasoning would apply for the terms "aryl-alkenyl" and "aryl-alkynyl" except that in these situations it is an alkenyl radical, respectively an alkynyl radical in which one of the hydrogen atoms bonded to a carbon atom, is replaced with an aryl radical.

The term "heterocyclyl" as used herein means a saturated, unsaturated or aromatic ring system including at least one N, O ₅ or S. Heterocyclyl thus include heteroaryl groups. Heterocyclyl as used herein includes by way of example and not limitation these heterocycles described in Paquette, Leo A. "Principles of Modern Heterocyclic Chemistry" (W.A. Benjamin, New York, 1968), particularly Chapters 1, 3, 4, 6, 7, and 9; "The Chemistry of Heterocyclic Compounds, A series of Monographs" (John Wiley & Sons, New York, 1950 to present), in particular Volumes 13, 14, 16, 19, and 28; Katritzky, Alan R., Rees, CW. and Scriven, E. "Comprehensive Heterocyclic Chemistry" (Pergamon Press, 1996); and J. Am. Chem. Soc. (1960) 82:5566. In a particular embodiment, heterocyclyl means pyridyl, dihydroypyridyl, tetrahydropyridyl (piperidyl), thiazolyl, tetrahydrothiophenyl, sulfur oxidized tetrahydrothiophenyl, furanyl, thienyl, pyrrolyl, pyrazolyl, imidazolyl, tetrazolyl, benzofuranyl, thianaphthalenyl, indolyl, indolenyl, quinolinyl, isoquinolinyl, benzimidazolyl, piperidinyl, 4-piperidonyl, pyrrolidinyl, 2-pyrrolidonyl, pyrrolinyl, tetrahydrofuranyl, bis-tetrahydrofuranyl, tetrahydropyranyl, bis- tetrahydropyranyl, tetrahydroquinolinyl, tetrahydroisoquinolinyl, decahydroquinolinyl,

octahydroisoquinolinyl, azocinyl, triazinyl, 6H-l,2,5-thiadiazinyl, 2H,6H-l,5,2-dithiazinyl, thianthrenyl, pyranyl, isobenzoiuranyl, chromenyl, xanthenyl, phenoxathinyl, 2H-pyrrolyl, isothiazolyl, isoxazolyl, pyrazinyl, pyridazinyl, indolizinyl, isoindolyl, 3H-indolyl, IH- indazoly, purinyl, 4H-quinolizinyl, phthalazinyl, naphthyridinyl, quinoxalinyl, quinazolinyl, cinnolinyl, pteridinyl, 4aH-carbazolyl, carbazolyl, β-carbolinyl, phenanthridinyl, acridinyl, pyrimidinyl, phenanthrolinyl, phenazinyl, phenothiazinyl, furazanyl, phenoxazinyl, isochromanyl, chromanyl, imidazolidinyl, imidazolinyl, pyrazolidinyl, pyrazolinyl, piperazinyl, indolinyl, isoindolinyl, quinuclidinyl, morpholinyl, oxazolidinyl, benzotriazolyl, benzisoxazolyl, oxindolyl, benzoxazolinyl, benzothienyl, benzothiazolyl and isatinoyl. ηeterocyclyl-alkyl" as used herein refers to an alkyl radical in which one of the hydrogen atoms bonded to a carbon atom, typically a terminal or sp3 carbon atom, is replaced with a heterocyclyl radical. The same reasoning would apply for the terms "heterocyclyl- alkenyl" and "heterocyclyl-alkynyl" except that hi these situations it is an alkenyl radical, respectively an alkynyl radical in which one of the hydrogen atoms bonded to a carbon atom, is replaced with an heterocyclyl radical.

"Heteroaryl" means pyridyl, dihydropyridyl, pyridazinyl, pyrimidinyl, pyrazinyl, s- triazinyl, oxazolyl, imidazolyl, thiazolyl, isoxazolyl, pyrazolyl, isothiazolyl, furanyl, thiofuranyl, thienyl, and pyrrolyl.

By way of example, carbon bonded heterocyclic rings (heterocyclyl) are bonded at position 2, 3, 4, 5, or 6 of a pyridine, position 3, 4, 5, or 6 of a pyridazine, position 2, 4, 5, or 6 of a pyrimidine, position 2, 3, 5, or 6 of a pyrazine, position 2, 3, 4, or 5 of a furan, tetrahydrofuran, thiofuran, thiophene, pyrrole or tetrahydropyrrole, position 2, 4, or 5 of an oxazole, imidazole or thiazole, position 3, 4, or 5 of an isoxazole, pyrazole, or isothiazole, position 2 or 3 of an aziridine, position 2, 3, or 4 of an azetidine, position 2, 3, 4, 5, 6, 7, or 8 of a quinoline or position 1, 3, 4, 5, 6, 7, or 8 of an isoquinoline. Still more typically, carbon bonded heterocycles include 2-pyridyl, 3-pyridyl, 4-pyridyl, 5-pyridyl, 6-pyridyl, 3- pyridazinyl, 4-pyridazinyl, 5-pyridazinyl, 6-pyridazinyl, 2-pyrimidinyl, 4-pyrimidinyl, 5- pyrimidinyl, 6-pyrimidinyl, 2-pyrazinyl, 3-pyrazinyl, 5-pyrazinyl, 6-pyrazinyl, 2-thiazolyl, 4- thiazolyl, or 5-thiazolyl. By way of example, nitrogen bonded heterocyclic rings (heterocyclyl) are bonded at position 1 of an aziridine, azetidine, pyrrole, pyrrolidine, 2-pyrroline, 3-pyrroline, imidazole, imidazolidine, 2-imidazoline, 3 -imidazoline, pyrazole, pyrazoline, 2-pyrazoline, 3-pyrazoline, piperidine, piperazine, indole, indoline, lH-indazole, position 2 of a isoindole, or isoindoline,

position 4 of a morpholine, and position 9 of a carbazole, or β-carboline. Still more typically, nitrogen bonded heterocycles include 1-aziridyl, 1-azetedyl, 1-pyrrolyl, 1-imidazolyl, 1- pyrazolyl, and 1-piperidinyl.

As used herein and unless otherwise stated, the term "alkoxy" refers to substituents wherein an alkyl radical as defined herein, is attached to an oxygen atom through a single bond, such as but not limited in methoxy, ethoxy, propoxy, butoxy, and the like.

As used herein and unless otherwise stated, the term "halogen" means any atom selected from the group consisting of fluorine (F), chlorine (Cl), bromine (Br) and iodine (I).

Any substituent designation that is found in more than one site in a compound of this invention shall be independently selected.

Substituents optionally are designated with or without bonds. Regardless of bond indications, if a substituent is polyvalent (based on its position in the structure referred to), then any and all possible orientations of the substituent are intended.

The compounds of the invention optionally are bound covalently to an insoluble matrix and used for affinity chromatography (separations, depending on the nature of the groups of the compounds, for example compounds with pendant aryl are useful in hydrophobic affinity separations.

It has been shown in the present invention that novel compounds show potent antiviral activity, especially against HCV.

The compounds of the invention can be employed for the treatment or prophylaxis of viral infections, more particularly Flaviviral infections, in particular of HCV. When using one or more derivatives of the formulae I, II, III, IV, V, Vl and embodiments thereof as defined herein: the active ingredients of the compound(s) may be administered to the mammal (including a human) to be treated by any means well known in the art, i.e. orally, intranasally,. subcutaneously, intramuscularly, intradermally, intravenously, intra-arterially, parenterally or by catheterization.

- the therapeutically effective amount of the preparation of the compound(s), especially for the treatment of viral infections in humans and other mammals, preferably is a flaviviral enzyme inhibiting amount. More preferably, it is a flaviviral replication inhibiting amount

or a flaviviral enzyme inhibiting amount of the derivative(s) of formula I, π, III, IV, V, Vl as defined herein corresponds to an amount which ensures a plasma level of between lμg/ml and 100 mg/ml, optionally of 10 mg/ml. Depending upon the pathologic condition to be treated and the patient's condition, the said effective amount may be divided into several sub-units per day or may be administered at more than one day intervals.

The present invention further relates to a method for preventing or treating a viral infections in a subject or patient by administering to the patient in need thereof a therapeutically effective amount of compounds of the present invention. The therapeutically effective amount of the preparation of the compound(s), especially for the treatment of viral infections in humans and other mammals, preferably is a flaviviral enzyme inhibiting amount. More preferably, it is a flaviviral replication inhibiting amount or a flaviviral enzyme inhibiting amount of the derivative(s) of formula I, II, III, IV, V, VI and embodiments thereof as defined herein. Depending upon the pathologic condition to be treated and the patient's condition, the said effective amount may be divided into several sub-units per day or may be administered at more than one day intervals.

The present invention also relates to a combination of different antiviral drugs of the invention or to a combination of the antiviral drugs of the invention with other drugs that exhibit anti-HCV activity.

The invention also relates to a pharmaceutical composition or combined preparation of antiviral drugs and containing: Either: A)

(a) a combination of two or more of the compounds of the present invention, and

(b) optionally one or more pharmaceutical excipients or pharmaceutically acceptable carriers, for simultaneous, separate or sequential use in the treatment or prevention of a viral infection or B)

(c) one or more anti- viral agents, and

(d) at least one of the compounds of the present invention, and

(e) optionally one or more pharmaceutical excipients or pharmaceutically acceptable carriers,

for simultaneous, separate or sequential use in the treatment or prevention of a viral infection.

Suitable anti-viral agents for inclusion into the antiviral compositions or combined preparations of this invention include, for instance, interferon-alfa (either pegylated or not), 5 ribavirin and other selective inhibitors of the replication of HCV, such as a compound faling within the scope of disclosure EPl 162196, WO 03/010141, WO 03/007945 and WO 03/010140, a compound falling within the scope of disclosure WO 00/204425, and other patents or patent applications within their patent families or all the foregoing filings and/or an inhibitor of flaviviral protease and/or one or more additional flavivirus polymerase inhibitors. 10

The pharmaceutical composition or combined preparation with activity against viral infection according to this invention may contain the compounds of the present invention over a broad content range depending on the contemplated use and the expected effect of the preparation. Generally, the content of the compounds of the present invention of the 15 combined preparation is within the range of 0.1 to 99.9% by weight, preferably from 1 to 99% by weight, more preferably from 5 to 95% by weight.

When using a pharmaceutical composition of combined preparation: the active ingredients may be administered to the mammal (including a human) to be 20. treated by any means well known in the art, i.e. orally, intranasally, subcutaneously, intramuscularly, intradermally, intravenously, intra-arterially, parenterally or by catheterization. - the therapeutically effective amount of each of the active agents, especially for the treatment of viral infections in humans and other mammals, particularly is a flaviviral 25 enzyme inhibiting amount.

When applying a combined preparation, the active ingredients may be administered simultaneously but it is also beneficial to administer them separately or sequentially, for instance within a relatively short period of time (e.g. within about 24 hours) in order to achieve their functional fusion in the body to be treated. 30

The invention also relates to the compounds of formula I, II, III, IV, V, VI and embodiments thereof being Used for inhibition of the proliferation of other viruses than HCV, particularly for the inhibition of other members of the family of the Flaviviridae, including but not limited to the Yellow fever virus, the Dengue fever virus, West Nile virus, Japanese encephalitis

virus, hepatitis G virus, bovine viral diarrhea virus, classical swine fever virus, border disease virus but also for the inhibition of other viruses including HIV and other retroviruses.

The present invention further provides veterinary compositions comprising at least one active ingredient as above defined together with a veterinary carrier therefor, for example in the treatment of BVDV. Veterinary carriers are materials useful for the purpose of administering the composition and may be solid, liquid or gaseous materials which are otherwise inert or acceptable in the veterinary art and are compatible with the active ingredient. These veterinary compositions may be administered orally, parenterally or by any other desired route.

More generally, the invention relates to the compounds of formula I, II, III, IV, V, VI and embodiments thereof being useful as agents having biological activity (particularly antiviral activity) or as diagnostic agents. Any of the uses mentioned with respect to the present invention may be restricted to a non-medical use, a non-therapeutic use, a non-diagnostic use, or exclusively an in vitro use, or a use related to cells remote from an animal. Those of skill in the art will also recognize that the compounds of the invention may exist in many different protonation states, depending on, among other things, the pH of their environment. While the structural formulae provided herein depict the compounds in only one of several possible protonation states, it will be understood that these structures are illustrative only, and that the invention is not limited to any particular protonation state - any and all protonated forms of the compounds are intended to fall within the scope of the invention.

The term "pharmaceutically acceptable salts" as used herein means the therapeutically active non-toxic salt forms which the compounds of formulas herein are able to form. Therefore, the compounds of this invention optionally comprise salts of the compounds herein, especially pharmaceutically acceptable non-toxic salts containing, for example, Na ⁺ , Li ⁺ , K ⁺ , Ca ²⁺ and Mg ²⁺ . Such salts may include those derived by combination of appropriate cations such as alkali and alkaline earth metal ions or ammonium and quaternary amino ions with an acid anion moiety, typically a carboxylic acid. The compounds of the invention may bear multiple positive or negative charges. The net charge of the compounds of the invention may be either positive or negative. Any associated counter ions are typically dictated by the synthesis and/or isolation methods by which the compounds are obtained. Typical counter ions include, but are

not limited to ammonium, sodium, potassium, lithium, halides, acetate, trifluoroacetate, etc., and mixtures thereof. It will be understood that the identity of any associated counter ion is not a critical feature of the invention, and that the invention encompasses the compounds in association with any type of counter ion. Moreover, as the compounds can exist in a variety of different forms, the invention is intended to encompass not only forms of the compounds that are in association with counter ions (e.g., dry salts), but also forms that are not in association with counter ions (e.g., aqueous or organic solutions). Metal salts typically are prepared by reacting the metal hydroxide with a compound of this invention. Examples of metal salts which are prepared in this way are salts containing Li ⁺ , Na ⁺ , and K ⁺ . A less soluble metal salt can be precipitated from the solution of a more soluble salt by addition of the suitable metal compound. In addition, salts may be formed from acid addition of certain organic and inorganic acids to basic centers, typically amines, or to acidic groups. Examples of such appropriate acids include, for instance, inorganic acids such as hydrohalic acids, e.g. hydrochloric or hydrobromic acid, sulfuric acid, nitric acid, phosphoric acid and the like; or organic acids such as, for example, acetic, propanoic, hydroxyacetic, 2-hydroxypropanoic, 2- oxopropanoic, lactic, pyruvic, oxalic (i.e. ethanedioic), malonic, succinic (i.e. butanedioic acid), maleic, fumaric, malic, tartaric, citric, methanesulfonic, ethanesulfonic, benzenesulfonic, p-toluenesulfonic, cyclohexanesulfamic, salicylic (i.e. 2-hydroxybenzoic), p- aminosalicylic and the like. Furthermore, this term also includes the solvates which the compounds of formula (I) as well as their salts are able to form, such as for example hydrates, alcoholates and the like. Finally, it is to be understood that the compositions herein comprise compounds of the invention in their unionized, as well as 2witterionic form, and combinations with stoichiometric amounts of water as in hydrates. Also included within the scope of this invention are the salts of the parental compounds with one or more amino acids, especially the naturally-occurring amino acids found as protein components. The amino acid typically is one bearing a side chain with a basic or acidic group, e.g., lysine, arginine or glutamic acid, or a neutral group such as glycine, serine, threonine, alanine, isoleucine, or leucine. The compounds of the invention also include physiologically acceptable salts thereof. Examples of physiologically acceptable salts of the compounds of the invention include salts derived from an appropriate base, such as an alkali metal (for example, sodium), an alkaline earth (for example, magnesium), ammonium and NX ₄ ⁺ (wherein X is C ₁ -C ₄ alkyl). Physiologically acceptable salts of an hydrogen atom or an amino group include salts of

organic carboxylic acids such as acetic, benzoic, lactic, fumaric, tartaric, maleic, malonic, malic, isethionic, lactobionic and succinic acids; organic sulfonic acids, such as methanesulfonic, ethanesulfonic, benzenesulfonic and p-toluenesulfonic acids; and inorganic acids, such as hydrochloric, sulfuric, phosphoric and sulfamic acids. Physiologically acceptable salts of a compound containing a hydroxy group include the anion of said compound in combination with a suitable cation such as Na ⁺ and NX ₄ ⁺ (wherein X typically is independently selected from H or a C ₁ -C ₄ alkyl group). However, salts of acids or bases which are not physiologically acceptable may also find use, for example, in the preparation or purification of a physiologically acceptable compound. All salts, whether or not derived form a physiologically acceptable acid or base, are within the scope of the present invention.

As used herein and unless otherwise stated, the term "enantiomer" means each individual optically active form of a compound of the invention, having an optical purity or enantiomeric excess (as determined by methods standard in the art) of at least 80% (i.e. at least 90% of one enantiomer and at most 10% of the other enantiomer), preferably at least 90% and more preferably at least 98%.

The term "isomers" as used herein means all possible isomeric forms, including tautomeric and sterochemical forms, which the compounds of formula I, II, III, IV, V, VI and embodiments thereof may possess, but not including position isomers. Typically, the structures shown herein exemplify only one tautomeric or resonance form of the compounds, but the corresponding alternative configurations are contemplated as well. Unless otherwise stated, the chemical designation of compounds denotes the mixture of all possible stereochemically isomeric forms, said mixtures containing all diastereomers and enantiorners (since the compounds of formula I, II, III, IV, V, VI and embodiments thereof may have at least one chiral center) of the basic molecular structure, as wel as the stereochemically pure or enriched compounds. More particularly, stereogenic centers may have either the R- or S- configuration, and multiple bonds may have either cis- or trans-configuration. Pure isomeric forms of the said compounds are defined as isomers substantially free of other enantiomeric or diastereomeric forms of the same basic molecular structure. In particular, the term "stereoisomerically pure" or "chirally pure" relates to compounds having a stereoisomers excess of at least about 80% (i.e. at least 90% of one isomer and at most 10% of the other possible isomers), preferably at least 90%, more preferably at least 94% and most preferably at least 97%. The terms "enantionierically pure" and "diastereomerically pure"

should be understood in a similar way, having regard to the enantiomeric excess, respectively the diastereomeric excess, of the mixture in question.

Separation of stereoisomers is accomplished by standard methods known to those in the art. One enantiomer of a compound of the invention can be separated substantially free of its opposing enantiomer by a method such as formation of diastereomers using optically active resolving agents ("Stereochemistry of Carbon Compounds," (1962) by E. L. Eliel, McGraw Hill; Lochmuller, C. H., (1975) J. Chromatogr., 113:(3) 283-302). Separation of isomers in a mixture can be accomplished by any suitable method, including: (1) formation of ionic, diastereomeric salts with chiral compounds and separation by fractional crystallization or other methods, (2) formation of diastereomeric compounds with chiral derivatizing reagents, separation of the diastereomers, and conversion to the pure enantiomers, or (3) enantiomers can be separated directly under chiral conditions. Under method (1), diastereomeric salts can be formed by reaction of enantiomerically pure chiral bases such as brucine, quinine, ephedrine, strychnine, a-methyl-b-phenylethylamine (amphetamine), and the like with asymmetric compounds bearing acidic functionality, such as carboxylic acid and sulfonic acid. The diastereomeric salts may be induced to separate by fractional crystallization or ionic chromatography. For separation of the optical isomers of amino compounds, addition of chiral carboxylic or sulfonic acids, such as camphorsulfonic acid, tartaric acid, mandelic acid, or lactic acid can result in formation of the diastereomeric salts. Alternatively, by method (2), the substrate to be resolved may be reacted with one enantiomer of a chiral compound to form a diastereomeric pair (Eliel, E. and Wilen, S. (1994) Stereochemistry of Organic Compounds, John Wiley & Sons, Inc., p. 322). Diastereomeric compounds can be formed by reacting asymmetric compounds with enantiomerically pure chiral derivatizing reagents, such as menthyl derivatives, followed by separation of the diastereomers and hydrolysis to yield the free, enantiomerically enriched xanthene. A method of determining optical purity involves making chiral esters, such as a menthyl ester or Mosher ester, a-methoxy-a- (trifluoromethyl)phenyl acetate (Jacob III. (1982) J. Org. Chem. 47:4165), of the racemic mixture, and analyzing the NMR spectrum for the presence of the two atropisomeric diastereomers. Stable diastereomers can be separated and isolated by normal- and reverse- phase chromatography following methods for separation of atropisomeric naphthyl- isoquinolines (Hoye, T., WO96/15111). Under method (3), a racemic mixture of two asymmetric enantiomers is separated by chromatography using a chiral stationary phase. Suitable chiral stationary phases are, for example, polysaccharides, in particular cellulose or

amylose derivatives. Commercially available polysaccharide based chiral stationary phases are ChiralCel™ CA, OA, OB5, OC5, OD, OF, OG, OJ and OK, and ChiralpakTM AD, AS, OP(H-) and OT(+). Appropriate eluents or mobile phases for use in combination with said polysaccharide chiral stationary phases are hexane and the like, modified with an alcohol such as ethanol, isopropanol and the like. ("Chiral Liquid Chromatography" (1989) W. J. Lough, Ed. Chapman and Hall, New York; Okamoto, (1990) "Optical resolution of dihydropyridine enantiomers by High-performance liquid chromatography using phenylcarbamates of polysaccharides as a chiral stationary phase", J. of Chromatogr. 513:375-378). The terms cis and trans are used herein in accordance with Chemical Abstracts nomenclature and include reference to the position of the substituents on a ring moiety. The absolute stereochemical configuration of the compounds of formula (1) may easily be determined by those skilled in the art while using well-known methods such as, for example, X-ray diffraction.

The compounds of the invention may be formulated with conventional carriers and excipients, which will be selected in accord with ordinary practice. Tablets will contain excipients, glidants, fillers, binders and the like. Aqueous formulations are prepared in sterile form, and when intended for delivery by other than oral administration generally will be isotonic. Formulations optionally contain excipients such as those set forth in the "Handbook of Pharmaceutical Excipients" (1986) and include ascorbic acid and other antioxidants, chelating agents such as EDTA, carbohydrates such as dextrin, hydroxyalkylcellulose, hydroxyalkylmethylcellulose, stearic acid and the like.

Subsequently, the term "pharmaceutically acceptable carrier" as used herein means any material or substance with which the active ingredient is formulated in order to facilitate its application or dissemination to the locus to be treated, for instance by dissolving, dispersing or diffusing the said composition, and/or to facilitate its storage, transport or handling without impairing its effectiveness. The pharmaceutically acceptable carrier may be a solid or a liquid or a gas which has been compressed to form a liquid, i.e. the compositions of this invention can suitably be used as concentrates, emulsions, solutions, granulates, dusts, sprays, aerosols, suspensions, ointments, creams, tablets, pellets or powders.

Suitable pharmaceutical carriers for use in the said pharmaceutical compositions and their formulation are well known to those skilled in the art, and there is no particular restriction to their selection within the present invention. They may also include additives such as wetting

agents, dispersing agents, stickers, adhesives, emulsifying agents, solvents, coatings, antibacterial and antifungal agents (for example phenol, sorbic acid, chlorobutanol), isotonic agents (such as sugars or sodium chloride) and the like, provided the same are consistent with pharmaceutical practice, i.e. carriers and additives which do not create permanent damage to mammals. The pharmaceutical compositions of the present invention may be prepared in any known manner, for instance by homogeneously mixing, coating and/or grinding the active ingredients, in a one-step or multi-steps procedure, with the selected carrier material and, where appropriate, the other additives such as surface-active agents. They may also be prepared by micronisation, for instance in view to obtain them in the form of microspheres usually having a diameter of about 1 to 10 μm, namely for the manufacture of microcapsules for controlled or sustained release of the active ingredients.

Suitable surface-active agents, also known as emulgent or emulsifier, to be used in the pharmaceutical compositions of the present invention are non-ionic, cationic and/or anionic materials having good emulsifying, dispersing and/or wetting properties. Suitable anionic surfactants include both water-soluble soaps and water-soluble synthetic surface-active agents. Suitable soaps are alkaline or alkaline-earth metal salts, unsubstituted or substituted ammonium salts of higher fatty acids (C _1O -C ₂₂ ), e.g. the sodium or potassium salts of oleic or stearic acid, or of natural fatty acid mixtures obtainable form coconut oil or tallow oil. Synthetic surfactants include sodium or calcium salts of polyacrylic acids; fatty sulphonates and sulphates; sulphonated benzimidazole derivatives and alkylarylsulphonates. Fatty sulphonates or sulphates are usually in the form of alkaline or alkaline-earth metal salts, unsubstituted ammonium salts or ammonium salts substituted with an alkyl or acyl radical having from 8 to 22 carbon atoms, e.g. the sodium or calcium salt of lignosulphonic acid or dodecylsulphonic acid or a mixture of fatty alcohol sulphates obtained from natural fatty acids, alkaline or alkaline-earth metal salts of sulphuric or sulphonic acid esters (such as sodium lauryl sulphate) and sulphonic acids of fatty alcohol/ethylene oxide adducts. Suitable sulphonated benzimidazole derivatives preferably contain 8 to 22 carbon atoms. Examples of alkylarylsulphonates are the sodium, calcium or alcanolamine salts of dodecylbenzene sulphonic acid or dibutyl-naphtalenesulphonic acid or a naphtalene-sulphonic acid/forrnaldehyde condensation product. Also suitable are the corresponding phosphates, e.g. salts of phosphoric acid ester and an adduct of p-nonylphenol with ethylene and/or propylene oxide, or phospholipids. Suitable phospholipids for this purpose are the natural (originating from animal or plant cells) or synthetic phospholipids of the cephalin or lecithin type such as

e.g. phosphatidylethanolamine, phosphatidylserine, phosphatidylglycerine, lysolecithin, caxdiolipin, dioctanylphosphatidyl-choline, dipalmitoylphoshatidyl -choline and their mixtures.

Suitable non-ionic surfactants include polyethoxylated and polypropoxylated derivatives of alkylphenols, fatty alcohols, fatty acids, aliphatic amines or amides containing at least 12 carbon atoms in the molecule, alkylarenesulphonates and dialkylsulphosuccinates, such as polyglycol ether derivatives of aliphatic and cycloaliphatic alcohols, saturated and unsaturated fatty acids and alkylphenols, said derivatives preferably containing 3 to 10 glycol ether groups and 8 to 20 carbon atoms in the (aliphatic) hydrocarbon moiety and 6 to 18 carbon atoms in the alkyl moiety of the alkylphenol. Further suitable non-ionic surfactants are water-soluble adducts of polyethylene oxide with poylypropylene glycol, ethylenediaminopolypropylene glycol containing 1 to 10 carbon atoms in the alkyl chain, which adducts contain 20 to 250 ethyleneglycol ether groups and/or 10 to 100 propyleneglycol ether groups. Such compounds usually contain from I to 5 ethyleneglycol units per propyleneglycol unit. Representative examples of non-ionic surfactants are nonylphenol -polyethoxyethanol, castor oil polyglycolic ethers, polypropylene/polyethylene oxide adducts, tributylphenoxypolyethoxyethanol, polyethyleneglycol and octylphenoxypolyethoxyethanol. Fatty acid esters of polyethylene sorbitan (such as polyoxyethylene sorbitan trioleate), glycerol, sorbitan, sucrose and pentaerythritol are also suitable non-ionic surfactants. Suitable cationic surfactants include quaternary ammonium salts, particularly halides, having 4 hydrocarbon radicals optionally substituted with halo, phenyl, substituted phenyl or hydroxy; for instance quaternary ammonium salts containing as N-substituent at least one C8C22 alkyl radical (e.g. cetyl, lauryl, palmityl, myristyl, oleyl and the like) and, as further substituents, unsubstituted or halogenated lower alkyl, benzyl and/or hydroxy-lower alkyl radicals.

A more detailed description of surface-active agents suitable for this purpose may be found for instance in "McCutcheon's Detergents and Emulsifiers Annual" (MC Publishing Crop., Ridgewood, New Jersey, 1981), "Tensid-Taschenbucw ¹ , 2 d ed. (Hanser Verlag, Vienna, 1981) and "Encyclopaedia of Surfactants, (Chemical Publishing Co., New York, 1981).

Compounds of the invention and their physiologically acceptable salts (hereafter collectively referred to as the active ingredients) may be administered by any route appropriate to the condition to be treated, suitable routes including oral, rectal, nasal, topical (including ocular,

buccal and sublingual), vaginal and parenteral (including subcutaneous, intramuscular, intravenous, intradermal, intrathecal and epidural). The preferred route of administration may vary with for example the condition of the recipient.

While it is possible for the active ingredients to be administered alone it is preferable to present them as pharmaceutical formulations (or compositions). The formulations, both for veterinary and for human use, of the present invention comprise at least one active ingredient, as above described, together with one or more pharmaceutically acceptable carriers therefore and optionally other therapeutic ingredients. The carrier(s) optimally are "acceptable" in the sense of being compatible with the other ingredients of the formulation and not deleterious to the recipient thereof. The formulations include those suitable for oral, rectal, nasal, topical (including buccal and sublingual), vaginal or parenteral (including subcutaneous, intramuscular, intravenous, intradermal, intrathecal and epidural) administration. The formulations may conveniently be presented in unit dosage form and may be prepared by any of the methods well known in the art of pharmacy. Such methods include the step of bringing into association the active ingredient with the carrier which constitutes one or more accessory ingredients. In general the formulations are prepared by uniformly and intimately bringing into association the active ingredient with liquid carriers or finely divided solid carriers or both, and then, if necessary, shaping the product. Formulations of the present invention suitable for oral administration may be presented as discrete units such as capsules, cachets or tablets each containing a predetermined amount of the active ingredient; as a powder or granules; as solution or a suspension in an aqueous liquid or a non-aqueous liquid; or as an oil-in-water liquid emulsion or a water-in-oil liquid emulsion. The active ingredient may also be presented as a bolus, electuary or paste. A tablet may be made by compression or molding, optionally with one or more accessory ingredients. Compressed tablets may be prepared by compressing in a suitable machine the active ingredient in a free-flowing form such as a powder or granules, optionally mixed with a binder, lubricant, inert diluent, preservative, surface active or dispersing agent. Molded tablets may be made by molding in a suitable machine a mixture of the powdered compound moistened with an inert liquid diluent. The tablets may optionally be coated or scored and may be formulated so as to provide slow or controlled release of the active ingredient therein. For infections of the eye or other external tissues e.g. mouth and skin, the formulations are optionally applied as a topical ointment or cream containing the active ingredient(s) in an

amount of, for example, 0.075 to 20% w/w (including active ingredient(s) in a range between 0.1% and 20% in increments of 0.1% w/w such as 0.6% w/w, 0.7% w/w, etc), preferably 0.2 to 15% w/w and most preferably 0.5 to 10% w/w. When formulated in an ointment, the active ingredients may be employed with either a paraffinic or a water-miscible ointment base. Alternatively, the active ingredients may be formulated in a cream with an oil-in-water cream base. If desired, the aqueous phase of the cream base may include, for example, at least 30% w/w of a polyhydric alcohol, i.e. an alcohol having two or more hydroxyl groups such as propylene glycol, butane 1,3-diol, mannitol, sorbitol, glycerol and polyethylene glycol (including PEG400) and mixtures thereof. The topical formulations may desirably include a compound which enhances absorption or penetration of the active ingredient through the skin or other affected areas. Examples of such dermal penetration enhancers include dimethylsulfoxide and related analogs.

The oily phase of the emulsions of this invention may be constituted from known ingredients in a known manner. While the phase may comprise merely an emulsifier (otherwise known as an emulgent), it desirably comprises a mixture of at least one emulsifier with a fat or an oil or with both a fat and an oil. Optionally, a hydrophilic emulsifier is included together with a lipophilic emulsifier which acts as a stabilizer. It is also preferred to include both an oil and a fat. Together, the emulsifier(s) with or without stabilizer(s) make up the so-called emulsifying wax, and the wax together with the oil and fat make up the so-called emulsifying ointment base which forms the oily dispersed phase of the cream formulations.

The choice of suitable oils or fats for the formulation is based on achieving the desired cosmetic properties, since the solubility of the active compound in most oils likely to be used in pharmaceutical emulsion formulations is very low. Thus the cream should optionally be a non-greasy, non-staining and washable product with suitable consistency to avoid leakage from tubes or other containers. Straight or branched chain, mono- or dibasic alkyl esters such as di-isoadipate, isocetyl stearate, propylene glycol diester of coconut fatty acids, isopropyl myristate, decyl oleate, isopropyl palmitate, butyl stearate, 2-ethylhexyl palmitate or a blend of branched chain esters known as Crodamol CAP may be used, the last three being preferred esters. These may be used alone or in combination depending on the properties required. Alternatively, high melting point lipids such as white soft paraffin and/or liquid paraffin or other mineral oils can be used.

Formulations suitable for topical administration to the eye also include eye drops wherein the active ingredient is dissolved or suspended in a suitable carrier, especially an aqueous solvent

for the active ingredient. The active ingredient is optionally present in such formulations in a concentration of 0.5 to 20%, advantageously 0.5 to 10% particularly about 1.5% w/w. Formulations suitable for topical administration in the mouth include lozenges comprising the active ingredient in a flavored basis, usually sucrose and acacia or tragacanth; pastilles comprising the active ingredient in an inert basis such as gelatin and glycerin, or sucrose and acacia; and mouthwashes comprising the active ingredient in a suitable liquid carrier. Formulations for rectal administration may be presented as a suppository with a suitable base comprising for example cocoa butter or a salicylate. Formulations suitable for nasal administration wherein the carrier is a solid include a coarse powder having a particle size for example in the range 20 to 500 microns (including particle sizes in a range between 20 and 500 microns in increments of 5 microns such as 30 microns, .35 microns, etc), which is administered in the manner in which snuff is taken, i.e. by rapid inhalation through the nasal passage from a container of the powder held close up to the nose. Suitable formulations wherein the carrier is a liquid, for administration as for example a nasal spray or as nasal drops, include aqueous or oily solutions of the active ingredient. Formulations suitable for aerosol administration may be prepared according to conventional methods and may be delivered with other therapeutic agents.

Formulations suitable for vaginal administration may be presented as pessaries, tampons, creams, gels, pastes, foams or spray formulations containing in addition to the active ingredient such carriers as are known in the art to be appropriate.

Formulations suitable for parenteral administration include aqueous and non-aqueous sterile injection solutions which may contain anti-oxidants, buffers, bacteriostats and solutes which render the formulation isotonic with the blood of the intended recipient; and aqueous and nonaqueous sterile suspensions which may include suspending agents and thickening agents. The formulations may be presented in unit-dose or multi-dose containers, for example sealed ampoules and vials, and may be stored in a freeze-dried (lyophilized) condition requiring only the addition of the sterile liquid carrier, for example water for injections, immediately prior to use. Extemporaneous injection solutions and suspensions may be prepared from sterile powders, granules and tablets of the kind previously described. Preferred unit dosage formulations are those containing a daily dose or unit daily sub-dose, as herein above recited, or an appropriate fraction thereof, of an active ingredient. It should be understood that in addition to the ingredients particularly mentioned above the formulations of this invention may include other agents conventional in the art having regard

to the type of formulation in question, for example those suitable for oral administration may include flavoring agents.

Compounds of the invention can be used to provide controlled release pharmaceutical formulations containing as active ingredient one or more compounds of the invention ("controlled release formulations") in which the release of the active ingredient can be controlled and regulated to allow less frequency dosing or to improve the pharmacokinetic or toxicity profile of a given invention compound. Controlled release formulations adapted for oral administration in which discrete units comprising one or more compounds of the invention can be prepared according to conventional methods.

Additional ingredients may be included in order to control the duration of action of the active ingredient in the composition. Control release compositions may thus be achieved by selecting appropriate polymer carriers such as for example polyesters, polyamino acids, polyvinyl pyrrolidone, ethylene-vinyl acetate copolymers, methylcellulose, carboxymethylcellulose, protamine sulfate and the like. The rate of drug release and duration of action may also be controlled by incorporating the active ingredient into particles, e.g. microcapsules, of a polymeric substance such as hydrogels, polylactic acid, hydroxymethylcellulose, polyniethyl methacrylate and the other above-described polymers. Such methods include colloid drug delivery systems like liposomes, microspheres, microemulsions, nanoparticles, nanocapsules and so on. Depending on the route of administration, the pharmaceutical composition may require protective coatings. Pharmaceutical forms suitable for injectionable use include sterile aqueous solutions or dispersions and sterile powders for the extemporaneous preparation thereof. Typical carriers for this purpose therefore include biocompatible aqueous buffers, ethanol, glycerol, propylene glycol, polyethylene glycol and the like and mixtures thereof.

In view of the fact that, when several active ingredients are used in combination, they do not necessarily bring out their joint therapeutic effect directly at the same time in the mammal to be treated, the corresponding composition may also be in the form of a medical kit or package containing the two ingredients in separate but adjacent repositories or compartments. In the latter context, each active ingredient may therefore be formulated in a way suitable for an administration route different from that of the other ingredient, e.g. one of them may be in the

form of an oral or parenteral formulation whereas the other is in the form of an ampoule for intravenous injection or an aerosol.

The compounds of the invention have been synthesised according to the following general procedures, exemplified with some specific compounds. These procedures can easily be applied by a person skilled in the art to the compounds of the invention.

We have synthesized the compounds using Pd-catalyzed Sonogashira coupling reactions under microwave irradiation and in aqueous solution.

We have successfully obtained, through the fusion method, pure halogenotriazole (more in particular bromotriazole) compounds (Scheme 1), respectively. Although direct alkylation method yielded the chlorotriazole compounds satisfactorily, it yielded the bromotriazole compounds with the unseperable chlorotriazole compounds as impurities. AU the synthesized bromo- and chloro-triazole compounds are important substrate for further Pd-catalyzed coupling reactions, and they have been characterized for the compositions and structures by NMR, MS and X-ray analysis. The required compound, 5-halogeno-l-[(2- hydroxyethoxy)methyl]-l,2,4-triazole-3-carboxamide, was purified by column purification from other side-products.

Scheme 1: Synthesis of halogenotriazole (bromotriazole and chlorotriazole) compounds

TsOH, 160 deg, in vacuo

X = Br, Cl

The compounds with a methyl-ester can easily be changed in a carboxamide by using CH3OH/NH3 as exemplified herein. Subsequently, the final compounds of the invention were obtained by employing Sonogashira reactions under microwave irradiation and in aqueous

solution (Scheme 2 - X is Cl or Br). Good to excellent results were obtained under the optimized reaction conditions.

Scheme 2

Sonogashira microwave irradiation

The compounds of the invention can be prepared while using the procedures described herein and a series of chemical reactions well known to those skilled in the art, altogether making up the process for preparing said compounds and exemplified further. The processes described further are only meant as examples and by no means are meant to limit the scope of the present invention.

EXAMPLES

The following examples illustrate the present invention without being limited thereto. Part A represents the preparation of the triazole acyclonucleoside compounds whereas Part B represents the pharmacological examples. Analoguous compounds of the ones specifically mentioned herein are synthesised in the same fashion as in the foregoing schemes and following examples by varying the starting materials, intermediates, solvents and conditions as will be known by those skilled in the art.

AC-I AC-2 AC-3 AC-4

AC-17 AC-18 AC-19 AC-20

PART A: PREPARATION OF THE COMPOUNDS OF THE INVENTION

General Procedures used for the preparation of all the exemplified compounds as described herein. ,

All the terminal alkynes and catalysts were purchased from Acros or Lancaster. The microwave assisted reactions were performed on an Initiator™ Creator produced by Biotage. The ¹ H NMR spectra were recorded at 300 or 600 MHz and the ¹³ C NMR spectra were recorded at 75 or 150 MHz, respectively, on Varian Mercury- VX300 and Varian Inova-600 spectrometers. The chemical shifts were recorded in parts per million (ppm) with TMS as the internal reference. FAB and ESI mass spectra were determined using ZAB-HF-3F and Finnigan LCQ Advantage mass spectrometers, respectively: High resolution mass spectra were obtained by Matrix-assisted laser desorption/ionization mass spectrometry (MALDI-MS) using an IonSpec 4.7 Tesla Fourier Transform Mass Spectrometer. All the compounds were purified by performing flash chromatography on silica gel (200-300 mesh).

The terminal alkynes (0.24 mmol), tetrakis(triphenylphosphine)palladium(0) (11.6 rng, 0.01 mmol), CuI (2.2 mg 0.01 mmol), Li ₂ CO ₃ (30.5 mg, 0.4 mmol) and 5-bromo-l-[(2- hydroxyethoxy)methyl]-l,2,4-triazole-3-carboxamide (0.2 mmol) were suspended in 2.8 mL of dioxane / H ₂ O (3/1) under argon. The vessel was sealed and irradiated at 100 ⁰ C for 25 min, and then cooled to room temperature. The reaction mixture was concentrated under reduced pressure and the crude residue was purified by flash chromatography on silica gel

(CH ₂ Cl ₂ / CH ₃ OH, 20:1). The purified material was dried in vacuo to afford the corresponding αcyc/onucleoside product (AC 1-4).

Methyl S-bromo-l-P^.S-tri-O-acetyl-β-D-riboturanosyη-l^^-triazole -S-carboxylate (92.8 mg, 0.2 mmol) or methyl 5-bromo-l-[2,3,5-tri-(9-aceryl-β-D-ribofuranosyl]-l,2,4-tri azole-3- carboxylate (92.8 mg, 0.2 mmol) and the terminal alkynes (0.2 mmol), tetrakis(triphenylphosphine)palladium(0) (11.6 mg, 0.01 mmol), CuI (3.9 mg 0.02 mmol), triethylamine (0.4 mL, 2.9 mmol) were suspended in 3 mL of fresh distilled MeCN under argon. The vessel was sealed and irradiated at 100 °C for 25 min, and then cooled to room temperature. The reaction mixture was concentrated under reduced pressure and the crude residue was purified by flash chromatography on silica gel (petroleum ether: ethyl acetate, 2:1). The purified material was dried in vacuo to afford the corresponding πέønucleoside product.

EXAMPLE 1: Preparation of 5-Phenylethvnyl-l-[r2-hvdroxyethoxy ^' )methvl]-1.2,4-triazole-3- carboxamide (AC-H

Reaction of 5-bromo-l-[(2-hydroxyethoxy)methyl]-l,2,4-triazole-3-carboxa mide (26.5 mg, 0.1 mmol) according to the general procedure afforded 28.4 mg (99 %) of product, isolated as white solid. ¹ H NMR (300 MHz, DMSO-d,j): δ 8.06 (br s, IH, -C(O)NH), 7.73-7.75 (m, 3H, - C(O)NH and ArH), 7.50-7.58 (m, 3η, ArH), 5.75 (s, 2η, H-I '), A.I 6 (br s, IH, -OH), 3.63 (t, J = 5.1 Hz, 2H, H-2 '), 3.51-3.53 (m, 2H ₅ H-3 J, ¹³ C NMR (150 MHz, DMSO-J ₆ ): δ 160.4, 157.6, 140.6, 132.8, 131.5, 129.8, 120.1, 97.6, 78.8, 75.6, 72.1, 60.5; FAB-MS: m/z 287 [M+H] ⁺ , 309 [M+Na] ⁺ ; HRMS: calcd. for C ₁₄ H ₁₅ N ₄ O ₃ ⁺ 287.1139. Found 287.1148. IR: 2232.7 cm ^"1 (-C≡C-).

EXAMPLE 2: Preparation of 5-[r4-Fluorophenyl)ethvnyl]-l-rr2-hvdroxyethoxy)methyl ^" )- 1.2,4-triazole-3 -carboxamide (AC-2)

Reaction of 5 -bromo-l-[(2-hydroxyethoxy)methyl]-l,2,4-triazole-3 -carboxamide (53.8 mg, 0.2 mmol) according to the general procedure afforded 53.2 mg (86 %) of product, isolated as white solid. ¹ H NMR (300 MHz, DMSO-^): δ 8.07 (br s, IH, -C(O)NH), 7.80-7.85 (m, 2η, ArH), 7.77 (br s, 1η, -C(O)NH), 7.37-7.42 (m, 2η, ArH), 5.75 (s, 2H, H-I \ 4.78 (br s, IH, - OH), 3.62 (t, J= 4.8 Hz, 2H, H-2 '), 3.51-3.52 (m, 2H, H-3 '); ¹³ C NMR (75 MHz, OMSO-d ₆ ): δ 163.9 (d, ¹ JcF = 249.1 Hz), 160.4, 157.6, 140.5, 135.5 (d, ³ Jc _F = 8.6 Hz), 117.2 (d, ² Jo? =

23.4 Hz), 116.6, 96.6, 78.8, 75.5, 72.1, 60.5; FAB-MS: m/z 305 [M+H] ⁺ , 327 (M+Naf; HRMS: calcd. for C ₁₄ H ₁₄ FN ₄ O ₃ ⁺ 305.1044. Found 305.1048; IR: 2230.09 cm ^"1 (-C≡C-).

EXAMPLE 3: Preparation of 5-rfa-TolvDethvnyl1-l-rr2-hvdroxyethoxy)methyll-1.2.4- triazole-3-carboxamide (AC-3)

Reaction of 5-bromo-l-[(2-hydroxyethoxy)methyl]-l,2,4-triazole-3-carboxa mide (54.2 mg, 0.2 mmol) according to the general procedure afforded 55.5 mg (90 %) of product, isolated as white solid. ¹ H NMR (300 MHz, DMSO-^): δ 8.06 (br s, IH, -C(O)NH), 7.76 (br s, IH, - C(O)NH), 7.63 (d, J= 7.8 Hz, 2H, ArH) ₅ 7.34 (d, J= 8.1 Hz ₅ 2H, ArH), 5.73 (s, 2η, H-I % 4.77 (t, J= 4.8 Hz, -OH), 3.62 (t, J= 4.4 Hz, 2H, H-2 % 3.50-3.53 (m, 2H, H-3 % 2.38 (s, 3H, -CH ₅ ); ¹³ C NMR (150 MHz, CDCl ₃ ): δ 160.7, 156.4, 141.5, 141.4, 132.4, 129.7, 116.9, 99.1, 78.6, 73.9, 72.0, 61.6, 22.0; FAB-MS: m/z 301 [M+H] ⁺ , 323 [M+Na] ⁺ ; HRMS: calcd. for C15H17N4O3+ 301.1295. Found 301.1304; IR: 2229.15 cm ^"1 (-C≡C-).

EXAMPLE 4: Preparation of 5-r(2-methyl-l-buten)ethvnyll-l-[r2-hvdroxyethoxy)methyll- 1.2,4-triazole-3-carboxamide fAC-4)

Reaction of 5-bromo-l-[(2-hydroxyethoxy)methyl]-l,2,4-triazole-3-carboxa mide (53.6 mg, 0.2 mmol) according to the general procedure afforded 19.3 mg (38 %) of the required product, isolated as colorless oil. ¹ H NMR (300 MHz, DMSO-^): δ 8.03 (br s, IH, - C(O)NH), 7.73 (br s, 1η, -C(O)NH), 5.68-5.69 (m, 2η, CH ₂ =C-), 5.63 (s, 2H, H-I '), 4.75 (t, J = 5.1 Hz, IH, -OH), 3.56 (t, J= 5.4 Hz, 2H, H-2'), 3.46-3.50 (m, 2H ₅ H-3'), 1.99 (s, 3η, - CH ₃ ); ¹³ C NMR (150 MHz, OMSO-d ₆ ): 8 160.4, 157.5, 140.5, 128.1, 124.9, 98.8, 78.7, 74.5, 72.1, 60.4, 22.7; ESI-MS: m/z 251.0 [M+H] ⁺ ; HRMS: calcd. for C ₁₁ H ₁₅ N ₄ O ₃ ⁺ 251.1139. Found 251.1147; IR: 2217.69 cm ^"1 (-C≡C-).

EXAMPLE 5: Preparation of methyl 5-C2-Triflouromethyl-phenylethvnylVl-(23.5-tri-O- acetyl-β-D-ribofuranosylVlH-f 1,2.4] triazole-3-carboxylaτe (AC-5)

Reaction of S-bromo-l-P _j SjS-tri-O-acetyl-β-D-ribofuranosylj-l^^-triazole-S-carboxyl ate (92.8 mg, 0.2 mmol) according to the general procedure afforded 76.3 mg (69%) of the required product, isolated as colorless oil. ¹ H NMR (300 MHz, CDCl ₃ ): δ 7.75-7.79 (m, 2H, phenyl-H), 7.59-7.64 (m ₅ 2H, phenyl-H), 6.35 (d, IH, J= 4.5 Hz, H-I'), 5.81-5.84 (m, IH ₃ H- T), 5.67-5.71 (m, IH, H-3'), 4.47-4.58 (m, 2H ₅ H-5') ₅ 4.17-4.23 (m, IH, H-4') ₅ 4.00 (s, 3H, OCH ₃ ), 2.18 (s, 3H, C(O)CH ₃ ), 2.15 (s, 3H, C(O)CH ₃ ), 2.05 (s, 3H, C(O)CH ₃ ); ¹³ C NMR (75

MHz, CDCl ₃ ): δ 170.9, 169.8, 159.5, 155.4, 141.5, 135.0, 132.4, 131.8, 130.7, 126.5, 123.6 (q, ¹ J ₀ F = 271.7 Hz), 118.3, 94.4, 88.7, 81.5, 79.0, 74.2, 71.3, 63.0, 53.1, 20.9, 20.6, 20.4; Maldi-MS: m/z 576.1 [M+Na] ⁺ ; HRMS: calcd. for C ₂₄ H ₂₂ N ₃ O ₉ F ₃ Na ⁺ 576.1200, found 576.1196; IR: 2233.8 cm ^"1 (-C≡C-).

EXAMPLE 6: Preparation of methyl 5-C4-Fluoro-phenylethvnyl)-l--( ^' 2.3.5-tri-O-acetyl-B-D- ribofuranosyl)-lH-[1.2.41 triazole-3-carboxylate (AC-6)

Reaction of S-bromo-l-p^jS-tri-O-acetyl-P-D-ribofuranosylJ-l^^-triazole- S-carboxylate (92.8 mg, 0.2 mmol) according to the general procedure afforded 77.5 mg (82%) of product were obtained, isolated as a colorless oil. ¹ H NMR (300 MHz, CDCl ₃ ): δ 7.60-7.64 (m, 2H, phenyl-H), 7.13 (dd, 2H, ³ J _HF = 9.0 Hz, ³ J _m = 8.7 Hz, phenyl-H), 6.26 (d, IH, J= 3.3 Hz, H- 1'), 5.85-5.88 (m, IH, R-T), 5.73-5.76 (m, IH, H-3'), 4.46-4.52 (m, 2H, H-5'), 4.18-4.21 (m, IH, H-4'), 3.99 (s, 3H, -OCH ₃ ), 2.15 (s, 3H, -C(O)CH ₃ ), 2.14 (s, 3H, -C(O)CH ₃ ), 2.13 (s, 3H, -C(O)CH ₃ ); ¹³ C NMR (150 MHz, CDCl ₃ ): δ 170.8, 169.6, 169.4, 163.9 (d, ¹ Jc _F = 252.2 Hz), 159.5, 155.1, 141.7, 134.7 (d, ³ J _C F = 8.6 Hz), 116.4 (d, ² JoT = 22.4 Hz), 97.9, 89.0, 81.4, 74.4, 74.0, 71.1, 62.9, 53.0, 20.8, 20.7, 20.6; Maldi-MS: m/z 526.1 [M+Naf; HRMS: calcd. for C ₂₃ H ₂₂ N ₃ O ₉ FNa ⁺ 526.1232, found 526.1242; IR: 2228.5 cm ^"1 (-C≡C-).

EXAMPLE 7: Preparation of methyl 5-(Thiophen-3-yl ethvnyl)-l-C2.3.5-tri-O-acetyl-β-D- ribofuranosylVlH-ri.2.41 ttiazole-3-carboχylate (AC-I)

Reaction of 5-bromo-l-[2,3,5-tri-O-acetyl-β-D-ribofuranosyl]-l,2,4-tria zole-3-carboxylate (92.8 mg, 0.2 mmol) according to the general procedure afforded 77.6 mg (89%) of product were obtained, isolated as a colorless oil. ¹ H NMR (300 MHz, CDCl ₃ ): δ 7.78 (d, IH, J= 1.5 Hz, thiphenyl-H), 7.37-7.40 (m, IH, thiophenyl-H), 7.28 (s, IH, thiophenyl-H), 6.27 (d, IH, J = 3.6 Hz, H-I'), 5.85-5.88 (m, IH, H-2'), 5.72-5.75 (m, IH, H-3'), 4.48-4.54 (m, 2H, H-5'), 4.11-4.22 (m, IH, H-4'), 3.99 (s, 3H, -OCH ₃ ), 2.14 (s, 9H, -C(O)CH ₃ ); ¹³ C NMR (150 MHz, CDCl ₃ ): δ 170.9, 169.7, 169.4, 159.5, 155.1, 141.9, 132.9, 129.9, 126.6, 119.2, 94.5, 89.0, 81.4, 74.4, 73.9, 71.1, 63.0, 53.0, 20.8, 20.7; Maldi-MS: m/z 492 [M+H] ⁺ ; HRMS: calcd. for C ₂ IH ₂₂ N ₃ O ₉ S ⁺ 492.1071, found 492.1062; IR: 2225.1 cm ^{" 1} C-OsC-).

EXAMPLE 8: Preparation of methyl 5-d-Cvclopentanoi ethvnylVl-(2.3.5-tιi-O-acetyl-β-D- ribofuranosylVlH-π .2.41 triazole-3-carboχylate (AC-8^:

Reaction of S-bromo-l-PjS^-tri-O-acetyl-β-D-ribofuranosyy-l^^-triazole- S-carboxylate (92.8 mg, 0.2 mmol) according to the general procedure afforded 87.7 mg (89%) of product were obtained, isolated as a colorless oil. ¹ H NMR (300 MHz, CDCl ₃ ): δ 6.20 (d, IH, J= 2.4 Hz ₅ H-I'), 5.74-5.77 (m,.lH, H-2'), 5.66-5.70 (m, IH, H-3'), 4.43-4.54 (m, 2H, H-5') ₅ 4.19- 4.24 (m, IH, H-4'), 3.97 (s, 3H, -OCH ₃ ), 3.00 (br s, IH, -OH), 2.14 (s, 9H ₅ -C(O)CH ₃ ), 2.06- 2.08 (m ₅ 4H, cyclopentanyl-H), 1.77-1.93 (m, 4H ₅ cyclopentanyl-H); ¹³ C NMR (75 MHz ₅ CDCl ₃ ): δ 170.9, 169.8, 159.4, 154.6, 141.4, 104.6, 89.I ₅ 81.0, 74.4, 70.8, 68.1, 62.9, 52.9, 42.2, 23.7, 20.7, 20.6; Maldi-MS: m/z 516.2 [M+Na] ⁺ ; HRMS: calcd. for C ₂₂ H ₂₇ N ₃ O ₁₀ Na ⁺ 516.1589, found 516.1586; IR: 2240.8 cm ^"1 (-C=C-).

EXAMPLE 9: Preparation of 5-(4-Methoxy-phenylethvnyl)-l-(2.3.5-tri-Hvdroxy-β-D- ribofuranosyl)-lH-[l,2,4] triazole-3-carboxylic acid amide (αC-9)

Methyl 5-(4-Methoxy-phenylethynyl)-l-(2 ₅ 3 ₅ 5-tri-O-acetyl-β-D-ribofuranosyl)-lH-[l ₅ 2 ₅ 4] triazole-3-carboxylate (0.15 mmol), prepared according to the general procedure, was dissolved in 0.2 M NH ₃ /MeOH and stirred at room temperature for 2 days. Then the solvent was removed and the residue was washed with CH ₂ CI ₂ . 30.6 mg (78%) of required product was obtained, isolated as a white solid. ¹ H NMR (300 MHz ₅ DMSO-^ ₆ ): δ 8.04 (br, IH ₅ - C(O)NH ₂ ), 7.77 (br, IH, -C(O)NH ₂ ), 7.66 (d, 2H ₅ J= 9.0 Hz ₅ phenyl-H), 7.08 (d, 2H, J= 8.7 Hz ₅ phenyl-H), 5.99 (d, IH, J= 4.5 Hz, H-I'), 5.65 (d, IH ₅ J= 6.3 Hz, -OH), 5.30 (d, IH ₅ J= 6.0 Hz, -OH), 4.82 (t, IH ₅ J= 5.4 Hz, -OH), 4.48-4.53 (m, IH ₅ H-2'), 4.21-4.26 (m, IH ₅ H- 3'), 3.95-3.98 (m, IH ₅ H-4') ₅ 3.84 (s, 3H ₅ -OCH ₃ ), 3.43-3.60 (m, 2H ₅ H-5'); ¹³ C NMR (75 MHz ₅ DMSO-J*): δ 161.8, 160.4, 157.6, 141.0, 134.6, 115.5, 111.6, 98.4, 91.1, 86.9, 74.8, 74.4, 71.2, 62.7, 56.2; Maldi-MS: m/z 397 [M+Na] ⁺ ; HRMS: calcd. for C ₁₇ H ₁₈ N ₄ O ₆ Na ⁺ 397.1119, found 397.1119; IR: 2222.1 cm ^{" 1} ^C=C-).

EXAMPLE 10: Preparation of 5-r4-Triflouromethyl-ρhenylethvnylVl-(2.3.5-tri-Hvdroxy-β- D-ribofuranosylVlH-[1.2.4] triazole-3-carboxylic acid amide TAC-IO); Methyl 5-(4-Triflouromemyl-phenylethynyl)-l-(2,3 ₃ 5-tri-O-acetyl-β-D-ribofuranosyl)-lH- [1,2,4] triazole-3-carboxylate (0.15 mmol), prepared according to the general procedure, was dissolved in 0.2 M NH ₃ ZMeOH and stirred at room temperature for 2 days. Then the solvent was removed and the residue was washed with CH ₂ Cl ₂ . 47.7 mg (73%) of required product was obtained, isolated as a white solid. ¹ H NMR (300 MHz, DMSO-cfc): δ 8.09 (br s, IH, - C(O)NH ₂ ), 7.89-7.98 (m, 4H, phenyl-H), 7.82 (br s, IH ₅ -C(O)NH ₂ ), 6.04 (d, IH, J= 4.5 Hz,

H-I'), 5.67 (d, IH, J= 6.0 Hz, -OH) ₅ 5.32 (d, IH, J= 6.0 Hz, -OH), 4.83 (t, IH, J= 5.4 Hz, - OH), 4.50-4.55 (m, IH, H-2'), 4.23-4.28 (m, IH, H-3'), 3.97-4.02 (m, IH, H-4'), 3.44-3.61 (m, 2H, H-5'); ¹³ C NMR (75 MHz, DMSO-^): δ 172.2, 160.3, 157.8, 140.1, 133.7, 131.2 (q, ² J _CF = 32.9 Hz), 126.7, 123.9 (q, ¹ J ₀ F = 272 Hz) , 124.2, 96.0, 91.3, 86.9, 77.3, 74.9, 71.2, 62.6; Maldi-MS: m/z 435 [M+Na] ⁺ ; HRMS: calcd. for Ci ₇ H ₁₅ N ₄ O ₅ F ₃ Na ⁺ 435.0887, found 435.0885; IR: 2232.8 cm^C-C≡C-).

EXAMPLE 11: Preparation of 5-r3-Triflouromethyl-ρhenylethvnylVl-(2,3,5-tri-Hvdroxy-β- D-ribofuranosylVlH-[1.2.4] triazole-3-carboxylic acid amide (AC-11); Methyl 5-(3-Triflourome%l-phenylethynyl)-l-(2,3,5-1ri-0-acetyl-β-D -ribofuranosyl)-lH- [1,2,4] triazole-3-carboxylate (0.15 mmol), prepared according to the general procedure, was dissolved in 0.2 M NH ₃ /Me0H and stirred at room temperature for 2 days. Then the solvent was removed and the residue was washed with CH ₂ Cl ₂ . 31.1 mg (78%) of required product was obtained, isolated as a white solid. ¹ H NMR (300 MHz, DMSO-Jd): δ 8.13 (s, IH, phenyl-H), 8.05 (br s, IH, -C(O)NH ₂ ), 7.95-8.05 (m, 2H, phenyl-H), 7.95 (d, IH, J= 8.1 Hz, phenyl-H), 7.78 (br s, IH, -C(O)NH ₂ ), 6.06 (d, IH, J = 3.9 Hz, H-I'), 5.64 (d, IH, J= 6.0 Hz, -OH), 5.28 (d, IH, J= 5.1 Hz, -OH), 4.81 (t, IH, J= 5.6 Hz, -OH), 4.50-4.52 (m, IH, H-2'), 4.24-4.26 (m, IH, H-3'), 3.98-4.00 (m, IH, H-4'), 3.44-3.59 (m, 2H, H-5'); ¹³ C NMR (150 MHz, DMSO-tfc): δ 160.3, 157.8, 140.2, 136.8, 131.1, 130.6 (d, ² Jc^= 31.8 Hz), 129.3, 128.1, 124.2 (d, ¹ Jc _F = 270.6 Hz), 121.2, 95.9, 91.3, 86.9, 76.5, 74.9, 71.2, 62.7; ESI-MS: m/z 413 [M+Hf; HRMS: calcd. for C ₁₇ H ₁₅ N ₄ O ₅ F ₃ Na ⁺ 435.0887, found 435.0882; IR: 2234.2 cm ^' ^- C=C-).

EXAMPLE 12: Preparation of 5-r4-Fluoro-phenylethvnyl)-l-r2.3.5-tri-Hvdroxy-β-D- ribofuranosyl)-lH-[l,2,4] triazole-3-carboxylic acid amide (AC-12);

Methyl 5-(4-Fluoro-ρhenylethynyl)-l-(2,3,5-tri-O-acetyl-β-D-ribof uranosyl)-lH-[l,2,4] triazole-3-carboxylate (0.15 mmol), prepared according to the general procedure, was dissolved in 0.2 M NH ₃ /Me0H and stirred at room temperature for 2 days. Then the solvent was removed and the residue was washed with CH ₂ Cl ₂ . 41.8 mg (77%) of required product was obtained, isolated as a white solid. ¹ H NMR (300 MHz, DMSO-^): δ 8.06 (br s, IH, - C(O)NH ₂ ), 7.83 (br s, IH, -C(O)NH ₂ ), 7.78-7.80 (m, 2H, phenyl-H), 7.39 (dd, 2H, ³ J _HF = 8.7 Hz, ³ JHH = 8.7 Hz, phenyl-H), 6.00 (d, IH, J= 4.5 Hz, H-I'), 5.64 (d, IH, J= 5.7 Hz, -OH), 5.30 (d, IH, J= 6.0 Hz, -OH), 4.82 (t, IH, J= 6.0 Hz, -OH), 4.48-4.53 (m, IH, H-2'), 4.21-

4.26 (m, IH ₅ H-3'), 3.96-3.98 (m, IH ₅ H-4'), 3.41-3.59 (m ₅ 2H, H-5'); ¹³ C NMR (150 MHz ₅ DMSO-4): δ 162.5, 162.2, 160.3, 157.7, 140.6, 135.5, 117.2 (d, ² J _CF = 22A Hz), 116.4, 96.9, 91.3, 87.0, 75.2, 74.8, 71.2, 62.7; Maldi-MS: m/z 385 [M+Na] ⁺ ; HRMS: calcd. for Ci ₆ H ₁₅ N ₄ O ₅ FNa ⁺ 385.0919, found 385.0917; IR: 2229.4 cm ^"1 (-C≡C-).

EXAMPLE 13: Preparation of 5-r2-Fluoro-phenylethvnylVl-(2.3.5-tri-Hvdroxy-β-D- ribofuranosyl)- IH- [1,2,4] triazole-3-carboxylic acid amide (AC-13):

Methyl 5-(2-Fluoro-ρhenylethynyl> 1 -(2,3 ,5-tri-O-acetyl-β-D-ribofuranosyl)- IH- [1 ,2,4] triazole-3-carboxylate (0.15 mmol), prepared according to the general procedure, was dissolved in 0.2 M NH ₃ ZMeOH and stirred at room temperature for 2 days. Then the solvent was removed and the residue was washed with CH2CI2. 44.0 mg (81%) of required product was obtained, isolated as a white solid. ¹ H NMR (300 MHz, OMSO-d ₆ ): δ 8.07 (br, IH, - C(O)NH), 7.79 (br, IH, -C(O)NH), 7.58-7.66 (m, 3H, phenyl-H), 7.47-7.49 (m, IH, phenyl- H), 6.02 (d, IH, J = 4.5 Hz), 5.65 (d, IH, J = 5.7 Hz, -OH), 5.31 (d, IH, J = 5.7 Hz, -OH), 4.82 (t, IH, J = 5.4 Hz, -OH), 4.48-4.53 (m, IH, H-2'), 4.21-4.26 (m, IH, H-3'), 3.97-3.99 (m, IH, H-4'), 3.34-3.60 (m, 2H, H-5'); ¹³ C NMR (150 MHz, OMSO-d ₆ ) δ 162.8 (d, ¹ JcF = 273 Hz), 160.3, 157.8, 140.3, 132.1 (d, ³ J _CF = 9.6 Hz), 129.3, 121.8, 119.4 (d, ² JcF = 23.0), 119.0 (d, ² JcF= 21.0), 96.3, 91.3, 87.0, 76.0, 74.9, 71.2, 62.7; Maldi-MS: m/z 385 [M+Na] ⁺ ; HRMS: calcd. for C ₁₆ H ₁₅ N ₄ O ₅ FNa ⁺ 385.0919, found 385.0923; IR: 2233.3 cm ⁴ (-C≡C-).

EXAMPLE 14: Preparation of 5-(Thiophen-2-yl ethvnylM-f2,,3..S-tri-Hydroxy-β-D- ribofuranosvD- IH-[1, 2,4] triazole-3-carboxylic acid amide (AC-14);

Methyl 5-(Thiophen-2-yl ethynyl)-l-(2,3,5-rri-O-acetyl-β-D-ribofuranosyl)-lH-[l ,2,4] triazole-3-carboxylate (0.15 mmol), prepared according to the general procedure, was dissolved in 0.2 M NH ₃ ZMeOH and stirred at room temperature for 2 days. Then the solvent was removed and the residue was washed with CH ₂ Cl ₂ . 31.0 mg (85%) of required product was obtained, isolated as a yellow solid. ¹ H NMR (300 MHz, DMSO-dt _f ): δ 8.04 (br s, IH, - C(O)NH ₂ ), 7.91-7.92 (m, IH, thiophene-H), 7.77 (br s, IH, -C(O)NH ₂ ), 7.72-7.73 (m, IH, thiophene-H), 7.23-7.26 (m, IH, thiophene-H), 5.94 (d, IH, J= 5.1 Hz, H-I'), 5.65 (d, IH, J = 5.1 Hz, -OH), 5.30 (d, IH, J= 5.7 Hz, -OH), 4.82 (t, IH, J= 5.9 Hz, -OH), 4.49-4.52 (m, IH, H-2'), 4.22-4.24 (m, IH, H-3'), 3.97-3.98 (m, IH, H-4'), 3.41-3.60 (m, 2H, H-5'); ¹³ C NMR (150 MHz, DMSO-^): δ 160.3, 157.8, 140.5, 136.7, 131.9, 129.0, 119.0, 91.5, 91.2,

86.9, 78.9, 74.7, 71.2, 62.7; ESI-MS: m/z 373.1 [M+Naf; HRMS: calcd. for Ci ₄ H ₁₄ N ₄ O ₅ SNa ⁺ 373.0577, found 373.0585; IR: 2216.9 ran ¹ C-OC-).

EXAMPLE 15: Preparation of 5-(Tbioρhen-3-yl ethvnylVl-f23.5-tri-Hvdroxy-β-D- ribofuranosyl)-lH-[1.2,41 triazole-3-carboxylic acid amide (αC-15);

Methyl 5-(Thioρhen-3-yl ethynyl)-l-(2,3,5-tri-O-acetyl-β-D-ribofuranosyl)-lH-[l,2,4 ] triazole-3-carboxylate (0.15 mmol), prepared according to the general procedure, was dissolved in 0.2 M NH ₃ ZMeOH and stirred at room temperature for 2 days. Then the solvent was removed and the residue was washed with CH ₂ CI ₂ . 37.2 mg (76%) of required product was obtained, isolated as a yellow solid. ¹ H NMR (300 MHz, DMSCMf): δ 8.24 (d, IH, J= 1.5 Hz, thiophenyl-H), 8.03 (br s, IH, -C(O)NH), 7.76-7.78 (m, 2H, thiophenyl-H and - C(O)NH), 7.42 (d, IH, J= 4.5 Hz ₅ thiophenyl-H), 5.98 (d, IH, J= 4.5 Hz, H-I'), 5.65 (d, IH, J= S.I Hz, -OH), 5.30 (d, IH, J= 5.7 Hz, -OH), 4.84 (t, IH ₅ J= 5.6 Hz, -OH) ₅ 4.49-4.54 (m, IH, H-2'), 4.22-4.27 (m, IH, H-3'), 3.96-3.99 (m, IH, H-4'), 3.46-3.61 (m, 2H, H-5'); ¹³ C NMR (150 MHz, DMSCMs): δ 160.4, 157.7, 140.8, 134.6, 130.3, 128.7, 118.8, 93.6, 91.1, 86.9, 74.9, 74.8, 71.2, 62.7; Maldi-MS: m/z 351 [M+H] ⁺ ; HRMS: calcd. for C ₁₄ H ₁₅ N ₄ O ₅ S ⁺ 351.0758, found 351.0760; IR: 2223.6 cm^-C≡C-).

EXAMPLE 16: Preparation of methyl 3-(3-Triflouromethyl-phenylethvnylVl-(2.3.5-tri-O- acetyl-β-D-ribofuranosylVlH-[l,Z4] triazole-5-carboxylate (AC-16);

Reaction of 3-bromo- 1 -[2,3,5-tri-O-acetyl-β-D-ribofuranosyl]- 1 ,2,4-triazole-5-carboxylate (92.8 mg, 0.2 mmol) according to the general procedure afforded 70.8 mg (64%) of product were obtained, isolated as a yellow oil. ¹ H NMR (300 MHz, CDCl ₃ ): δ 7.88 (s, IH, phenyl-H), 7.7-7.79 (m, IH, phenyl-H), 7.66-7.68 (m, IH, phenyl-H), 7.49-7.55 (m, IH, phenyl-H), 6.97 (d, IH, J = 1.5 Hz, H-I'), 5.85-5.88 (m, IH, H-2'), 5.77-5.81 (m, IH, H-3'), 4.44-4.49 (m, 2H, H-5'), 4.16-4.22 (m, IH, H-4'), 4.04 (s, 3H, -OCH ₃ ), 2.16 (s, 3H, -C(O)CH ₃ ), 2.14 (s, 3H, -C(O)CH ₃ ), 2.09 (s, 3H, -C(O)CH ₃ ); ¹³ C NMR (150 MHz, CDCl ₃ ): δ 170.7, 169.8, 169.6, 157.6, 147.6, 145.3, 135.4, 131.4 (q, V _C F = 32.9 Hz), 129.3, 129.1, 126.4, 123.7 (q, ¹ Jc _F = 271 Hz), 122.3, 89.8, 89.2, 80.9, 80.6, 74.6, 70.9. 63.0, 53.8, 20.9, 20.7; Maldi-MS: m/z 576 [M+Na] ⁺ ; HRMS: calcd. for C ₂₄ H ₂₂ N ₃ O ₉ F ₃ Na ⁺ 576.1200, found 576.1187.

EXAMPLE 17: Preparation of methyl 3-(2-Fluoro-phenylethvnylVl-(2.3.5-tri-O-acetyl-β-D- ribofuranosylVlH-[1.2.4] triazole-5-carboxylate (AC-17V

Reaction of S-bromo-l-PjSjS-tri-O-acetyl-β-D-ribofuranosylj-l^^-triazol e-S-carboxylate (92.8 nig, 0.2 mmol) according to the general procedure afforded 64.4 mg (64%) of product were obtained, isolated as a colorless oil. ¹ H NMR (300 MHz, CDCl ₃ ): δ 7.58 (dd, IH, J= 7.8 Hz, 7.8 Hz ₅ phenyl-H), 7.39-7.41 (m, IH, phenyl-H), 7.09-7.18 (m, 2H, phenyl-H), 6.96 (d, IH, J= 2.4 Hz, H-I'), 5.87-5.89 (m, IH ₅ H-2'), 5.76-5.80 (m, IH, H-3'), 4.46-4.50 (m, 2H, H-5'), 4.15-4.21 (m, IH, H-4'), 4.04 (s, 3H, -OCH3), 2.15 (s, 3H, -C(O)CH ₃ ), 2.13 (s, 3H, - C(O)CH ₃ ), 2.11 (s, 3H, -C(O)CH ₃ ); ¹³ C NMR (150 MHz, CDCl ₃ ): δ 170.9, 169.7, 169.6, 163.3 (d, ¹ Jc _F = 252.8 Hz), 157.7, 147.8, 145.3, 134.2, 131.8 (d, ³ JcF= I.9 Hz), 124.3 (d, ⁴ J _CF = 3.4 Hz), 116.0 (d, ² J _CF = 20.3 Hz), 110.1 (d, ² JcF = 14.6 Hz), 89.8, 84.6, 84.0, 81.1, 74.6, 71.0, 62.7, 53.8, 20.9, 20.7.

EXAMPLE 18: Preparation of methyl 3-fThiophen-3-yl ethynylVl-f2.3,5-tri-O-acetyl-β-D- ribofυranosylVlH-[l,2,4] triazole-5-carboxylate (AC-18);

Reaction of S-bromo-l-PjSjS-tri-O-acetyl-β-D-ribofuranosylJ-l^^-triazol e-S-carboxylate (92.8 mg, 0.2 mmol) according to the general procedure afforded 51.1 mg (52%) of product were obtained, isolated as a pale yellow oil. ¹ H NMR (300 MHz, CDCl ₃ ): δ 7.67-7.68 (m, IH, thiophenyl-H), 7.32-7.34 (m, IH, thiophenyl-H), 7.24-7.26 (m, IH, thiophenyl-H), 6.96 (d, IH, J= 1.5 Hz, H-I'), 5.85-5.87 (m, IH, H-2'), 5.77-5.81 (m, IH, H-3'), 4.45-4.49 (m, 2H, H-5'), 4.14-4.21 (m, IH, H-4'), 4.03 (s, 3H, -OCH ₃ ), 2.16 (s, 3H, -C(O)CH ₃ ), 2.13 (s, 3H, - C(O)CH ₃ ), 2.10 (s, 3H, -C(O)CH ₃ ); ¹³ C NMR (75 MHz ₅ CDCl ₃ ): δ 170.8, 169.8, 169.6, 157.7, 148.1, 145.2, 131.5, 130.1, 126.0, 120.5, 89.7, 86.5, 80.9, 79.0, 74.6, 71.0, 63.0, 53.8, 20.9, 20.7; Maldi-MS: m/z 514 [M+Na] ⁺ ; HRMS: calcd. for C ₂₁ H ₂₁ N ₃ O ₉ SNa ⁺ 514.0890, found 514.0876; IR: 2228.8 cm ^' ^-C≡C-).

EXAMPLE 19: Preparation of methyl 3-ri-methyl-lH-imidazole-4-ethvnylVl-(2.3.5-tri-O- acetyl-β-D-ribofuranosyl)-lH-| ^" l,2,4] triazole-5-carboxylate (AC-19): Reaction of 3-bromo-l-[2,3,5-tri-<9-acetyl-β-D-ribofuranosyl]-l,2,4- triazole-5-carboxylate (92.8 mg, 0.2 mmol) according to the general procedure afforded 59.6 mg (61%) of product were obtained, isolated as a pink oil. ¹ H NMR (300 MHz, CDCl ₃ ): δ 7.73 (s, IH, imidazole- H),7.49 (s, IH, imidazole-H), 6.97 (d, IH, J= 1.2 Hz, H-I'), 5.84-5.86 (m, IH, H-2'), 5.74- 5.78 (m, lH,H-3'), 4.44-4.49 (m, 2H, H-5'), 4.15-4.21 (m, IH, H-4'), 4.04 (s, 3H, -OCH ₃ ), 3.77 (s, 3H, -NCH ₃ ), 2.16 (s, 3H, -C(O)CH ₃ ), 2.14 (s, 3H, -C(O)CH ₃ ), 2.08 (s, 3H, -

C(O)CH ₃ ); ¹³ C NMR (75 MHz, CDCl ₃ ): δ 170.7, 169.8, 169.6, 157.6, 147.7, 145.3, 139.4, 137.2, 114.7, 89.8, 86.7, 80.9, 79.3, 74.6, 70.9, 63.0, 53.2, 32.6, 20.9, 20.7, 20.7; Maldi-MS: m/z 490 [MH-H] ⁺ ; HRMS: calcd. for C ₂₁ H ₂₄ N ₅ O ₉ ⁺ 490.1567, found 490.1548; IR: 2228.4 cm ^"

¹ OOC-).

EXAMPLE 20: Preparation of methyl 3-α-Cvcloρentanol ethvnyl)-l-(2.3.5-tri-O-acetyl-β-D- ribofuranosylVlH-[l,2.,41 triazole-5-carboxylate (AC-20);

Reaction of 3-bromo-l-[2,3,5-tri-O-acetyl-β-D-ribofuranosyl]-l,2,4-tria zole-5-carboxylate (92.8 mg, 0.2 mmol) according to the general procedure afforded 77.9 mg (79%) of product were obtained, isolated as a colorless oil. ¹ H NMR (300 MHz ₅ CDCl ₃ ): δ 6.92 (d, IH, J= 2.4 Hz, H-I'), 5.80-5.83 (m, IH, H-2'), 5.72-5.76 (m, IH, H-3'), 4.43-4.46 (m, 2H, H-5'), 4.12- 4.19 (m, IH, H-4'), 4.01 (s, 3H, -OCH ₃ ), 2.47 (br, IH, -OH), 2.14 (s, 3H, -C(O)CH ₃ ), 2.12 (s, 3H, -C(O)CH ₃ ), 2.08 (s, 3H, -C(O)CH ₃ ), 1.99-2.05 (m, 4H, cyclopentanyl-H), 1.75-1.87 (m, 4H, cyclopentanyl-H); ¹³ C NMR (75 MHz, CDCl ₃ ): δ 170.9, 169.8, 169.6, 157.6, 147.7, 145.1, 95.5, 89.7, 80.9, 74.6, 74.4, 73.2, 71.0, 63.0, 53.8, 42.3, 23.7, 20.9, 20.7; Maldi-MS: m/z 516 [M+Na] ⁺ ; HRMS: calcd. for C ₂₂ H ₂₇ N ₃ O ₁₀ Na ⁺ 516.1589, found 516.1581.

EXAMPLE 21: Preparation of 3-r2-Triflourometliyl-ρhenylethvnyl)-l-r2.3.,5-tri-O-acetyl -β- D-ribofuranosvO- IH- [1.2,4] triazole-5-carboxylic acid amide CAC-21); Methyl 3 -(2-Triflouromethyl-phenylethynyl)- 1 -(2,3 ,5-tri-O-acetyl-β-D-ribofuranosyl)- 1 H- [1,2,4] triazole-5-carboxylate (0.15 mmol), prepared according to the general procedure, was dissolved in 0.2 M NH ₃ ZMeOH and stirred at room temperature for 2 days. Then the solvent was removed and the residue was washed with CH ₂ Cl ₂ . 30.1 mg (73%) of required product was obtained, isolated as a white solid. ¹ H NMR (300 MHz, OM$O-d ₆ ): δ 8.50 (br, IH, - C(O)NH), 8.19 (br, IH, -C(O)NH), 7.89-7.95 (m, 2H, phenyl-H), 7.70-7.82 (m, 2H, phenyl- H), 6.77 (d, IH, J = 3.6 Hz, H-I'), 5.52 (d, IH, J= 5.7 Hz, -OH), 5.20 (d, IH, J= 6.0 Hz, - OH), 4.78 (t, IH, J= 5.7 Hz, -OH), 4.42-4.47 (m, IH, H-2'), 4.20-4.25 (m, IH, H-3'), 3.91- 3.96 (m, IH, H-4'), 3.42-3.62 (m, 2H, H-5'); ¹³ C NMR (75 MHz, DMSO-^): δ 158.5, 149.2, 145.4, 135.5, 133.6, 131.2, 130.9 (q, ² J _C F = 30.3 Hz), 127.0, 124.1 (q, ¹ JcF = 271.7 Hz), 118.8, 91.5, 86.2, 85.6, 85.4, 74.9, 71.3, 62.7; Maldi-MS: m/z 435 [M+Na] ⁺ ; HRMS: calcd. for Ci ₇ H ₁₅ N ₄ O ₅ F ₃ Na ⁺ 435.0886, found 435.0877; IR: 2234.6 cm ^' ^-C≡C-).

EXAMPLE 22: Preparation of 3-(4-Chloro-phenyletlivnylVl-r23.5-tri-Hvdroxy-β-D- ribofuranosylVlH-l ^' 1.,2.,41 triazole-5-carboxylic acid amide (AC-22);

Methyl 3-(4-Chloro-ρhenylethynyl)-l-(2,3,5-tri-O-acetyl-β-D-ribof uranosyl)-lH-[l,2,4] triazole-5-carboxylate (0.15 mmol), prepared according to the general procedure, was dissolved in 0.2 M NH ₃ MeOH and stirred at room temperature for 2 days. Then the solvent was removed and the residue was washed with CH ₂ Cl ₂ . 33.6 mg (77%) of required product was obtained, isolated as a white solid. ¹ H NMR (300 MHz, DMSO-J ₆ ): δ 8.48 (br s, IH, - C(O)NH) ₅ 8.17 (br s, IH, -C(O)NH), 7.68 (d, 2H, J = 8.1 Hz, phenyl-H), 7.55 (d, 2H, J = 8.1 Hz, phenyl-H), 6.76 (d ₃ IH, J = 3.6 Hz, H-I'), 5.52 (d, IH, J = 6.0 Hz, OH), 5.19 (d, IH, J = 6.0 Hz, OH), 4.78 (t, IH, J = 6.0 Hz, OH), 4.40-4.45 (m, IH ₅ H-2'), 4.19-4.23 (m, IH, H-3'), 3.90-3.92 (m, IH, H-4'), 3.40-3.59 (m ₅ 2H, H-5'); ¹³ C NMR (75 MHz, DMSO-^): δ 163.3, 153.8, 150.4, 140.4, 139.0, 134.6, 124.6, 96.2, 93.7, 90.9, 86.4, 79.7, 76.0, 67.5; Maldi-MS: m/z 401 [M+Naf; HRMS: calcd. for C ₁₆ H ₁₅ N ₄ O ₅ ClNa ⁺ 401.0623, found 401.0625; IR: 2234.9 cm ^{" 1} O-C=C-).

EXAMPLE 23: Preparation of 3-(Thiophen-3-yl ethvnviπ-(2.3.5-tri-Hvdroxy-β-D- ribofuranosyl)-lH-ri-,2,4] triazole-5-carboxylic acid amide (AC-23);

Methyl 3-(Thioρhen-3-yl ethynyl)-l-(2,3,5-tri-O-acetyl-β-D-ribofuranosyl)-lH-[l,2,4 ] triazole-5-carboxylate (0.15 mmol), prepared according to the general procedure, was dissolved in 0.2 M NH ₃ /Me0H and stirred at room temperature for 2 days. Then the solvent was removed and the residue was washed with CH ₂ Cl ₂ . 40.5 mg (76%) of required product was obtained, isolated as a white solid. ¹ H NMR (300 MHz, DMSO-J ₀ ): δ 8.48 (br s, IH, - C(O)NH) ₅ 8.17 (br s, IH ₅ -C(O)NH) ₅ 8.14 (d, IH, J = 1.8 Hz, thiophenyl-H), 7.72-7.74 (m, IH, thiophenyl-H), 7.38 (d, IH, J = 4.8 Hz ₅ thiophenyl-H), 6.77 (d, IH, J = 3.0 Hz, H-I'), 5.51 (d, IH, J = 5.1 Hz, OH), 5.19 (d, IH, J = 6.0 Hz, OH), 4.78 (t, IH, J = 5.4 Hz, OH), 4.41- 4.45 (m, IH, H-2'), 4.12-4.26 (m, IH, H-3'), 3.90-3.95 (m, IH, H-4'), 3.43-3.63 (m, 2H, H- 5'); ¹³ C NMR (75 MHz, DMSO-J _d ): δ 158.6, 148.9, 145.9, 133.1, 128.2, 119.8, 91.4, 86.1, 85.9, 80.2, 74.9, 71.3, 62.7; Maldi-MS: m/z 373 [M+Naf; HRMS: calcd. for C14H14N4O5SNa ⁺ 373.0577, found 373.0587; IR: 2234.0 cm ^' ^-C≡C-).

Other compounds according to the invention were prepared and can be prepared as described for the above examples.

PART B: METHODOLOGY FOR AND RESULTS OF THE DETERMINATION OF ANTIVIRAL AND CYTOSTATIC ACTIVITY

EXAMPLE 24: Determination and investigation of the anti-HCV activity

Huh-5-2 cells [a cell line with a persistent HCV replicon I3891uc-ubi-neo/NS3-375.1; replicon with firefly luciferase-ubiquitin-neomycin phosphotransferase fusion protein and EMCV-IRES driven NS3-5B HCV polyprotein] was cultured in RPMI medium (Gibco) supplemented with 10% fetal calf serum, 2mM L-glutamine (Life Technologies), Ix nonessential amino acids (Life Technologies); 100 IU/ml penicillin and 100 ug/ml streptomycin and 250 ug/ml G418 (Geneticin, Life Technologies). Cells were seeded at a densitiy of 7000 cells per well in 96 well View Plate™ (Packard) in medium containing the same components as described above, except for G418. Cells were allowed to adhere and proliferate for 24 hr. At that time, culture medium was removed and serial dilutions of the test compounds were added in culture medium lacking G418. Interferon alfa 2a (500 RT) was included as a positive control. Plates were further incubated at 37°C and 5% CO ₂ for 72 hours. Replication of the HCV replicon in Huh-5 cells results in luciferase activity in the cells. Luciferase activity is measured by adding 50 μl of 1 x Glo-lysis buffer (Promega) for 15 minutes followed by 50 ul of the Steady-Glo Luciferase assay reagent (Promega) . Luciferase activity is measured with a luminometer and the signal in each individual well is expressed as a percentage of the untreated cultures. Parallel cultures of Huh-5-2 cells, seeded at a density of 7000 cells/ well of classical 96- well eel culture plates (Becton-Dickinson) are treated in a similar fashion except that no Glo-lysis buffer or Steady-Glo Luciferase reagent is added. Instead the density of the culture is measured by means of the MTS method (Promega).

EXAMPLE 25 - Anti-viral activity

The results of the testing of the compounds of the invention in the HCV-Huh-5-2 replicon cell assay described above are provided in Table 1 hereunder. Most of the active compounds yielded an inhibition of between 90% and 100%, while ribavirin only yielded a maximal inhibition of around 70%.

Table 1 : Antiviral Activities of compounds of the invention as shown in Tables 1 and 2 on HCV Subgenomic Replicon Replication in Huh-5-2 Cells

Anti-HCV activity ³

compd CC50 (μM) EC ₅₀ ⁰ (μM) SI ^d

AC-I >50 19 >2.6

AC-2 >50 25 >2

AC-3 >50 16 >3.1

AC-5 >50 39 >1.3

AC-6 >50 33 >1.5

AC-7 >50 9 >5.6

AC-8 >50 24.7±1.5 >2.0

AC-9 >50 29±2.7 >1.8

AC-IO 34±4 7.25±0.75 4.7

AC-Il >50 12 >4.2

AC-12 >50 39 >1.3

AC-13 >50 36 >1.4

AC-14 >50 30 >1.7

AC-15 >50 22±14 >1.4

AC-16 >50 39±1.0 >1.3

AC-17 >50 33 >1.5

AC-18 >50 4 >12.5

AC-19 >50 25±5.6 >1.7

AC-20 >50 28.3±0.3 >1.8

AC-21 >50 36 >1.4

AC-22 >50 27 >1.8

AC-23 >50 24 >2.1

AC-24 31 5 6.2

AC-25 25 6 4.2

AC-26 22 3 7.3

AC-27 26 5 5.2

AC-28 20 5 4

AC-29 24 6 4

Ribavirin >140 85 1.7

"Interferon α-2b at 10.000 units/well reduced the signal in the viral RNA (luciferase) assay to background levels; without any cytostatic activity. * Cytotoxic concentration CC50: concentration required to inhibit the proliferation of exponentially growing Huh-5-2 cells by 50%.. ^c Effective concentration EC50: concentration required to inhibit luciferase activity in the replicon system by 50%.. ^d Selectivity index (ratio of CC ₅₀ to EC ₅₀ ).