3′-or 2′-hydroxymethyl substituted nucleoside derivatives for treatment of hepatitis virus infections

1. A method for the treatment of hepatitis C virus (HCV) infection comprising administering to a host in need thereof an anti-HCV effective amount of a compound selected from the group consisting of formulas [I]–[IV] below and mixtures of two or more thereof:

wherein:

R is selected from the group consisting of:

or a pharmaceutically acceptable salt or prodrug thereof, optionally in combination with a pharmaceutically acceptable carrier.

2. The method of claim 1 , further comprising administering the compound in combination or alternation with one or more additional anti-HCV agents.

3. The method of claim 2 , wherein the additional HCV agent is selected from the group consisting of interferon, macrokine, heptazyme, ribavarin, amantadine, ofloxacin, zadaxin and reticulose.

4. A method for the treatment of hepatitis D virus (HDV) infection comprising administering to a host in need thereof an anti-HDV effective amount of a compound selected from the group consisting of formulas [I]–[IV] below and mixtures of two or more thereof:

wherein:

R is selected from the group consisting of:

or a pharmaceutically acceptable salt or prodrug thereof, optionally in combination with a pharmaceutically acceptable carrier.

5. The method of claim 4 , further comprising administering the compound in combination or alternation with one or more additional anti-HDV agents.

6. The method of claim 5 , wherein the additional HDV agent is selected from the group consisting of FTC, L-FMAU, interferon, beta-D-dioxolanyl-guanine (DXG), beta-D-dioxolanyl-2,6-diaminopurine (DAPD), beta-D-dioxolanyl-6-chloropurine (ACP), beta-D-dioxolanyl-2-aminopurine (ADP), famciclovir, penciclovir, bis-POM PMEA (adefovir dipivoxil); lobucavir, ganciclovir, ribavarin, lamivudine (3TC), L-thymidine (L-dT), L-2′-deoxycytidine (L-dT), L-2′-deoxycytidine-3′, 5′-diO-valyl (D or L), entecavir (BMS-200475), adefovir, L-D4FC, D-D4FC, and mycophenolic acid (an IMPDH inhibitor).

7. A pharmaceutical composition for the treatment of HCV comprising an anti-HCV agent and an anti-HCV effective amount of a compound selected from the group consisting of formulas [I]–[IV] below and mixtures of two or more thereof:

wherein:

R is independently selected from the group consisting of:

or a pharmaceutically acceptable salt or prodrug thereof, optionally in combination with a pharmaceutically acceptable carrier.

8. A pharmaceutical composition for the treatment of HDV comprising an anti-HDV agent and an anti-HDV effective amount of a compound selected from the group consisting of formulas [I]–[IV] below and mixtures of two or more thereof:

wherein:

R is independently selected from the group consisting of:

or a pharmaceutically acceptable salt or prodrug thereof, optionally in combination with a pharmaceutically acceptable carrier.

9. A process for stereospecifically preparing a 5′-modified pyrimidine β-nucleoside comprising:

a. applying the Mitsunobu reaction to a chiral compound of the formula;

b. selectively protecting the 3′β-position of the resulting nucleoside of step (a) with a benzoyl protecting group or an acid labile protecting group;

c. subjecting the resulting 3′β-protected anhydro derivative of step (b) to mild alkaline hydrolysis, followed by phosphorylating the ring-opened, 3′β-protected product with a phosphorylating agent;

d. Saponifiction of the benzoyl group of the resulting product of step (c) to give the desired β-nucleoside 5′-phosphate; and

e. Optionally oxidizing the 5′-phosphate to obtain the 5′-phosphite.

10. The process of claim 9 , wherein the acid labile agent is selected from the group consisting of tetrahydropyranyl (THP), a trityl group, or dimethyl-t-butylsilyl (DBMS).

11. The method of claim 1 , wherein the compound is Formula I.

12. The method of claim 1 , wherein the compound is Formula II.

13. The method of claim 1 , wherein the compound is Formula III.

14. The method of claim 1 , wherein the compound is Formula IV.

15. The method of claim 11 , wherein R is H.

16. The method of claim 12 , wherein R is H.

17. The method of claim 13 , wherein R is H.

18. The method of claim 14 , wherein R is H.

19. The method of claim 4 , wherein the compound is Formula I.

20. The method of claim 4 , wherein the compound is Formula II.

21. The method of claim 4 , wherein the compound is Formula III.

22. The method of claim 4 , wherein the compound is Formula IV.

23. The method of claim 19 , wherein R is H.

24. The method of claim 20 , wherein R is H.

25. The method of claim 21 , wherein R is H.

26. The method of claim 22 , wherein R is H.

27. The pharmaceutical composition of claim 7 , wherein the compound is Formula I.

28. The pharmaceutical composition of claim 7 , wherein the compound is Formula II.

29. The pharmaceutical composition of claim 7 , wherein the compound is Formula III.

30. The pharmaceutical composition of claim 7 , wherein the compound is Formula IV.

31. The pharmaceutical composition of claim 27 , wherein R is H.

32. The pharmaceutical composition of claim 28 , wherein R is H.

33. The pharmaceutical composition of claim 29 , wherein R is H.

34. The pharmaceutical composition of claim 30 , wherein R is H.

35. The pharmaceutical composition of claim 8 , wherein the compound is Formula I.

36. The pharmaceutical composition of claim 8 , wherein the compound is Formula II.

37. The pharmaceutical composition of claim 8 , wherein the compound is Formula III.

38. The pharmaceutical composition of claim 8 , wherein the compound is Formula IV.

39. The pharmaceutical composition of claim 35 , wherein R is H.

40. The pharmaceutical composition of claim 36 , wherein R is H.

41. The pharmaceutical composition of claim 37 , wherein R is H.

42. The pharmaceutical composition of claim 38 , wherein R is H.