4′-or nucleosides for the treatment of HCV

1. A compound according to Formula 1001:

or a pharmaceutically acceptable salt thereof, wherein:

Base is a natural or unnatural pyrimidine nucleobase;

PD is

W is S or O; one of X and Y is an N-linked amino acid or an N-linked amino alcohol, and the other of X and Y is OR 1 ;

each of Z 1 , Z 2 , Z 3 , and Z 4 is independently H, —OH, —OCH 3 , —N 3 , —CH 3 , —Cl, or —F, such that if one of Z 1 and Z 2 is —OH, then the other of Z 1 and Z 2 cannot be —OH, and such that if one of Z 3 and Z 4 is —OH, then the other of Z 3 and Z 4 cannot be —OH;

each R 1 is independently alkyl, cycloalkyl, aryl, heteroaryl, arylalkyl, heteroarylalkyl, alkylcarbonylthioalkyl, alkoxycarbonylalkyl, arylalkoxycarbonylalkyl, alkylcarbonylalkoxy(arylalkyl), cycloalkylcarbonylalkoxyl, alkoxycarbonylaminoalkylcarbonylthioalkyl, hydroxylalkylcarbonylthioalkyl, or aminoalkylcarbonylalkoxycarbonylthioalkyl; and

R is alkyl or alkynyl;

wherein each and any heteroaryl group is independently selected from furanyl, imidazolyl, isothiazolyl, isoxazolyl, oxadiazolyl, oxadiazolyl, oxazolyl, pyrazinyl, pyrazolyl, pyridazinyl, pyridyl, pyrimidinyl, pyrrolyl, thiadiazolyl, thiazolyl, thienyl, tetrazolyl, triazinyl, triazolyl, benzofuranyl, benzimidazolyl, benzoisoxazolyl, benzopyranyl, benzothiadiazolyl, benzothiazolyl, benzothienyl, benzotriazolyl, benzoxazolyl, furopyridyl, imidazopyridinyl, imidazothiazolyl, indolizinyl, indolyl, indazolyl, isobenzofuranyl, isobenzothienyl, isoindolyl, isoquinolinyl, isothiazolyl, naphthyridinyl, oxazolopyridinyl, phthalazinyl, pteridinyl, purinyl, pyridopyridyl, pyrrolopyridyl, quinolinyl, quinoxalinyl, quinazolinyl, thiadiazolopyrimidyl, thienopyridyl, acridinyl, benzindolyl, carbazolyl, dibenzofuranyl, perimidinyl, phenanthrolinyl, phenanthridinyl, phenarsazinyl, phenazinyl, phenothiazinyl, phenoxazinyl, or xanthenyl.

2. The compound of claim 1 , or a pharmaceutically acceptable salt thereof, wherein the nucleobase is selected from 1-pyrimidinyl, 9-adeninyl, 2-mercapto-1-pyrimidinyl, 4-mercapto-1-pyrimidinyl, 1-uracilyl, 5-halo-1-uracilyl, 5-fluoro-1-uracilyl, 5-aza-1-cytosinyl, and 5-aza-1-uracilyl;

each R 1 is independently alkyl, cycloalkyl, aryl, heteroaryl, aryl-alkyl, heteroaryl-alkyl, alkyl-carbonyl-thioalkyl, alkoxy-carbonyl-alkyl, aryl-alkoxy-carbonyl-alkyl, alkyl-carbonyl-alkoxy-(arylalkyl), cycloalkyl-carbonyl-alkoxyl, alkoxycarbonyl-amino-alkyl-carbonyl-thio-alkyl, hydroxyl-alkyl-carbonyl-thioalkyl, or amino-alkyl-carbonyl-alkoxy-carbonyl-thio-alkyl;

each alkyl is independently straight or branched C 1-10 alkyl, unsubstituted or substituted with one or more halogen, fluoro, chloro, bromo, iodo, hydroxyl, C 3-15 cycloalkyl, phenyl C 1-10 alkyl, biphenyl C 1-10 alkyl, naphthyl C 1-10 alkyl, amino, C 1-10 alkyl-amino, phenyl-amino, biphenyl-amino, naphthyl-amino, C 1-10 alkoxy, phenyloxy, biphenyloxy, naphthyloxy, nitro, cyano, sulfonic acid, sulfate, phosphonic acid, or phosphate;

each cycloalkyl is independently a C 3-15 cycloalkyl, unsubstituted or substituted with one or more halogen, fluoro, chloro, bromo, iodo, hydroxyl, carbonyl, amino, C 1-10 alkylamino, phenyl-amino, biphenyl-amino, naphthyl-amino, C 1-10 alkoxy, phenyloxy, biphenyloxy, naphthyloxy, nitro, cyano, sulfonic acid, sulfate, phosphonic acid, or phosphate;

each aryl is independently phenyl, biphenyl, or naphthyl, unsubstituted or substituted with one or more halogen, fluoro, chloro, bromo, iodo, C 1-10 alkyl, halo C 1-10 alkyl, hydroxyl, amino, C 1-10 alkyl-amino, phenyl-amino, biphenyl-amino, naphthyl-amino, C 1-10 alkoxy, phenyloxy, biphenyloxy, naphthyloxy, nitro, cyano, sulfonic acid, sulfate, phosphonic acid, or phosphate;

wherein each and any heteroaryl is independently selected from furanyl, imidazolyl, isothiazolyl, isoxazolyl, oxadiazolyl, oxadiazolyl, oxazolyl, pyrazinyl, pyrazolyl, pyridazinyl, pyridyl, pyrimidinyl, pyrrolyl, thiadiazolyl, thiazolyl, thienyl, tetrazolyl, triazinyl, triazolyl, benzofuranyl, benzimidazolyl, benzoisoxazolyl, benzopyranyl, benzothiadiazolyl, benzothiazolyl, benzothienyl, benzotriazolyl, benzoxazolyl, furopyridyl, imidazopyridinyl, imidazothiazolyl, indolizinyl, indolyl, indazolyl, isobenzofuranyl, isobenzothienyl, isoindolyl, isoquinolinyl, isothiazolyl, naphthyridinyl, oxazolopyridinyl, phthalazinyl, pteridinyl, purinyl, pyridopyridyl, pyrrolopyridyl, quinolinyl, quinoxalinyl, quinazolinyl, thiadiazolopyrimidyl, thienopyridyl, acridinyl, benzindolyl, carbazolyl, dibenzofuranyl, perimidinyl, phenanthrolinyl, phenanthridinyl, phenarsazinyl, phenazinyl, phenothiazinyl, phenoxazinyl, and xanthenyl;

each arylalkyl is independently aryl C 1-10 alkyl; wherein aryl is defined above;

each heteroarylalkyl is independently heteroaryl C 1-10 alkyl; wherein heteroaryl is defined above;

each alkoxy is independently —OR′ wherein R′ is alkyl or cycloalkyl and wherein alkyl is C 1-10 alkyl and cycloalkyl is C 3-15 cycloalkyl; and

each alkynyl is independently straight or branched C 2-11 alkynyl, unsubstituted or substituted with one or more halogen, fluoro, chloro, bromo, iodo, hydroxyl, amino, C 1-10 alkylamino, phenylamino, biphenylamino, naphthylamino, C 1-10 alkoxy, phenyloxy, biphenyloxy, naphthyloxy, nitro, cyano, sulfonic acid, sulfate, phosphonic acid, or phosphate.

3. The compound of claim 1 , or a pharmaceutically acceptable salt thereof, wherein Z 1 is —H, Z 2 is —OH or —H, Z 3 is —H, and Z 4 is —OH or —F.

4. The compound of claim 1 , or a pharmaceutically acceptable salt thereof, wherein Z 1 is —H, Z 2 is —H, Z 3 is —H, and Z 4 is —F.

5. The compound of claim 1 , or a pharmaceutically acceptable salt thereof, wherein Z 1 is —H, Z 2 is —F, Z 3 is —H, and Z 4 is —OH.

6. The compound of claim 1 , or a pharmaceutically acceptable salt thereof, wherein Z 1 is —H, V is —OH, Z 3 is —H, and Z 4 is —F, or —N 3 .

7. The compound of claim 1 , or a pharmaceutically acceptable salt thereof, wherein Z 1 is —H, Z 2 is —OH, and Z 3 and Z 4 are each —H.

8. The compound of claim 1 , or a pharmaceutically acceptable salt thereof, wherein Z 3 is —H, and each of Z 1 , Z 2 , and Z 4 is independently —H, —OH, —N 3 , —CH 3 , —Cl, or —F, such that if one of Z 1 and Z 2 is —OH, then the other of Z 1 and Z 2 cannot be —OH.

9. The compound of claim 1 , or a pharmaceutically acceptable salt thereof, wherein R is methyl, ethyl, isopropyl, ethynyl or propargyl.

10. The compound of claim 1 , or a pharmaceutically acceptable salt thereof, wherein

PD is W is S or O; one of X and Y is an N-linked amino acid or an N-linked amino alcohol; and the other of X and Y is —OR 1 ;

each of Z 1 , Z 2 , Z 3 , and Z 4 is independently —H, —OH, —N 3 , —CH 3 , —Cl, or —F, such that if one of Z 1 and Z 2 is —OH, then the other of Z 1 and Z 2 cannot be —OH—, and such that if one of Z 3 and Z 4 is —OH, then the other of Z 3 and Z 4 cannot be —OH—;

each R 1 is independently alkyl, cycloalkyl, aryl, heteroaryl, arylalkyl, heteroarylalkyl, alkylcarbonylthioalkyl, alkoxycarbonylalkyl, arylalkoxycarbonylalkyl, alkylcarbonylalkoxy(arylalkyl), cycloalkylcarbonylalkoxyl, alkoxycarbonylaminoalkylcarbonylthioalkyl, hydroxylalkylcarbonylthioalkyl, or aminoalkylcarbonylalkoxycarbonylthioalkyl.

11. The compound of claim 1 according to Formula III:

or a pharmaceutically acceptable salt thereof;

wherein

R 3 is alkyl, alkoxyl, hydroxylalkyl, acylalkyl, or alkoxylcarbonylalkyl.

12. The compound of claim 1 , selected from the group consisting of the following formulae:

or a pharmaceutically acceptable salt thereof, wherein R 9 is methyl or hydroxymethyl.

13. The compound of claim 1 , selected from the group consisting of the following formulae:

or pharmaceutically acceptable salt thereof; wherein R 10 is alkyl, hydroxylalkyl, acylalkyl, or alkoxylcarbonylalkyl, and Ar is an aryl group.

14. The compound of claim 1 , selected from the following:

or a pharmaceutically acceptable salt thereof.

15. A pharmaceutical composition comprising: (i) a compound of claim 1 , or a pharmaceutically acceptable salt thereof, and (ii) a pharmaceutically acceptable excipient, carrier or diluent.

16. A method for the treatment of hepatitis C virus in a host in need thereof, wherein said method comprises administering to said host an effective treatment amount of a compound of claim 1 , or a pharmaceutically acceptable salt thereof.

17. The method of any claim 16 , further comprising administering to said host a second anti-viral agent, wherein said second anti-viral agent is selected from an interferon, a nucleotide analogue, a polymerase inhibitor, an NS3 protease inhibitor, an NS5A inhibitor, an entry inhibitor, a non-nucleoside polymerase inhibitor, a cyclosporine immune inhibitor, an NS4A antagonist, an NS4B-RNA binding inhibitor, a locked nucleic acid mRNA inhibitor, and a cyclophilin inhibitor.