Patent ID: 8637475

Claim:
A compound of the Formula (XIII): or a pharmaceutically acceptable salt thereof, wherein: R 3 is selected from the group consisting of H; mono-, di-, and tri-phosphate or a stabilized phosphate prodrug; acyl; a sulfonate ester; optionally substituted alkyl sulfonyl; optionally substituted arylsulfonyl; a lipid; an amino acid; a carbohydrate; a peptide; cholesterol; and a pharmaceutically acceptable leaving group which when administered in vivo is capable of providing a compound wherein R 3 is independently H, or mono-, di- or triphosphate; B is an optionally substituted 3-7 membered heterocyclic ring consisting of C, O and/or S atoms; Base is selected from the group consisting of: wherein each R′, R″, R′″ and R″″ are independently selected from the group consisting of H, OH, substituted or unsubstituted alkyl, substituted or unsubstituted alkenyl, substituted or unsubstituted alkynyl, cycloalkyl, Br-vinyl, —O-alkyl, O-alkenyl, O-alkynyl, O-aryl, O-aralkyl, —O-acyl, O-cycloalkyl, NH 2 , NH-alkyl, N-dialkyl, NH-acyl, N-aryl, N-aralkyl, NH-cycloalkyl, SH, S-alkyl, S-acyl, S-aryl, S-cycloalkyl, S-aralkyl, F, Cl, Br, I, CN, COOH, CONH 2 , CO 2 -alkyl, CONH-alkyl, CON-dialkyl, OH, CF 3 , CH 2 OH, (CH 2 ) m OH, (CH 2 ) m NH 2 , (CH 2 ) m COOH, (CH 2 ) m CN, (CH 2 ) m NO 2 and (CH 2 ) m CONH 2 ; m is 0 or 1; W is C—R″ or N; T and V independently are CH or N; Q is CH, —CCl, —CBr, —CF, —CI, —CCN, —C—COOH, —C—CONH 2 , or N; Q 1 and Q 2 independently are N or C—R; R is H, alkyl, or acyl; and Q 3 , Q 4 , Q 5 and Q 6 independently are N or CH.