Patent ID: 7816339

Claim:
A method for treating an infection by a virus which is a member of the Flaviviridae family of viruses, in a mammalian host, comprising administering to said host a therapeutically effective amount of a compound represented by structural formula IV or a pharmaceutically acceptable salt thereof or a pharmaceutical composition thereof which composition comprises a pharmaceutically acceptable carrier; wherein R 3 and R 4 are independently —OH or a pharmaceutically acceptable leaving group, wherein R 5 is —OH, a straight or branched chain C 9 to C 24 alkylphosphate or a straight or branched chain C 9 to C 24 alkenylphosphate group or a pharmaceutically acceptable leaving group and wherein R 1 and R 2 are independently C 1 to C 10 alkyl or wherein R 1 and R 2 taken together with N form a C 3 to C 7 ring represented by the following structural formula: wherein n and m are independently 0, 1, 2 or 3 and Q is CH 2 , NR, O, S, SO or SO 2 ; and R is independently H, C 1 to C 6 alkyl or C 1 to C 6 acyl or wherein R 1 and R 2 , taken together with the N, are represented by the structural formula: and wherein said pharmaceutically acceptable leaving groups are capable of being converted to —OH, -phosphate, —F or —CH 3 when the compound of structural formula IV is administered in vivo and are independently represented by structural formula wherein Y═H, CH 3 , CH 3 CH 2 —, CH 3 CH 2 CH 2 —, Me 2 CH—, Me 2 CH 2 CH 2 —, CH 3 CH 2 CH(Me)-, PhCH 2 —, HOOCCH 2 CH 2 —, HSCH 2 —, HOOCCH 2 —, MeSCH 2 CH 2 —, HOCH 2 —, H 2 N(CH 2 ) 4 —, or CH 3 CH(OH)—, or a pharmaceutically acceptable salt thereof, or Y, taken together with the alpha-carbon and N, form wherein the pharmaceutically acceptable leaving groups are capable of being converted to —OH, -phosphate, —F or —CH 3 when the compound of structural formula IV is administered in vivo and are independently represented by a structural formula selected from the group consisting of: in association with one or more further chemotherapeutic agents.