SYNTHESIS, STRUCTURAL STUDIES AND ANTIRETROVIRAL EVALUATION OF 3'-AZA-4'-THIA-2',3'-DIDEOXYNUCLEOSIDES (THIAZOLIDINE-NUCLEOSIDE ANALOGS)

Starting with the concept that heterocyclic pseudo-ribose rings could confer potent antiviral activity to nucleoside analogues, we synthesiz ed 3'-aza-4'-thia-2',3'-dideoxynucleosides. The synthesis of such anal ogues required the preparation of N-protected-1,3-thiazolidines adequa tely disubstituted in 2- and 5-positions. Introduction of nucleobases on these sugar-like thiazolidines was achieved through coupling reacti ons using tin(IV) chloride as a catalyst. The N-protecting group (N-fl uorenylmethoxycarbonyl, N-acetyl and N-tosyl) of the thiazolidine ring is crucial for final deprotection of 3'-aza-4'-thia-2',3'-dideoxynucl eosides. None of these compounds were found active on HIV-infected MT- 4 cells.