SYNTHESIS OF 2',3'-DIDEOXY-D-ERYTHRO-HEX-2'-ENOPYRANOSYL NUCLEOSIDES FROM 5-AMINOURACILS AND 3,4,6-TRI-O-ACETYL-D-GLUCAL

Condensation of silylated N,N-disubstituted aminouracils (4) and 3,4,6-tri-O-acetyl-D-glucal (3) in the presence of TMS triflate as catalyst gave anomeric mixtures of 2',3'-dideoxy-D-erythro-hex-2'-enopyranosylnucleosides (5) and (6). The pure beta- and alpha-anomers were separated by chromatography and deprotected with a saturated solution of ammonia in methanol to give 1-(2',3'-dideoxy-beta-D-erythro-hex-2-enopyranosyl)-5-aminouracils (7) and their corresponding alpha-anomes (8), respectively. The anomeric configurations of these nucleosides were assigned by nmr analysis of the dihydro derivatives 9 and 10 obtained by hydrogenation of 7a and 8a, respectively. No significant activity against HIV-1 was found.