Design and Synthesis of Apio Nucleosides with Exocyclic Methylene Substituent

Apio nucleosides belong to unique classes of nucleosides in that 4'-hydroxymethyl group moves to 3'-position. Among thse compounds. we found that apio dideoxyadenosine (apio-ddA) exhibited potent antiviral activity and apio-d4A showed potent anti-HCMV activity. Based on thse findings. it was of great interest to design and synthesize Anio nucleoside anlogues with various substituents such as fluorn or azido group. In order to synthesize apio analogues. the glyxosyl dondr. D-. and L-apio sugar acetates were first synthesized. starting from D-gallas. condensed whth silylated N4-benzoylcytosine. and then convenged to the linal D-andL-nucleosides. Synthesist of the D-and-apio nucieosides will be prssented in detail aht th the meeting.