Synthesis and Antiviral Activity of Fluoro-substituted Apio Dideoxyuncleoside

Novel fluoro-substituted apio dideoxyuncleoside(($\pm$)-3a and ($\pm$)-3b) were efficiently synthesized stalling from 1,3-dihydroxyacetone via Horner-Emmons olefination as a key step. Cyclization of fluoro ester ($\pm$)-6 under acidic conditions to the fluorolactone was smoothly proceeded in favor of trans-fluorolactone due to the favorable transition state with equatorial hydroxymethyl substituent. Unfortunately the final nucleosides($\pm$) -3a and ($\pm$)-3b were found to be inactive against several viruses such as HIV-1, HSV- I , HSV-2 and HCMV.