A number of 3'-fluoro-3'-deoxythymidine 5'-phosphonates and nucleoside
5'-phosphorofluoridates were prepared to study their ability to inhib
it replication of HIV-1. Compounds, the 5'-phosphorofluoridates of 3'-
azido-3'-deoxythymidine (VIIIc), 3'-fluoro-3'-deoxythymidine (VIIId) a
nd 3'-deoxy-2',3'-didehydrothymidine (VIIIe), exhibit potent anti-HTV-
1 activities.