Compounds and pharmaceutical compositions active against HIV are provided, as is a method for the treatment of HIV infection in humans and other host animals is provided comprising administering an effective amount of a &bgr;-L-(2′ or 3′-azido)-2′,3′-dideoxy-5-fluorocytosine of the formula wherein R is H, acyl, monophosphate, diphosphate, or triphosphate, or a stabilized phosphate derivative (to form a stabilized nucleotide prodrug), and R′ is H, acyl, or alkyl.