The present invention relates to 1,3-benzodiazepin-2-ones and 1,3-benzoxazepin-2-ones of formula I: ##STR1##

or stereoisomeric forms, stereoisomeric mixtures, or pharmaceutically acceptable salt forms thereof, which are useful as inhibitors of HIV reverse transcriptase, and to pharmaceutical compositions and diagnostic kits comprising the same, and methods of using the same for treating viral infection or as an assay standard or reagent.