Reduction of virginiamycin S with sodium borohydride produces allo- and normal-dihydro-virginiamycin S. Reduction of the tosylhydrazone of virginiamycin S with sodium cyanoboro-hydride affords deoxyvirginiamycin S. These compounds are less active than virginiamycin S. Like virginiamycin S they enhance the activity of virginiamycin M1.
