16,17-Oxido-5-pregnen-3.beta.-ol-20-one-3-acetate 16.alpha.,17.alpha.-Epoxypregnenolone acetate 3.beta.-Acetoxy-16.alpha.,17.alpha.-epoxypregn-5-en-20-one 34209-81-9 NSC21455 Pregn-5-en-20-one, 16.alpha.,17-epoxy-3.beta.-hydroxy-, acetate Pregn-5-en-20-one, 3-(acetyloxy)-16,17-epoxy-, (3.beta.,16.alpha.)-