(1R,3aS,3bS,5aR,7R,9aR,10aS,12aR)-1-{(1R)-3-[(2R)-3,3-Dimethyl-2-oxiranyl]-1-methylpropyl}-3a,6,6,12a-tetramethyltetradecahydro-1H-cyclopenta[a]cyclopropa[e]phenanthren-7-yl acetate (3beta, 24R)-24,25-epoxycycloartan-3-ol acetate AIDS-113950 AIDS113950