24-norchola-5,22-dien-3β-ol acetate 、
iso-butyronitrile oxide 生成 Acetic acid (3S,10R,13S,17R)-17-[(S)-1-(3-isopropyl-4,5-dihydro-isoxazol-5-yl)-ethyl]-10,13-dimethyl-2,3,4,7,8,9,10,11,12,13,14,15,16,17-tetradecahydro-1H-cyclopenta[a]phenanthren-3-yl ester