(3aR,3a
1R,3bR,6aS,6bR,11bR)-methyl 3a-ethyl-9-methoxy-7-methyl-5-thioxo-3a,3a
1,3b,6a,6b,7,12,13-octahydro-1H-[1,3]dioxolo[4,5-a]indolizino[8,1-cd]carbazole-6a-carboxylate 在
碘甲烷 作用下,
生成
ent-3,4α-carbonyldioxy-16-methoxy-1-methyl-6,7-didehydro-aspidospermidine-3β-carboxylic acid methyl ester