5-chloro-2-ethyl-(4S)-hydroxypentanal lactol 、
8-methoxy-1,2,3,4,5,6-hexahydro-azepino[4,5-b]indole-5-carboxylic acid methyl ester 在
硼酸 、
三乙胺 作用下,
生成 (2R,3aR,10bR,12bR)-3a-Ethyl-2-hydroxy-8-methoxy-2,3,3a,4,6,11,12,12b-octahydro-1H-6,12a-diaza-indeno[7,1-cd]fluorene-5-carboxylic acid methyl ester 、
(-)-14β-hydroxyervinceine