N-苯基马来酰亚胺 、
methyl (1R,4S,5R,9S,10R,13S,14S)-14-ethenyl-14-hydroxy-5,9,13-trimethyltetracyclo[11.2.1.01,10.04,9]hexadecane-5-carboxylate 在
磷酸 作用下,
反应 24.0h,
以70%的产率得到methyl (1S,4S,5R,9S,10S,13S,17R,21S,22S)-5,9,13-trimethyl-18,20-dioxo-19-phenyl-19-azahexacyclo[11.9.1.01,10.04,9.014,22.017,21]tricos-14-ene-5-carboxylate