(1R,2S,3R,4R,5S)-2-Acetoxy-3-methoxy-8,8-dimethyl-4-phenylcarbamoyloxy-8-azonia-bicyclo[3.2.1]oct-6-ene 在
barium dihydroxide 、 Schwesinger-iminophosphoran-base 作用下,
生成 Acetic acid (1S,2R,5R,6R,7S)-6-acetoxy-2-dimethylamino-7-methoxy-5-methylamino-cyclohept-3-enyl ester