(+/-)-7-methoxy-2,8,10a-trimethyl-3-oxo-(10a
r)-1,2,3,9,10,10a-hexahydro-phenanthrene-2
t-carboxylic acid methyl ester 在
sodium hydroxide 作用下,
生成
(+/-)-7-methoxy-2,8,10a-trimethyl-3-oxo-(10ar)-1,2,3,9,10,10a-hexahydro-phenanthrene-2t-carboxylic acid