(3S,4S,4aR,5aR,6aR,7R,10aS,10bR)-4-Hydroxy-3,7,10a-trimethyl-3-vinyl-dodecahydro-5-oxa-cyclopropa[k]phenanthrene-7-carboxylic acid methyl ester 在
硫酸 作用下,
以
甲醇 、
水 为溶剂,
以83%的产率得到<1R-(1α,4aβ,4bα,7β,10aα)>-7-Ethenyl-1,2,3,4,4a,4b,5,6,7,8,10,10a-dodecahydro-1,4a,7-trimethyl-8-oxo-1-phenanthrencarbonsaeure-methylester