2,2-二甲氧基丙烷 、
(3R,4S,4aR,4bS,8aS)-4-Hydroxy-3-(1-hydroxy-ethyl)-4b,8,8-trimethyl-3,4,4a,4b,5,6,7,8,8a,9-decahydro-2-oxa-phenanthren-1-one 在
对甲苯磺酸 作用下,
生成 (4S,4aR,8aS,12aS,12bR,12cS)-2,2,4,9,9,12a-Hexamethyl-4a,8,8a,9,10,11,12,12a,12b,12c-decahydro-4H-1,3,5-trioxa-benzo[c]phenanthren-6-one 、 (4R,4aR,8aS,12aS,12bR,12cS)-2,2,4,9,9,12a-Hexamethyl-4a,8,8a,9,10,11,12,12a,12b,12c-decahydro-4H-1,3,5-trioxa-benzo[c]phenanthren-6-one