(3S,4aR,6aS,12aR,12bS)-3,11-diacetoxy-4,4,6a,12b-tetramethyl-1,3,4,4a,5,6,6a,12,12a,12b-decahydro-2H-benzo[a]xanthene 在
potassium tert-butylate 作用下,
以
四氢呋喃 、
叔丁醇 为溶剂,
反应 0.5h,
生成 (3S,4aR,6aS,12aR,12bS)-3-acetoxy-11-hydroxy-4,4,6a,12b-tetramethyl-1,3,4,4a,5,6,6a,12,12a,12b-decahydro-2H-benzo[a]xanthene