氰化钾   、                                                                                      (1S,4aS,4bR,9R,10aS)-[9'α-(tert-butyldimethylsilyl)oxy]-1,2,3,4,4a,4b,5,6,7,9,10,10a-dodecahydro-1β-methoxycarbonyl-8-(2',2'-dimethoxyethyl)-1α,4aβ-dimethylphenanthren-7-one                                                                                                                                                              在
                                                                                                                                                                                 
18-冠醚-6   、                                                                                                  
二乙基氰化铝                                                                                                                                  作用下,
                                                                                                                以
                                                                                         
甲苯   、                                                                                         
苯                                                                                  为溶剂,
                                                                                                                                                    反应 20.0h,
                                                                                                                以75%的产率得到(4S,5S,7R,8R,9R,10S,16R)-7α-[(tert-butyldimethylsilyl)oxy]-8β-cyano-1,2,3,4,5,6,7,8,9,10,11,12,15,16-tetradecahydro-4β-methoxycarbonyl-16β-methoxy-17-oxa-cyclopenta[a]-4α,10β-dimethylphenanthrene