3β-acetoxy-21,22,23,24,25,26,27-heptanorlanost-8-en-20-oic acid                                                                                                                                                              在
                                                                                                                                                                                 sodium tetrahydroborate   、                                                                                                  
氯甲酸乙酯   、                                                                                                  
三乙胺                                                                                                                                  作用下,
                                                                                                                                                                                                                            生成                                                 Acetic acid (3S,5R,10S,13R,14R,17S)-17-hydroxymethyl-4,4,10,13,14-pentamethyl-2,3,4,5,6,7,10,11,12,13,14,15,16,17-tetradecahydro-1H-cyclopenta[a]phenanthren-3-yl ester