acetic acid 4-acetoxy-2-acetoxymethyl-5-benzyloxycarbonylamino-6-(2,2,2-trichloroacetimidoyloxy)-tetrahydro-pyran-3-yl ester   、                                                                                      
豆甾醇                                                                                                                                                              在
                                                                                                                                         
三氟化硼乙醚                                                                                                                                                                          作用下,
                                                                                                                以
                                                                                         
甲醚                                                                                  为溶剂,
                                                                                                                                                    反应 16.0h,
                                                                                                                以21%的产率得到acetic acid 4-acetoxy-2-acetoxymethyl-5-benzyloxycarbonylamino-6-[17-(4-ethyl-1,5-dimethyl-2-hexenyl)-10,13-dimethyl-2,3,4,7,8,9,10,11,12,13,14,15,16,17-tetradecahydro-1H-cydopenta[a]phenanthren-3-yloxy]-tetrahydro-pyran-3-yl ester