(4S,10S)-17-Hydroxy-12-methoxy-4,10-dimethyl-2,3,4,5,6,7,10,15,16,17-decahydro-1H-cyclopenta[a]phenanthrene-4-carboxylic acid methyl ester                                                                                                                                                              在
                                                                                                                                                                                 
pyridinium chlorochromate                                                                                                                                  作用下,
                                                                                                                                                                                                                            以80%的产率得到methyl (4S,10S)-12-methoxy-4,10-dimethyl-17-oxo-1,2,3,5,6,7,15,16-octahydrocyclopenta[a]phenanthrene-4-carboxylate