6α-fluoro-17α-hydroxy-16α-methylandrosta-4,9(11)-dien-3-one 17β-carboxylic acid 17-butyrate   、                                                                                      butyric anhydride, 6α-fluoro-17α-hydroxy-16α-methylandrosta4,9(11)-dien-3-one 17β-carboxylic acid 17-butyrate                                                                                                                                                                                                                                                                                                          生成                                                 6α-Fluoro-17α-hydroxy-16α-methylandrosta-4,9(11)-dien-3-one 17β-carboxylic acid methyl ester 17-butyrate