(8s,9r,10s,11s,13s,14s,16r,17r)-9-氟-17-(甲酰氧基)-11-羟基-10,13,16-三甲基-3-氧代-6,7,8,9,10,11,12,13,14,15,16,17-十二氢-3h-环戊[a]菲-17-羧酸