(6s,8s,10s,11s,13s,14s,16r,17s)-6,9-二氟-11-羟基-10,13,16-三甲基-3-氧代-17-(丙酰氧基)-6,7,8,9,10,11,12,13,14,15,16,17-十二氢-3h-环戊[a]菲-17-羧酸