Trichloro-acetic acid (3S,8R,9S,10R,13S,14S,16R,17S)-17-acetyl-10,13-dimethyl-2,3,4,7,8,9,10,11,12,13,14,15,16,17-tetradecahydro-1H-20-oxa-cyclopropa[16,17]cyclopenta[a]phenanthren-3-yl ester 在
sodium iodide 作用下,
以
丙酮 为溶剂,
生成
16β-Brom-21-iod-3β-trichloracetoxy-17α-hydroxy-pregn-5-en-20-on