丙酮 、 (22R,23R,24R)-22,23-dihydroxy-3α,5-cyclo-5α-ergostan-6-one 在
氢溴酸 作用下,
反应 0.17h,
以99%的产率得到(3S,5S,8S,9S,10R,13S,14S,17R)-3-Bromo-17-{(S)-1-[(4R,5R)-5-((R)-1,2-dimethyl-propyl)-2,2-dimethyl-[1,3]dioxolan-4-yl]-ethyl}-10,13-dimethyl-hexadecahydro-cyclopenta[a]phenanthren-6-one