14-hydroxywithanolide D 、
2-巯基乙醇 在
盐酸 作用下,
以
乙醇 为溶剂,
以50%的产率得到(1S,2R,6S,7R,12S,14R,15R,18S,19R)-18-[(1R)-1-[(2R)-4,5-dimethyl-6-oxo-2,3-dihydropyran-2-yl]-1-hydroxyethyl]-6,15-dihydroxy-2,19-dimethyl-8-oxa-11-thiapentacyclo[12.7.0.02,7.07,12.015,19]henicos-4-en-3-one