乙酸酐 、
(4aR,4bR,8S,10aR,10bS,12aS)-8-Hydroxy-10a,12a-dimethyl-4a,7,8,9,10,10a,10b,11,12,12a-decahydro-4bH-1-oxa-chrysene-2,5-dione 在
吡啶 、
4-二甲氨基吡啶 作用下,
反应 16.0h,
以4 mg的产率得到Acetic acid (4aR,4bR,8S,10aR,10bS,12aS)-10a,12a-dimethyl-2,5-dioxo-4a,4b,5,7,8,9,10,10a,10b,11,12,12a-dodecahydro-2H-1-oxa-chrysen-8-yl ester