3α,3β-mercapto-11-oxo-18β-olean-1,12-dien-29-oic acid 、
methyl (1-O-(2-iodoethyl)-2,3,4-tri-O-acetyl-1-thio-β-D-glucopyranosyl)uronate 在
potassium carbonate 作用下,
以
水 、
丙酮 为溶剂,
生成 (3α,18β,20β)-3-{2-[methyl (2,3,4-tri-O-acetyl-1-thio-β-D-glucopyranosyl)uronate]ethylthio}-11-oxo-olean-2,12-dien-29-oic acid 、 (3β,18β,20β)-3-{2-[methyl (2,3,4-tri-O-acetyl-1-thio-β-D-glucopyranosyl)uronate]ethylthio}-11-oxo-olean-2,12-dien-29-oic acid