1β,2α,3α,24-tetrahydroxyolean-12-en-28-oic acid 以
吡啶 、
甲醇 、
乙醚 为溶剂,
生成 (4aS,6aS,6bR,8aR,9S,10S,11R,12S,12aR,12bS,14bS)-10,11,12-Triacetoxy-9-acetoxymethyl-2,2,6a,6b,9,12a-hexamethyl-1,3,4,5,6,6a,6b,7,8,8a,9,10,11,12,12a,12b,13,14b-octadecahydro-2H-picene-4a-carboxylic acid methyl ester