cumingianoside E 在
对甲苯磺酸 作用下,
以
二氯甲烷 为溶剂,
以26.8%的产率得到[(2R,3S,4S,5R,6R)-6-[[(3R,5R,7R,8R,9R,10S,14R,17S)-3-acetyloxy-17-[(2S,4R,5R)-4,5-dihydroxy-6-methylhept-6-en-2-yl]-4,4,8,10,14-pentamethyl-2,3,5,6,7,9,11,15,16,17-decahydro-1H-cyclopenta[a]phenanthren-7-yl]oxy]-3,4,5-trihydroxyoxan-2-yl]methyl acetate