2-Azidomethyl-benzoic acid (3R,4S,5R,6R)-5-acetoxy-6-acetoxymethyl-4-benzoyloxy-2-(2,2,2-trifluoro-N-phenyl-acetimidoyloxy)-tetrahydro-pyran-3-yl ester 、
oleanolic acid 28-O-2,3,4,6-tetra-O-benzoyl-β-D-glucopyranosyl ester 在
4 A molecular sieve 、
叔丁基二甲硅基三氟甲磺酸酯 作用下,
以
二氯甲烷 为溶剂,
以91%的产率得到[(2S,3R,4S,5R,6R)-3,4,5-tribenzoyloxy-6-(benzoyloxymethyl)oxan-2-yl] (4aS,6aR,6aS,6bR,8aR,10S,12aR,14bS)-10-[(2R,3R,4S,5R,6R)-5-acetyloxy-6-(acetyloxymethyl)-3-[2-(azidomethyl)benzoyl]oxy-4-benzoyloxyoxan-2-yl]oxy-2,2,6a,6b,9,9,12a-heptamethyl-1,3,4,5,6,6a,7,8,8a,10,11,12,13,14b-tetradecahydropicene-4a-carboxylate