在
sodium methylate 作用下,
以
甲醇 、
二氯甲烷 为溶剂,
以89%的产率得到(2S,3R,4R,5R,6S)-2-[(2R,3S,4S,5R,6R)-5-[(2S,3R,4S,5R,6S)-3,4-dihydroxy-5-methoxy-6-methyloxan-2-yl]oxy-4-hydroxy-2-(hydroxymethyl)-6-[(1S,2S,4S,5'R,6R,7S,8R,9S,12S,13R,16S)-5',7,9,13-tetramethylspiro[5-oxapentacyclo[10.8.0.02,9.04,8.013,18]icos-18-ene-6,2'-oxane]-16-yl]oxyoxan-3-yl]oxy-6-methyloxane-3,4,5-triol