(4R,5R,6S)-6-((R)-2,2-Dimethyl-[1,3]dioxolan-4-yl)-4,5-dihydroxy-5,6-dihydro-4H-pyran-2-carboxylic acid methyl ester 、
(2R,3S,4S,5S,6R)-4,5-Diacetoxy-2-chloro-6-((R)-1,2-diacetoxy-ethyl)-3-phenylsulfanyl-tetrahydro-pyran-2-carboxylic acid methyl ester 在
disodium hydrogenphosphate 、 4 A molecular sieve 、
silver trifluoromethanesulfonate 作用下,
以
1,2-二氯乙烷 、
甲苯 为溶剂,
以31%的产率得到(4R,5R,6S)-4-[(2S,3S,4S,5S,6R)-4,5-Diacetoxy-6-((R)-1,2-diacetoxy-ethyl)-2-methoxycarbonyl-3-phenylsulfanyl-tetrahydro-pyran-2-yloxy]-6-((R)-2,2-dimethyl-[1,3]dioxolan-4-yl)-5-hydroxy-5,6-dihydro-4H-pyran-2-carboxylic acid methyl ester