(2R,3R,4R,5R,6S)-3,5-Bis-benzyloxy-2-methoxy-6-methyl-tetrahydro-pyran-4-ol 、
Chloro-acetic acid (2S,3S,4R,5R,6S)-4,5-bis-benzyloxy-6-ethylsulfanyl-2-methyl-tetrahydro-pyran-3-yl ester 在
molecular sieve 、 iodonium di(2,4,6-trimethylpyridine) perchlorate 作用下,
以
乙醚 、
1,2-二氯乙烷 为溶剂,
以84%的产率得到Chloro-acetic acid (2S,3S,4R,5R,6S)-4,5-bis-benzyloxy-6-((2R,3R,4R,5S,6S)-3,5-bis-benzyloxy-2-methoxy-6-methyl-tetrahydro-pyran-4-yloxy)-2-methyl-tetrahydro-pyran-3-yl ester