2,3,4,6-tetra-O-pivaloyl-α-D-galactopyranosyl bromide 、
tert-butyl (2S,5S)-5-{[(benzyloxy)carbonyl]amino}-2-{[(9H-fluoren-9-ylmethoxy)carbonyl]amino}-6-hydroxyhexanoate 在
silver silicate 、 4 A molecular sieve 作用下,
以
二氯甲烷 为溶剂,
反应 8.0h,
以60%的产率得到tert-butyl (2S,5S)-6-[[(3aR,5R,6S,7S,7aR)-2-tert-butyl-6,7-bis(2,2-dimethylpropanoyloxy)-5-(2,2-dimethylpropanoyloxymethyl)-5,6,7,7a-tetrahydro-3aH-[1,3]dioxolo[4,5-b]pyran-2-yl]oxy]-2-(9H-fluoren-9-ylmethoxycarbonylamino)-5-(phenylmethoxycarbonylamino)hexanoate