4-azido-3-O-benzyl-4,6-dideoxy-2-O-methyl-β-D-glucopyranosyl-(1->3)-2-O-benzoyl-4-O-benzyl-α-L-rhamnopyranosyl trichloroacetimidate 、 pent-4-enyl 4-O-benzyl-2-O-benzoyl-α-L-rhamnopyranosyl-(1->2)-3,4-di-O-benzyl-α-L-rhamnopyranosyl-(1->3)-4,6-di-O-benzyl-2-N-trichloroacetyl-β-D-galactosaminopyranoside 在
三氟甲磺酸三甲基硅酯 作用下,
以
二氯甲烷 为溶剂,
反应 1.5h,
以73%的产率得到pent-4-enyl 4-azido-3-O-benzyl-4,6-dideoxy-2-O-methyl-β-D-glucopyranosyl-(1->3)-2-O-benzoyl-4-O-benzyl-α-L-rhamnopyranosyl-(1->2)-3,4-di-O-benzyl-α-L-rhamnopyranosyl-(1->3)-4,6-di-O-benzyl-2-N-trichloroacetyl-α/β-D-galactosaminopyranoside