L(+)-rhamnose 、
allyl (3,4-di-O-benzyl-α-L-rhamnopyranosyl)-(1->3)-[2,3,4,6-tetra-O-benzyl-α-D-glucopyranosyl-(1->4)]-2-O-benzoyl-α-L-rhamnopyranoside 在
三氟甲磺酸三甲基硅酯 、 4 A molecular sieve 作用下,
以
乙醚 为溶剂,
以90%的产率得到allyl (2-O-acetyl-3,4-di-O-benzyl-α-L-rhamnopyranosyl)-(1->2)-(3,4-di-O-benzyl-α-L-rhamnopyranosyl)-(1->3)-[2,3,4,6-tetra-O-benzyl-α-D-glucopyranosyl-(1->4)]-2-O-benzoyl-α-L-rhamnopyranoside