2,4-di-O-benzoyl-3-O-bromoacetyl-α-L-rhamnopyranosyl chloride 、
methyl O-<3,4,6-tri-O-benzyl-α-D-galactopyranosyl>-(1<*>3)-O-(2-acetamido-4,6-O-benzylidene-2-deoxy-α-D-glucopyranosyl)-(1<*>3)-2,4-di-O-benzyl-α-L-rhamnopyranoside 在
2,6-二叔丁基-4-甲基吡啶 、 4 A molecular sieve 、
silver trifluoromethanesulfonate 作用下,
以
二氯甲烷 为溶剂,
反应 4.0h,
以94%的产率得到methyl O-(2,4-di-O-benzoyl-3-O-bromoacetyl-α-L-rhamnopyranosyl)-(1<*>2)-O-(3,4,6-tri-O-benzyl-α-L-D-galactopyranosyl)-(1<*>3)-O-(2-acetamido-4,6-benzylidene-2-deoxy-α-D-glucopyranosyl)-(1<*>3)-2,4-di-O-benzyl-α-L-rhamnopyranoside