benzyl 2,4,6-tri-O-acetyl-3-O-trityl-β-D-galactopyranoside 、 3,4-di-O-acetyl-1,2-O-[1-(exo-,endo-cyano)ethylidene]-6-O-tosyl-α-D-galactopyranose 在
triphenylmethyl perchlorate 作用下,
以
二氯甲烷 为溶剂,
以28%的产率得到benzyl 2,3,4-tri-O-acetyl-6-O-tosyl-β-D-galactopyranosyl-(1->3)-2,4,6-tri-O-acetyl-β-D-galactopyranoside