、 5-(1-acetamido-2,3,4-tetra-O-acetyl-1-deoxy-D-ribotetritol-1-yl)-2-methyl-3-furoic acid 在
benzotriazol-1-yloxyl-tris-(pyrrolidino)-phosphonium hexafluorophosphate 、
N,N-二异丙基乙胺 作用下,
以
N,N-二甲基甲酰胺 为溶剂,
以89%的产率得到(2S)-2-{5-[(1-acetamido-2,3,4-tri-O-acetyl-1-deoxy-D-ribotetritol-1-yl)-2-methyl-3-furancarboxamido]-2-methoxycarbonyl}ethyl 2,3,4,6-tetra-O-acetyl-1-thio-β-D-galactopyranoside