9H-fluoren-9-ylmethyl [(2R,3S,4R,5R,6S)-3-hydroxy-2-(hydroxymethyl)-6-prop-2-enoxy-5-(2,2,2-trichloroethoxycarbonylamino)oxan-4-yl] carbonate 、
methyl 5-acetamido-4,7,8,9-tetra-O-acetyl-3,5-dideoxy-D-glycero-D-galacto-2-nonulopyranosonate 2-(N-phenyl)trifluoroacetimidate 在
三氟甲磺酸三甲基硅酯 作用下,
以
丙腈 为溶剂,
反应 6.0h,
以95%的产率得到methyl (2R,4S,5R,6R)-5-acetamido-4-acetyloxy-2-[[(2R,3S,4R,5R,6S)-4-(9H-fluoren-9-ylmethoxycarbonyloxy)-3-hydroxy-6-prop-2-enoxy-5-(2,2,2-trichloroethoxycarbonylamino)oxan-2-yl]methoxy]-6-[(1S,2R)-1,2,3-triacetyloxypropyl]oxane-2-carboxylate