O-(2,3,4-tri-O-acetyl-6-O-benzyl-β-D-galactopyranosyl)-(1->4)-3-O-acetyl-6-O-benzoyl-2-deoxy-2-dimethylmaleimido-β-D-glucopyranosyl trichloroacetimidate 、 O-(3,4,6-tri-O-benzyl)-α-D-mannopyranosyl)-(1->3)-(2-O-benzoyl-4,6-O-benzylidene-β-D-mannopyranosyl)-(1->4)-(3,6-di-O-benzyl-2-deoxy-2-dimethylmaleimido-β-D-glucopyranosyl)-(1->4)-3,6-di-O-benzyl-2-deoxy-2-dimethylmaleimido-β-D-glucopyranosyl azide 在
三氟甲磺酸三甲基硅酯 、 4 A molecular sieve 作用下,
以
二氯甲烷 为溶剂,
以75%的产率得到[(2R,3S,4R,5R,6S)-6-[(2R,3S,4S,5R,6R)-2-[[(2R,4aR,6S,7S,8S,8aR)-6-[(2R,3S,4R,5R,6S)-6-[(2R,3S,4R,5R,6R)-6-azido-5-(3,4-dimethyl-2,5-dioxopyrrol-1-yl)-4-phenylmethoxy-2-(phenylmethoxymethyl)oxan-3-yl]oxy-5-(3,4-dimethyl-2,5-dioxopyrrol-1-yl)-4-phenylmethoxy-2-(phenylmethoxymethyl)oxan-3-yl]oxy-7-benzoyloxy-2-phenyl-4,4a,6,7,8,8a-hexahydropyrano[3,2-d][1,3]dioxin-8-yl]oxy]-4,5-bis(phenylmethoxy)-6-(phenylmethoxymethyl)oxan-3-yl]oxy-4-acetyloxy-5-(3,4-dimethyl-2,5-dioxopyrrol-1-yl)-3-[(2S,3R,4S,5S,6R)-3,4,5-triacetyloxy-6-(phenylmethoxymethyl)oxan-2-yl]oxyoxan-2-yl]methyl benzoate