A synthetic approach to polysialogangliosides containing α-sialyl-(2 → 8)-sialic acid: total synthesis of ganglioside GD3
作者:Hideki Ishida、Yasuhiro Ohta、Yoji Tsukada、Makoto Kiso、Akira Hasegawa
DOI:10.1016/0008-6215(93)84025-2
日期:1993.8
phenylthio. Compound 8 was converted into the methyl beta-thioglycoside via O-benzoylation, replacement of the 2-(trimethylsilyl)ethyl group by acetyl, and introduction of the methylthio group by reaction with methylthiotrimethylsilane. Compound 17 was converted, via O-acetylation, selective removal of the 2-(trimethylsilyl)ethyl group, and reaction with trichloroacetonitrile, into the alpha-trichloroacetimidate
描述了神经节苷脂GD3的立体控制的,容易的全合成,该方法是拟议的系统方法的一个实例,该方法用于制备神经节苷脂,该神经节苷脂包含一个α-唾液酸-(2-> 8)-唾液酸单元,其α-糖基与O-3的O-3连接在其寡糖链中的D-半乳糖残基。2-(三甲基甲硅烷基)乙基6-O-苯甲酰基-,3-O-苯甲酰基-或3-O-苄基-β-D-吡喃半乳糖苷或2-(三甲基甲硅烷基)乙基2,3,6的糖基化2′,6′-戊-O-苄基-β-乳糖苷(7),与甲基[苯基5-乙酰氨基-8-O-(5-乙酰氨基-4,7,8,9-四-O-乙酰基- 3,5-二甲氧基-D-甘油-α-D-半乳糖-2-壬基吡喃并1',9内酯)-4,7-二-O-乙酰基-3,5-二甲氧基-2-硫代-D-甘油-D-半乳糖-2-nonulopyrano sid] onate(3),使用N-碘琥珀酰亚胺-三氟甲磺酸作为促进剂,得到相应的α糖苷8(32%),13(33%),