Synthetic Studies on Sialoglycoconjugates. 5: A Facile, Regio and Stereoselective Synthesis of Ganglioside GM4 and Its Position Isomer1
Synthetic Studies on Sialoglycoconjugates. 5: A Facile, Regio and Stereoselective Synthesis of Ganglioside GM4 and Its Position Isomer1
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唾液酸糖缀合物的合成研究。
DOI：
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发表时间：
1989
期刊：
影响因子：
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通讯作者：
A. Hasegawa
中科院分区：
文献类型：
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作者：
T. Murase;A. Kameyama;K. Kartha;H. Ishida;M. Kiso;A. Hasegawa
摘要合成了神经节苷脂GM 4及其位置异构体。以2-（三甲基硅基）乙基β-D-吡喃半乳糖苷（1）为原料，经选择性的3-O-苄基化、6-O-苯甲酰基化和去苄基化，或经3，4-O-异丙基化、6-O-苯甲酰基化和O-脱异丙基化，得到2-（三甲基硅基）乙基6-O-苯甲酰基-β-D-吡喃半乳糖苷（4）。1通过选择性苯甲酰化得到2-（三甲基硅基）乙基3-O-苯甲酰基-β-D-吡喃半乳糖苷（5）。4或5与甲基α-硫代糖苷衍生物（9）的糖苷化反应，所述甲基α-硫代糖苷衍生物（9）衍生自甲基5-乙酰氨基-4，7，8，9-四-O-乙酰基-2-S-乙酰基-3，5-脱氧-2-硫代-D-甘油基-a-D-半乳糖基-2-吡喃壬糖酸酯（8），使用二甲基甲酰胺通过选择性S-脱乙酰化和随后的S-甲基化进行。（甲硫基）锍三氟甲磺酸盐（DMTST）分别得到相应的Neu 5Ac的α-糖苷（10，12）。偶联三氯乙酰亚胺酯（15，17），从10和12获得的O-乙酰化，选择性去除2-（三甲基甲硅烷基）乙基，和...
Abstract Ganglioside GM4 and its positional isomer have been synthesized. 2-(Trimethylsilyl)ethyl 6-O-benzoyl-β-D-galactopyranoside (4) was prepared from 2-(trimethylsilyl)ethyl β-D-galactopyranoside (1) by selective 3-O-benzylation, 6-O-benzoylation and subsequent removal of the benzyl group, or by 3,4-O-isopropylidenation, 6-O-benzoylation and O-deisopropylidenation. 2-(Trimethylsilyl)ethyl 3-O-benzoyl-β-D-galactopyranoside (5) was obtained by selective benzoylation of 1. The glycosidation of 4 or 5 with the methyl α-thioglycoside derivative (9), derived from methyl 5-acetamido-4,7,8,9-tetra-0-acetyl-2-S-acetyl-3,5-dTdeoxy-2-thio-D-glycero-a-D-galacto-2-nonulopyranosonate (8) via selective S-deacetylation and subsequent S-methylation, using dimethyl(methylthio)sulfonium triflate (DMTST) gave the corresponding α-glycosides (10, 12) of Neu5Ac, respectively. Coupling of the trichloroacetimidates (15, 17), obtained from 10 and 12 by O-acetylation, selective removal of the 2-(trimethylsilyl)ethyl group, and ...