6A和6B型肺炎链球菌荚膜多糖的选择性保护三糖构建块的合成。

Synthesis of a selectively protected trisaccharide building block of the capsular polysaccharide of Streptococcus pneumoniae types 6A and 6B.

作者信息

Slaghek T M, van Vliet M J, Maas A A, Kamerling J P, Vliegenthart J F

机构信息

Department of Bio-Organic Chemistry, Utrecht University, The Netherlands.

出版信息

Carbohydr Res. 1989 Dec 21;195(1):75-86. doi: 10.1016/0008-6215(89)85090-6.

DOI:10.1016/0008-6215(89)85090-6

PMID:2636047

Abstract

4-Methoxybenzyl 2,4-di-O-benzyl-3-O-[2,4,6-tri-O-benzyl-3-O-(3,4,6-tri-O-benzyl-alpha-D- galactopyranosyl)-alpha-D-glucopyranosyl]-alpha-L-rhamnopyranoside (22), a building block for the alpha-D-Galp-(1----3)-alpha-D-Glcp-(1----3)-alpha-L-Rhap fragment of the capsular polysaccharides of Streptococcus pneumoniae types 6A and 6B [----2)-alpha-D-Galp-(1----3)-alpha-D-Glcp-(1----3)-alpha-L-Rhap-( 1----X)-D- RibOH-(5-P----]n (6A, X = 3; 6B, X = 4) has been synthesised. Ethyl 3-O-allyl-2,4,6-tri-O-benzyl-1-thio-beta-D-glucopyranoside was coupled with 4-methoxybenzyl 2,4-di-O-benzyl-alpha-L-rhamnopyranoside in ether, using methyl triflate as promoter. The resulting alpha-D-Glcp-(1----3)-alpha-L-Rhap derivative was deallylated with KOBut in N,N-dimethylformamide followed by 0.1M HCl in 9:1 acetone-water. The product was coupled with 3,4,6-tri-O-acetyl-2-O-allyl-alpha,beta-D-galactopyranosyl trichloroacetimidate in ether, using trimethylsilyl triflate, to yield 19. Deacetylation, benzylation, and deallylation then gave 22.

摘要

4-甲氧基苄基 2,4-二-O-苄基-3-O-[2,4,6-三-O-苄基-3-O-(3,4,6-三-O-苄基-α-D-吡喃半乳糖基)-α-D-吡喃葡萄糖基]-α-L-鼠李糖苷(22)，一种用于合成肺炎链球菌6A和6B型荚膜多糖α-D-半乳糖-(1→3)-α-D-葡萄糖-(1→3)-α-L-鼠李糖片段[----2)-α-D-半乳糖-(1→3)-α-D-葡萄糖-(1→3)-α-L-鼠李糖-(1→X)-D-核糖醇-(5-P----]n(6A，X = 3；6B，X = 4)的结构单元已被合成。3-O-烯丙基-2,4,6-三-O-苄基-1-硫代-β-D-吡喃葡萄糖苷乙酯与4-甲氧基苄基 2,4-二-O-苄基-α-L-鼠李糖苷在乙醚中反应，使用三氟甲磺酸甲酯作为促进剂。所得的α-D-葡萄糖-(1→3)-α-L-鼠李糖衍生物在N，N-二甲基甲酰胺中用叔丁醇钾脱烯丙基，然后在9:1的丙酮-水中用0.1M盐酸处理。产物与3,4,6-三-O-乙酰基-2-O-烯丙基-α,β-D-吡喃半乳糖基三氯乙酰亚胺酯在乙醚中反应，使用三氟甲磺酸三甲基硅酯，得到19。然后进行脱乙酰化、苄基化和脱烯丙基反应得到22。