Efficient synthesis of 3, 6-dideoxy-beta-D-arabino-hexopyranosyl-terminated LacdiNac glycan chains of the Trichinella spiralis parasite.
Efficient synthesis of 3, 6-dideoxy-beta-D-arabino-hexopyranosyl-terminated LacdiNac glycan chains of the Trichinella spiralis parasite.
复制标题
旋毛虫寄生虫的 3, 6-二脱氧-β-D-阿拉伯-吡喃己糖基封端的 LacdiNac 聚糖链的高效合成。
DOI：
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发表时间：
2000
影响因子：
3.6
通讯作者：
D. Bundle
中科院分区：
文献类型：
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作者：
Mark Nitz and;D. Bundle
据报道，旋毛虫 N-连接聚糖的线性三糖表位的合成，其形式适合糖缀合物形成。三糖含有合成上具有挑战性的 LacdiNAc [β-GalpNAc(1-->4)-β-GlcpNAc] 元件，以及末端 3,6-二脱氧-β-D-阿拉伯-吡喃己糖（tyvelose）残基。描述了一种正交保护策略，该策略允许保护和操作二糖β-GalNAc(1→4)-β-GlcNAc 中存在的三个氨基以及用于制备新糖缀合物的系链。通过引入双脱氧己糖单元作为 β-D-核糖-吡喃己糖苷（帕拉糖），然后通过氧化还原序列以高非对映异构体过量生成 β-D-阿拉伯构型，以优异的产率生成 β 连接的双脱氧己糖。利用对甲氧基苯基糖苷，通过一系列高产步骤从葡萄糖合成所需的双脱氧己糖供体。
The synthesis of a linear trisaccharide epitope of the Trichinella spiralis N-linked glycan, in a form amenable to glycoconjugate formation, is reported. The trisaccharide contains the synthetically challenging LacdiNAc [beta-GalpNAc(1-->4)-beta-GlcpNAc] element, as well as a terminal 3,6-dideoxy-beta-D-arabino-hexopyranose (tyvelose) residue. An orthogonal protection strategy is described, which permits the protection and manipulation of three amino groups present in the disaccharide beta-GalNAc(1-->4)-beta-GlcNAc and the tether used to prepare neoglycoconjugates. The beta-linked dideoxyhexose was generated in excellent yield by the introduction of the dideoxyhexose unit as a beta-D-ribo-hexopyranoside (paratose) followed by an oxidation-reduction sequence to generate the beta-D-arabino configuration in high diastereomeric excess. The required dideoxyhexose donor was synthesized in a series of high-yielding steps from glucose utilizing the p-methoxyphenyl glycoside.