Synthesis of a Core Trisaccharide as a Versatile Building Block for N-Glycans and Glycoconjugates
作者:Carlo Unverzagt
DOI:10.1002/chem.200390156
日期:2003.3.17
N-linked oligosaccharides from glycoproteins (N-glycans) can be conveniently assembled with a buildingblockapproach. A protected form of the core trisaccharide (beta-mannosyl chitobiose) was identified as a keybuildingblock. The chitobiose part of the core trisaccharide was built from a glycosyl fluoride, which served as a precursor for the reducing GlcNAc azide and the inner GlcNAc moiety. Beta-mannosylation
N‐glycans are suitable for the late introduction of a bisecting GlcNAc. This integrated strategy permits for the first time the use of a single approach for multiantennary N‐glycans as well as their bisected derivatives via imidates, with unprecedented yields even in a one‐pot double glycosylation. With this new method, rare N‐glycans of the bisected type can be obtained readily, thereby providing defined
Chemoselective Ligation Applied to the Synthesis of a Biantennary <i>N</i>-Linked Glycoform of CD52
作者:Matthew R. Pratt、Carolyn R. Bertozzi
DOI:10.1021/ja029346v
日期:2003.5.1
here a strategy for the synthesis of N-linked glycopeptide analogues that replace the glycosidic linkages extending from the core pentasaccharide with thioethers amenable to construction by chemoselective ligation. The key building block, a pentasaccharide-Asn analogue containing two thiol residues, was incorporated into CD52 by 9-fluorenylmethoxycarbonyl (Fmoc)-based solid-phase peptide synthesis. An
我们在这里报告了一种合成 N 连接糖肽类似物的策略,该类似物用适合通过化学选择性连接构建的硫醚代替从核心五糖延伸的糖苷键。通过基于 9-芴基甲氧基羰基 (Fmoc) 的固相肽合成,关键构建块是包含两个硫醇残基的五糖-Asn 类似物。然后通过用 N-溴乙酰胺三糖对该糖肽进行烷基化,很容易生成十一糖模拟物。使用该技术完成了复杂类型 N 连接糖肽模拟物的快速组装。
A new strategy for the synthesis of the core trisaccharide of asparagine-linked sugar chains
The core trisaccharide common to all asparagine-linked glycoprotein oligosaccharides was synthesized using two novel processes: 1) regioselective acetylation using lipase, and 2) inversion of the C-2 hydroxyl group of the glucose residue in a glucosyl chitobiose derivative to produce the corresponding mannosyl chitobiose derivative.
biantennary N-linked oligosaccharides from glycoproteins (N-glycans) has been developed. Starting from a core trisaccharide (beta-mannosyl chitobiose) containing a benzylidene-protected beta-mannoside, the attachment of the disaccharide building blocks for the antennae can be performed in a doubleregio- and stereoselective manner. A short synthesis of a GlcNPhtbeta1,2Man donor was developed. The benzylidene