The School of Chemistry and Molecular Biosciences, University of Queensland, St Lucia, QLD 4072, Australia.
Carbohydr Res. 2013 Apr 19;371:68-76. doi: 10.1016/j.carres.2013.01.008. Epub 2013 Feb 12.
Poly-N-acetylglucosamine (PNAG) saccharides are an important constituent of bacterial biofilms, such as those produced by Staphylococcus aureus. We have developed a simple two-step iterative method for the synthesis of β-(1→6)-glucosamine oligosaccharides that are structurally similar to PNAG. We illustrate the method with the formation of a pentasaccharide. The key building block is an orthogonally protected N-trifluoroacetamido thioglycoside donor that was added in succession to a glycosyl acceptor, enabling efficient glycosylation of the growing chain. In the second step of the iterative cycle, this building block is quantitatively deprotected at the C-6-hydroxyl position, ready for the next saccharide addition. Building from an azido-functionalised GlcNAc monosaccharide acceptor, the pentasaccharide was synthesised in seven steps in an overall yield of 25%.
聚-N-乙酰葡糖胺（PNAG）糖是细菌生物膜的重要组成部分，如金黄色葡萄球菌产生的生物膜。我们开发了一种简单的两步迭代法来合成与 PNAG 结构相似的β-（1→6）-葡糖胺低聚糖。我们以五糖的形成来说明该方法。关键的结构单元是一个正交保护的 N-三氟乙酰氨基硫代糖苷供体，它依次添加到糖基受体上，从而实现了生长链的有效糖基化。在迭代循环的第二步中，该结构单元在 C-6-羟基位置被定量脱保护，为下一个糖基的添加做好准备。从叠氮功能化的 GlcNAc 单糖受体开始，五糖在七步总收率为 25%的条件下合成。
