Chemoselective activation of ethyl <i>vs</i>. phenyl thioglycosides: one-pot synthesis of oligosaccharides
作者:Cian Mc Carthy、Xiangming Zhu
DOI:10.1039/d0ob01606c
日期:——
pattern. Both armed and disarmed thioglycosides exhibited high chemoselectivity towards the promoter system. Chemoselective glycosylation was subsequently applied to one-potsynthesis, thus providing an efficient means to oligosaccharides.
An armed–disarmed approach for blocking aglycon transfer of thioglycosides
作者:Zhitao Li、Jeffrey C. Gildersleeve
DOI:10.1016/j.tetlet.2006.11.126
日期:2007.1
Th ioglycosides are used frequently as glycosyl donors and as mimetics of O-glycosides. While being very useful, thioglycosides are prone to a detrimental side reaction referred to as aglycon transfer. In this letter, it is shown that aglycon transfer can be blocked by matching thioglycoside-containing acceptors with more armed glycosyl donors. Published by Elsevier Ltd.
Synthesis of the Carbohydrate Moiety of Glycoproteins from the Parasite Echinococcus granulosus and Their Antigenicity against Human Sera
6-O-benzylidene-2-deoxy-α-d-galactopyranoside as a common glycosyl acceptor. The synthesis of the tetrasaccharide and the pentasaccharide was improved from the viewpoint of reducing the number of synthetic steps and increasing the total yield by changing from stepwise condensation to block synthesis. Moreover, hexasaccharide E, which contains the oligosaccharide sequence which occurs in E. granulosus
含有细粒棘球绦虫糖蛋白碳水化合物部分的生物素标记寡糖部分的立体控制合成已经完成。三糖 Galβ1-3Galβ1-3GalNAcα1-R ( A )、四糖 Galα1-4Galβ1-3Galβ1-3GalNAcα1-R ( B ) 和五糖 Galα1-4Galβ1-3Galβ1-3Galβ1-3GalNAcα1-R ( C ),(R = 生物素化探针)使用5-(甲氧基羰基)戊基2-叠氮基-4,6- O-亚苄基-2-脱氧-α- d-吡喃半乳糖苷作为常见糖基受体,通过逐步缩合和/或嵌段合成法合成。通过从逐步缩合变为嵌段合成,从减少合成步骤数和增加总收率的角度来看,改进了四糖和五糖的合成。此外,由三糖D合成了六糖E ,其含有细粒棘球绦虫中存在的寡糖序列。我们通过酶联免疫吸附测定(ELISA)检查了这五种寡糖的抗原性。虽然C – E化合物对囊性包虫病 (CE) 患者血清不表现出抗原性,但化合物B 、