challenging β-rhamnosyl linkage in its structure was achieved stereospecifically through naphthylmethyl-assisted intramolecular aglycon delivery (IAD). The remaining 1,2-trans glycosylation reactions were executed in excellent yields and stereoselectivity based on neighboring group participation. The phosphoglycerol branch was installed by the phosphoramidite method with benzylidene-protected glycerol 2-phosphoramidite
                                    有效合成肺炎链球菌血清型23F荚膜
多糖(CPS)的
生物重复单元的3-
氨丙基糖苷。合成靶含有带有
磷酸甘油支链的四糖。它的
寡糖主链是通过线性糖基化组装的,其结构中具有挑战性的β-
鼠李糖基键是通过
萘甲基甲基辅助的分子内糖苷配基传递(IAD)立体定向实现的。其余的1,2-反式基于邻近基团的参与,糖基化反应以优异的产率和立体选择性进行。通过亚
磷酰胺法,以亚苄基保护的
甘油2-亚
磷酰胺为底物,安装
磷酸甘油支链。最终,目标分子以17个最长的线性步骤由
单糖结构单元合成,总产率为3.85%。此外,合成靶标在其还原端还包含一个游离
氨基,有助于其与其他分子结合,用于各种
生物学研究和应用。