A concise synthetic strategy has been developed for the synthesis of the pentasaccharide repeating unit of the cell wall O-antigen of Escherichia coli O43 strain involving stereoselective β-D-mannosylation and α-L-fucosylation using corresponding trichloroacetimidate intermediates and perchloric acid supported over silica (HClO₄-SiO₂) as glycosylation promoter. The yield and stereoselectivity of the glycosylations were very good.

中文翻译：

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大肠杆菌O43菌株细胞壁O抗原的五糖重复单元的直接合成。

已经开发了一种简洁的合成策略，用于合成大肠杆菌O43 菌株细胞壁O-抗原的五糖重复单元，涉及立体选择性 β-D-甘露糖基化和 α-L-岩藻糖基化，使用相应的三氯乙酰亚胺中间体和高氯酸负载在二氧化硅上(HClO ₄ -SiO ₂ )作为糖基化促进剂。糖基化的产率和立体选择性非常好。