Tetrasaccharide cap present in lipophosphoglycan of the Leishmania donovani responsible for visceral Leishmaniaisis is synthesized as a fully protected propargyl glycoside. AuBr3 mediated selective glycosylation of propargyl 1,2-orthoester in the presence of propargyl glycoside is employed as a key step to obtain propargyl containing oligomers. Further, propargyl tetrasaccharide is connected with a long chain hydrocarbon containing azidothiol functionality situated at two terminal ends via ‘click’ reaction.
在导致内脏利什曼病的唐氏利什曼原虫脂
磷聚糖中存在的四糖帽被合成为完全保护的
丙炔糖苷。在
丙炔糖苷存在的情况下,采用
AuBr3 介导的
丙炔 1,2-orthoester 选择性糖基化是获得含
丙炔的低聚物的关键步骤。此外,
丙炔四糖通过 "点击 "反应与位于两个末端的含有
叠氮硫醇官能团的长链碳氢化合物连接。