report thiouracil-catalyzed α-selective O-glycosylations employing easily accessible glycosyl trichloroacetimidate donors without using any co-catalyst or additive. A variety of alcohol nucleophiles including saccharides, and amino acids with different protecting groups containing glycosyl trichloroacetimidate donors were successfully α-glycosylated using an operationally simple protocol. Moreover, mechanistic
在此,我们报道了
硫氧
嘧啶催化的α-选择性O-糖基化,使用易于获得的糖基三
氯乙
酰亚胺酯供体,而不使用任何助催化剂或添加剂。使用操作简单的方案成功地将多种醇亲核试剂(包括
糖类和具有不同保护基团的含有糖基三
氯乙
酰亚胺酯供体的
氨基酸)进行α-糖基化。此外,机理研究表明
硫氧
嘧啶在此糖基化过程中起到布朗斯台德酸/碱催化作用。