Synthesis of β-analogues of C-mannosyltryptophan, a novel C-glycosylamino acid found in proteins
作者:Toshio Nishikawa、Yuya Koide、Akira Kanakubo、Hiroshi Yoshimura、Minoru Isobe
DOI:10.1039/b516282c
日期:——
α-C-Mannosyltryptophan (α-C-Man-Trp) has been found to be a novel post-translational modification of tryptophan found from some biologically important glycoproteins. In order to analyze the biological functions of α-C-Man-Trp, we have developed an efficient synthetic strategy for α-C-Man-Trp and its glucose and galactose analogues, starting from α-C-glycosidation of the corresponding hexapyranoside derivatives with tinacetylene. According to the synthetic routes, we describe here syntheses of β-anomers of C-Man-Trp, and its glucose and galactose analogues from the corresponding β-C-glycosylacetylenes. During this study, we have developed a highly stereocontrolled synthesis of β-C-mannosylacetylene that is required for the synthesis of β-C-Man-Trp, while the precedented method gave an anomeric mixture of the C-mannosylacetylene. The synthetic C-Man-Trp and its analogues were analyzed by HPLC.
α-C-甘露糖基色氨酸(α-C-Man-Trp)被发现是一种新的色氨酸翻译后修饰,存在于一些生物重要的糖蛋白中。为了分析α-C-Man-Trp的生物功能,我们开发了一种高效的合成策略,用于α-C-Man-Trp及其葡萄糖和半乳糖类似物,从对应的六糖派拉诺糖衍生物与乙炔锡的α-C-糖苷化反应开始。根据合成路线,我们在此描述了从相应的β-C-糖苷乙炔衍生物合成β-异构体的C-Man-Trp及其葡萄糖和半乳糖类似物。在这项研究中,我们开发了一种高度立体选择性合成β-C-甘露糖基乙炔的方法,这是合成β-C-Man-Trp所必需的,而先前的方法则给出了C-甘露糖基乙炔的异构体混合物。合成的C-Man-Trp及其类似物通过高效液相色谱(HPLC)进行了分析。