C-Glycosyl Tyrosines. Synthesis and Incorporation into <i>C</i>-Glycopeptides
作者:Alan J. Pearce、Sharn Ramaya、Simon N. Thorn、Graham B. Bloomberg、Daryl S. Walter、Timothy Gallagher
DOI:10.1021/jo990253e
日期:1999.7.1
The synthesis of the Fmoc-protected C-glycosyl tyrosines 1 and 2, together with two other related C-glycosyl tyrosines, has been achieved. Key reactions involved (i) the reaction of a glycal with an organozinc reagent (carrying an aryl iodide function) in the presence of a Lewis acid to establish the C-glycosyl linkage and (ii) subsequent cross coupling of the aryl iodide to an alanyl zinc reagent
已经实现了Fmoc保护的C-糖基酪氨酸1和2以及另外两种相关的C-糖基酪氨酸的合成。关键反应涉及(i)在路易斯酸存在下,糖基与有机锌试剂(具有芳基碘化物的功能)反应,以建立C-糖基键合;以及(ii)随后将芳基碘化物交叉偶联到丙氨酰基上锌试剂(在Pd(0)催化剂存在下)完成α-氨基酸部分的构建。使用固相肽合成方法,将两个甘露糖基衍生物1(显示为L-Tyr [C-Ac(4)-alpha-D-Man])(含四个甘氨酸)掺入线性六肽中3,然后将其转换为C(2)对称环状寡肽4。