Stereoselective Glycosylation of Thioglycosides Promoted by Respective Combinations of<i>N</i>-Iodo- or<i>N</i>-Bromosuccinimide and Trityl Tetrakis(pentafluorophenyl)borate. Application to One-Pot Sequential Synthesis of Trisaccharide
作者:Kazuya Takeuchi、Takayuki Tamura、Teruaki Mukaiyama
DOI:10.1246/cl.2000.124
日期:2000.2
New highly effective promoter system for the glycosylation of thioglycoside, the combined use of stoichiometric amount of either N-iodosuccinimide or N-bromosuccinimide and a catalytic amount of TrB(C6F5)4, was developed and was successfully applied to the one-pot sequential synthesis of trisaccharides. In the first glycosylation step, 3,4,6-tri-O-benzyl-2-O-p-toluoyl-β-D-glucopyranosyl phenylcarbonate
开发了硫糖苷糖基化的新型高效促进剂系统,结合使用化学计量量的 N-碘代琥珀酰亚胺或 N-溴代琥珀酰亚胺和催化量的 TrB(C6F5)4,并成功应用于一锅法顺序合成三糖。在第一个糖基化步骤中,3,4,6-tri-O-benzyl-2-Op-toluoyl-β-D-glupyranosyl phenylcarbonate 在催化量的 TrB(C6F5)4 存在下用硫代糖苷处理,并且通过将 N-碘代琥珀酰亚胺或 N-溴代琥珀酰亚胺进一步添加到最初得到的反应混合物中,以一锅方式提供相应的三糖,从而进行随后的甲基 α-D-糖苷糖基化。