Dual-Participation Protecting Group Solves the Anomeric Stereocontrol Problems in Glycosylation Reactions
作者:Hui Liu、Thomas Hansen、Si-Yu Zhou、Guo-En Wen、Xu-Xue Liu、Qing-Ju Zhang、Jeroen D. C. Codée、Richard R. Schmidt、Jian-Song Sun
DOI:10.1021/acs.orglett.9b03321
日期:2019.11.1
The 2,2-dimethyl-2-(ortho-nitrophenyl)acetyl (DMNPA) group permits, via robust neighboring group participation (NGP) or long distance participation (LDP) effects, the stereocontrolled 1,2-trans, 1,2-cis, as well as β-2,6-dideoxy glycosidic bond generation, while suppressing the undesired orthoester byproduct formation. The robust stereocontrol capability of the DMNPA is due to the dual-participation
2,2-二甲基-2-(邻-硝基苯基)乙酰基(DMNPA)基团可通过强大的邻近基团参与(NGP)或长距离参与(LDP)效应实现立体控制的1,2-反式,1,2-顺式,以及β-2,6-二脱氧糖苷键的生成,同时抑制了不希望的原酸酯副产物的形成。DMNPA强大的立体控制能力归因于酯官能团和硝基的双重参与作用,这已通过对照反应和DFT计算得到证实,并通过X射线光谱法得到进一步证实。