Why Is Direct Glycosylation with <i>N</i>-Acetylglucosamine Donors Such a Poor Reaction and What Can Be Done about It?
作者:Mikkel H. S. Marqvorsen、Martin J. Pedersen、Michelle R. Rasmussen、Steffan K. Kristensen、Rasmus Dahl-Lassen、Henrik H. Jensen
DOI:10.1021/acs.joc.6b02305
日期:2017.1.6
chemical glycosylation is challenging since direct reactions are low yielding. This issue, generally agreed upon to be caused by an intermediate 1,2-oxazoline, is often bypassed by introducing extra synthetic steps to avoid the presence of the NHAc functional group during glycosylation. The present paper describes new fundamental mechanistic insights into the inherent challenges of performing direct glycosylation
Selective pivaloylation of 2-acetamido-2-deoxy sugars
作者:Đurđica Ljevaković、Srdanka Tomić、Jelka Tomašić
DOI:10.1016/0008-6215(88)84003-5
日期:1988.11
Selectivepivaloylation of 2-acetamido-2-deoxy-D-glucose, its methyl alpha- and beta-glycosides, and the methyl alpha-glycoside of N-acetyl-D-muramic acid under various conditions has been studied. The structures of the products were established by 1H-n.m.r. spectroscopy and acetylation. The orders of acylation, HO-6 greater than HO-3 greater than HO-1 greater than HO-4 for 2-acetamido-2-deoxy-D-glucose