Lewis acid promoted anomerisation of alkyl O- and S-xylo-, arabino- and fucopyranosides
作者:Lisa M. Doyle、Fiach B. Meany、Paul V. Murphy
DOI:10.1016/j.carres.2018.11.010
日期:2019.1
and 6-deoxyhexopyranosides, such as those from d-xylose, l-arabinose and l-fucose are components of natural products, oligosaccharides or polysaccharides. Lewis acid promoted anomerisation of some of their alkyl O- and S-glycopyranosides is reported here. SnCl4 was more successful than TiCl4, with the latter giving the glycosyl chloride by-product in some cases, and both were superior to BF3OEt2. Kinetics
A mild and one-pot protocol for the efficient and stereoselective synthesis of 1,2-trans-aldosyl mercaptans is presented. (c) 2007 Elsevier Ltd. All rights reserved.
Stereoselective Epimerizations of Glycosyl Thiols
作者:Lisa M. Doyle、Shane O’Sullivan、Claudia Di Salvo、Michelle McKinney、Patrick McArdle、Paul V. Murphy
DOI:10.1021/acs.orglett.7b02760
日期:2017.11.3
Glycosyl thiols are widely used in stereoselective S-glycoside synthesis. Their epimerization from 1,2-trans to 1,2-cis thiols (e.g., equatorial to axial epimerization in thioglucopyranose) was attained using TiCl4, while SnCl4 promoted their axial-to-equatorial epimerization. The method included application for stereoselective β-d-manno- and β-l-rhamnopyranosyl thiol formation. Complex formation explains