Synthesis and transformations of [1,2-O-isopropylidene-alpha-D-erythro (and alpha-D-ribo)furanose]-3-spiro-3'-(4'-amino-5 H-2',3'dihydroisothiazole-1',1'-dioxide) derivatives

摘要

The carbanion-mediated sulfonamide cyclisations (CSIC protocols) of glyco-alpha-sulfonamidonitriles derived from readily available uloses 1A and 1B have been investigated using different bases (potassium carbonate, cesium carbonate, LDA and n-BuLi). As a result, a series of enantiomerically pure [1,2-O-isopropylidene-alpha-D-erythro (and alpha-D-ribo)furanose]-3-spiro-3'-(4'-amino-5'H-2',3'-dihydroisothiazole-1',1'-dioxide) derivatives have been prepared and isolated in good yields. (C) 2004 Elsevier Ltd. All rights reserved.