摘要:
A new methodology for the preparation of carbohydrates locked in a B-1,B-4 boat conformation is presented. The constrained molecules thus obtained are functionalized at the anomeric position by iodo-, fluoro-, hydroxyl- or/and phosphono-methylene moieties. A remarkable diastereoselective opening of these quaternary acetals was also observed under non-acidic conditions. (c) 2007 Elsevier Ltd. All rights reserved.