Phenylsulfonylethylidene (PSE) acetals as atypical carbohydrate-protective groups
作者:Florence Chéry、Patrick Rollin、Ottorino De Lucchi、Sergio Cossu
DOI:10.1016/s0040-4039(00)00199-4
日期:2000.4
We introduce a new class of arylsulfonylated cyclic acetals derived from carbohydrate structures which are synthesized with high yields under basic conditions. Deprotection methods for such acetals are also investigated. (C) 2000 Elsevier Science Ltd. All rights reserved.
Carbohydrate-derived PSE acetals: controlled base-induced ring cleavage
作者:Florence Chéry、Elena Cabianca、Arnaud Tatibouët、Ottorino De Lucchi、Patrick Rollin
DOI:10.1016/j.tet.2011.11.009
日期:2012.1
Retro-Michael type reactions applied to PSE acetals protecting monosaccharides led either to complete removal or to ring-cleavage. In protic medium, application of standard basic conditions resulted in acetal deprotection, while the use of butyl lithium in aprotic medium allowed controlled ring-cleavage. A regio-and stereoselective C- over O-alkylation was observed during the process. Furthermore, depending on the substrates and the reaction conditions involved, new carbohydrate-derived beta-alkoxyvinyl sulfones were obtained with varying regioselectivity. (C) 2011 Elsevier Ltd. All rights reserved.