Alkenyl β-d-galactopyranoside derivatives as efficient chiral templates in stereoselective cyclopropanation and epoxidation reactions
作者:José M. Vega-Pérez、Ignacio Periñán、Carlos Palo-Nieto、Margarita Vega-Holm、Fernando Iglesias-Guerra
DOI:10.1016/j.tetasy.2009.12.003
日期:2010.1
The synthesis of a wide range of alkenyl 4,6-O-(S)-benzylidene-beta-D-galactopyranosides is described. The cyclopropanation and epoxidation reactions of these compounds were developed. Cyclopropanation reactions took place with high stereoselectivity giving diastereomeric excesses of up to 100%. As a part Of Our aim in studying hydroxyl-directed reactions, their epoxidation with m-CPBA was carried out High diastereomeric excesses (80-100%) were obtained when the hydroxyl group at C-2 of the auxiliary was unprotected The beta-D-galactopyranoside moiety constitutes as an interesting auxiliary, due to its efficient chirality transfer capability as well as providing a way to obtain a variety of glycolipid derivatives (c) 2009 Elsevier Ltd All rights reserved.
Stereoselective Dihydroxylation Reaction of Alkenyl β-D-Hexopyranosides: A Methodology for the Synthesis of Glycosylglycerol Derivatives and 1-O-Acyl-3-O-β-D-glycosyl-sn-glycerol Analogues
作者:José M. Vega-Pérez、Carlos Palo-Nieto、Ignacio Periñán、Margarita Vega-Holm、José M. Calderón-Montaño、Miguel López-Lázaro、Fernando Iglesias-Guerra
DOI:10.1002/ejoc.201101539
日期:2012.2
A variety of new glycosylglycerolderivatives have been prepared by stereoselectivedihydroxylation of a range of alkenyl β-D-hexopyanosides under Donohoe's conditions. We have studied the relationship between the diastereoisomeric excess and the structural features of the precursor (sugar and alkenyl moieties). The stereochemical yields demonstrated that the presence of a hydrogen-bond donor group