Stereoselective Synthesis of 2-Deoxyglycosides from Sulfanyl Alkenes by Consecutive “One Pot” Cyclization and Glycosylation Reactions
作者:Miguel A. Rodríguez、Omar Boutureira、M. Isabel Matheu、Yolanda Díaz、Sergio Castillón
DOI:10.1002/ejoc.200601115
日期:2007.5
2-Deoxy-2-iodopyranosides 3, and 9–12 were synthesized from sulfanyl alkenes using a “onepot” consecutive cyclization–glycosylation process. Compared with the stepwise procedure, the “onepot” process gave significantly improved yields with similar or slightly lower selectivities. The “one
Stereoselective Synthesis of 2-Deoxy-2-phenylselenenyl Glycosides from Furanoses: Implication of the Phenylselenenyl Group in the Stereocontrolled Preparation of 2-Deoxy-ribo- and 2-Deoxy-xylo-oligosaccharides
作者:Omar Boutureira、Miguel A. Rodríguez、David Benito、M. Isabel Matheu、Yolanda Díaz、Sergio Castillón
DOI:10.1002/ejoc.200700161
日期:2007.7
were evaluated as a class of glycosyl donors that provide access to 2-deoxyglycosides from furanoses. This short synthetic route involves olefination, selenonium ion mediated 6-endo cyclization and glycosylation reactions. The cyclization reaction proceeds with complete regio- and stereoselectivity, which are enhanced by employing 3,4-O-isopropylidene as a cyclic bifunctional protecting group. The implication
Studies on the Zn(II)-mediated electrophilic selenocyclization and elimination of 3,4-O-isopropylidene-protected hydroxyalkenyl sulfides: synthesis of a 2-phenylselenenyl glycal
作者:Omar Boutureira、Miguel A. Rodríguez、Yolanda Díaz、M. Isabel Matheu、Sergio Castillón
DOI:10.1016/j.carres.2010.03.001
日期:2010.5
Herein, we describe a mild and efficient Zn(II)-mediated electrophilic selenocyclization reaction of readily available and stable 3,4-O-isopropylidene-protected hydroxyalkenyl sulfides to 2-deoxy-2-phenylselenenyl-1-thio-glycosides This material was transformed into a 2-phenylselenenyl glycal in a controlled manner using an activation-elimination sequence (C) 2010 Elsevier Ltd. All rights reserved
Stereoselective Synthesis of 2-Deoxy-2-iodo-glycosides from Furanoses. A New Route to 2-Deoxy-glycosides and 2-Deoxy-oligosaccharides of <i>r</i><i>ibo </i>and <i>x</i><i>ylo</i> Configuration
procedure involves three reactions: Wittig−Horner olefination to give alkenyl sulfanyl derivatives, electrophilic iodine-induced cyclization to give phenyl 2-deoxy-2-iodo-1-thio-hexo-glycosides, and glycosylation. Protected furanoses 1, 3, and 6−11, which include examples of the four possible isomeric configurations of furanoses, were reacted with diphenyl phenylsulfanylmethyl phosphine oxide to give the
Reaction of methyl- and phenylthiomethylidene phosphoranes 1 and 2 with a variety of reducing sugars has been explored. Furano-type carbohydrates afforded with good yields the corresponding open-chain vinyl sulfides, whereas pyrano derivatives produced elimination compounds together with the expected vinyl sulfides, depending on the nature of the protective groups.