146773-71-9Relevant academic research and scientific papers
Solvent-free, under air selective synthesis of α-glycosides adopting glycosyl chlorides as donors
Bedini, Emiliano,Iadonisi, Alfonso,Traboni, Serena,Vessella, Giulia
, p. 5157 - 5163 (2020/07/23)
α-Glycosides are highly relevant synthetic targets due to their abundance in natural oligosaccharides involved in many biological processes. Nevertheless their preparation is hampered by several issues, due to both the strictly anhydrous conditions typically required in glycosylation procedures and the non-trivial achievement of high α-stereoselectivity, one of the major challenges in oligosaccharide synthesis. In this paper we report a novel and efficient approach for the highly stereoselective synthesis of α-glycosides. This is based on the unprecedented solvent-free combination of triethylphosphite, tetrabutylammonium bromide and N,N-diisopropylethylamine for the activation of glycosyl chlorides under air. Despite the relative stability of glycosyl chlorides with respect to more reactive halide donors, the solvent-free procedure allowed a wide set of α-glycosides, including biorelevant fragments, to be obtained in much shorter times compared with similar glycosylation approaches in solution. The presented method features a wide target scope and functional group compatibility, also serving with partially disarmed substrates, and it does not require a high stoichiometric excess of reagents nor the preparation of expensive precursors. The solvent-free glycosylation can be even directly performed from 1-hydroxy sugars without purification of the in situ generated chloride, providing an especially useful opportunity in the case of highly reactive and labile glycosyl donors. This journal is
Facile glycosylation strategy with two-stage activation of allyl glycosyl donors. Application to concise synthesis of Shigella flexneri serotype y O-antigen
Wang, Yun,Zhang, Xin,Wang, Pengfei
supporting information; experimental part, p. 4322 - 4328 (2010/11/18)
A practical, useful glycosylation method employing only allyl glycoside building blocks has been developed. The donor's glycosylation reactivity is turned on via isomerization of its anomeric allyl protecting group into the corresponding prop-1-enyl moiet
Simple glycosylation reaction of allyl glycosides
Wang, Pengfei,Haldar, Pranab,Wang, Yun,Hu, Ayou
, p. 5870 - 5873 (2008/02/09)
(Chemical Equation Presented) A simple glycosylation strategy employing only allyl glycosides is described. In a one-pot fashion, an allyl glycoside is first isomerized to the reactive 1-prop-en-yl glycoside intermediate, which subsequently undergoes glyc
Dehydrative Glycosylation Using Heptabenzyl Derivatives of Glucobioses and Lactose
Koto, Shinkiti,Morishima, Naohiko,Shichi, Sonoko,Haigoh, Hisamitsu,Hirooka, Motoko,et al.
, p. 3257 - 3274 (2007/10/02)
Dehydrative glycosylations of the 2-, 3-, 4-, and 6-OH groups of D-glucopyranose with hepta-O-benzyl derivatives of glucobioses (O-D-glucopyranosyl-(1->n)-D-glucopyranose; n = 2, 3, 4, or 6) and lactose, in the presence of a ternary mixture of p-nitrobenzenesulfonyl chloride, silver trifluoromethanesulfonate, and triethylamine in dichloromethane showed that the selectivity of the reaction depended on the anomeric configuration and the linking position to the reducing tribenzylglucose moiety of the nonreducing tetrabenzylglucosyl residue and on the class of the OH group to be glycosylated.The use of a quaternary mixture of p-nitrobenzenesulfonyl chloride, silver trifluoromethanesulfonate, N,N-dimethylacetamide, and triethylamine made all but the β(1->2)-linked biosyl donor undergo α-condensation.Several new linear trisaccharides were obtained via debenzylation of the condensates.
