Article ID | Journal | Published Year | Pages | File Type |
---|---|---|---|---|
10606097 | Carbohydrate Research | 2019 | 7 Pages |
Abstract
Acid-catalysed methanolysis of 3,4,5,6-tetra-O-acetyl-1,2-dideoxy-l-arabino-hex-1-enitol proceeds via a cascade set of consecutive reactions resulting in its regiospecific conversion to a mixture of α- and β-C-l-arabinofuranosylmethanal dimethyl acetals and a mixed internal methyl acetal. Structures of the final products of the overall process provide unique evidence that a kinetically controlled, five-membered-ring closure precedes a six-membered-ring closure in reversible systems capable of giving both five-membered and six-membered all-sp3-atom rings. Determination of the reaction intermediate enabled extension of the Nef reaction to C-glycosylnitromethanes. Protonated aci-nitro forms of C-glycosylnitromethanes that are resistant to the Nef reaction in aqueous acidic media undergo a modified Nef reaction in acidified methanol, and the corresponding C-glycosylmethanal dimethyl acetals with α-l-arabinopyranosyl, β-d-glucopyranosyl, β-d-galactopyranosyl, β-d-mannopyranosyl and β-l-rhamnopyranosyl configurations were obtained in moderate yields.
Keywords
Related Topics
Physical Sciences and Engineering
Chemistry
Organic Chemistry
Authors
Mária PetruÅ¡ová, Michal Vojtech, Božena Pribulová, Erika Lattová, Mária Matulová, Monika Poláková, James N. BeMiller, VladimÃr KÅen, Ladislav PetruÅ¡,