title: Direct synthesis of C-glycosides from unprotected 2-N-acyl-aldohexoses via aldol condensation-oxa-Michael reactions with unactivated ketones.
abstract: C-glycosides are important compounds as they are used as bioactive molecules and building blocks. We have developed methods to concisely synthesize C-glycosides from unprotected 2-N-acyl-aldohexoses and unactivated ketones; we designed aldol-condensation-oxa-Michael addition reactions catalyzed by amine-based catalysts using additives. Depending on the conditions used, C-glycosides were stereoselectively obtained. Our methods allowed the C-C bond formations at the anomeric centers of unprotected carbohydrates under mild conditions to lead the C-glycosides in atom- and step-economical ways.
authors.affiliation: Chemistry and Chemical Bioengineering Unit, Okinawa Institute of Science and Technology Graduate University, 1919-1 Tancha, Onna, Okinawa 904-0495, Japan. ftanaka@oist.jp.
authors.forename: Sherida
authors.initials: S
authors.lastname: Johnson
authors.forename: Fujie
authors.initials: F
authors.lastname: Tanaka
mesh_terms: D000447:Aldehydes / Q000737:chemistry*; D006027:Glycosides; D006601:Hexoses / Q000737:chemistry*; D007659:Ketones / Q000737:chemistry*; D008968:Molecular Conformation; D009005:Monosaccharides / Q000138:chemical synthesis* / Q000737:chemistry; D013237:Stereoisomerism
chemical_list: D000447:Aldehydes; C438934:C-glycoside; D006027:Glycosides; D006601:Hexoses; D007659:Ketones; D009005:Monosaccharides; C116609:3-hydroxybutanal