Synthesis of quercetin 3- O-β- d-apiofuranosyl-(1→2)-[α- l-rhamnopyranosyl-(1→6)]-β- d-glucopyranoside

Abstract

A concise method to construct a unique 2,6-branched trisaccharide was established by regioselective glycosylation of three free hydroxyl groups on a 3- O-protected glucose moiety, and successfully used in the synthesis of quercetin 3- O-β- d-apiofuranosyl-(1→2)-[α- l-rhamnopyranosyl-(1→6)]-β- d-glucopyranoside, a flavonol O-glycoside isolated from glandless cotton seeds which showed notable antidepressant activities.