Abstract
The interglycosidic linkages of four quinovic acid glycosides previously described from the bark of Nauclea diderrichii (de Wild) Merr. (Rubiaceae) are revised on the basis of 2D-NMR spectroscopic results. The structures were established as: quinovic acid 3-O-β-glucopyranosyl(1→4)-β-fucopyranosyl-(28→1)-β -glucopyranosyl ester, quinovic acid 3-O-β-glucopyranosyl-(1→4)-α-rhamnopyranosyl-(28→1)-β-glucopyranosyl ester, quinovic acid 3-O-β-glucopyrnaosyl-(1→4,)-β-fucopyranoside, and quinovic acid 3-O-β-glucopyranosyl-(1→4)-α-rhamnopyranoside. The first three saponins are new compounds.
