Flavonal glycosides from Asperula arvensis L.

Abstract

From the aerial parts of Asperula arvensis L. 9 known flavonol glycosides, namely quercetin (1), isoquercitrin [= quercetin 3-O-b-glucopyranoside] (2), hyperin [= quercetin 3-O-$beta$ -galactopyranoside] (3), quercetin 7-O-$beta$-galactopyranoside (4), quercetin 4'-O-$beta$-galactopyranoside (5), isorhamnetin 3-O-$beta$ -galactopyranoside (6), isorhamnetin 5-O-$beta$-galactopyranoside (7), dihydrokaempferol 7-4'-dimethylether 3-O-$beta$ -glucopyranoside (8) and isorhamnetin 3-O-$alpha$ -rhamnopyranosyl $(1''' rightarrow 6'')-beta$ -glucopyranosid (9), were isolated. The structures of the compounds were elucidated by high field 1D and 2D NMR and ESI-MS spectroscopies.