Two new flavonol glycosides from the Tibetan medicinal plant Aconitum tanguticum.

Abstract

Two new flavonol glycosides characterized as quercetin 3-O-α-l-rhamnopyranosyl-(1 → 2)-[β-d-glucopyranosyl-(1 → 3)-α-l-(4-O-trans-p-coumaroylrhamnopyranosyl)-(1 → 6)]-β-d-galactopyranoside-7-O-α-l-rhamnopyranoside (1) and kaempferol 3-O-α-l-rhamnopyranosyl-(1 → 2)-[β-d-glucopyranosyl-(1 → 3)-α-l-(4-O-trans-p-coumaroyl rhamnopyranosyl)-(1 → 6)]-β-d-galactopyranoside-7-O-α-l-rhamnopyranoside (2), together with two known flavonol glycosides quercetin 3-O-α-l-rhamnopyranosyl-(1 → 2)- [α-l-rhamnopyranosyl-(1 → 6)]-β-d-galactopyranoside-7-O-α-l-rhamnopyranoside (3) and kaempferol 3-O-α-l-rhamnopyranosyl-(1 → 2)-[α-l-rhamnopyranosyl-(1 → 6)]-β-d-galactopyranoside-7-O-α-l-rhamnopyranoside (4), were isolated from the whole plant of Aconitum tanguticum (Maxim.) Stapf. The structures of the new compounds were elucidated by spectroscopic methods, and the total (1)H and (13)C NMR chemical shifts were assigned.