Four New Flavonol Glycosides from the Leaves of Brugmansia suaveolens

Four new flavonol glycosides were isolated from the leaves of Brugmansia suaveolens: kaempferol 3-O-β-d-glucopyranosyl-(1'''→2'')-O-α-L-arabinopyranoside (1), kaempferol 3-O-β-d-glucopyranosyl-(1'''→2'')-O-α-L-arabinopyranoside-7-O-į-d-gluco-pyranoside (2), kaempferol 3-O-β-d-[6'''-O-(E-caffeoyl)]-glucopyranosyl-(1'''→2'')-O-α-l-arabinopyranoside-7-O-β-d-glucopyranoside (3), and kaempferol 3-O-β-d-[2'''-O-(E-caffeoyl)]-glucopyranosyl-(1'''→2'')-O-α-l-arabinopyranoside-7-O-β-d-glucopyranoside (4). The structure elucidation was performed by MS, 1D and 2D NMR analyses.