Flavonoid glycosides and their p-coumaroyl esters from Campylospermum calanthum leaves.

Six new compounds, comprising three flavonoid glycosides and their respective coumaroyl esters, have been isolated and characterized from the methanol extract of the leaves of Campylospermum calanthum, along with three known flavonoid aglycones, 7-O-methyl apigenin (1), 7-O-methyl luteolin (2), and 7-O-methyl quercetin (3). Their structures were elucidated based on chemical evidence as well as spectroscopic analysis including 1D and 2D NMR (1H-1H COSY, HSQC, HMBC, and NOESY) spectroscopy and by comparing their spectral data with those reported for related compounds.