Polyphenol components of the knotwood extracts of Salix caprea l .

According to HPLC, NMR spectroscopy, and mass spectrometry, the extracts of the knotwood of Salix capreal. contain catechin (1), 7-O-(β-d-glucopyranosyl)dihydrokaempferol (2), 7-O-(β-d-glucopyranosyl)dihydrokaempferol-4′-O-methyl ether (3), 7-O-(β-d-glucopyranosyl)naringenin (prunin) (4), naringenin (5), and dihydrokaempferide (6). Compound 3 was not described previously.