Flavonoids from the flowers of Nymphaea alba L.

Ten flavonoids were obtained from the flowers of Nymphaea alba L. Their structures were determined mainly on the basis of spectral analyses (UV, 'H NMR, MS). The following aglycons were isolated: quercetin, kaempferol, isokaempferide and apigenin as well as the following glycosides: quercetion 4'-β-xyloside, 3-methylquercetin 3'-β-xyloside and a mixture of quercetin 3-galactoside and 3-glucoside. The structures of three compounds obtained in very small amounts were determined in part.