FLAVONE GLYCOSIDES IN THE RAY FLOWERS OF COSMOS BIPINNATUS

Abstract

The ray flowers of Cosmos bipinnatus were found to contain two unknown flavone glycosides. The crystalline pigments were obtained from the methanol extract of the air-dried ray flowers by applying paper chromatography and subsequent recrystallization until to show constant melting points. The one crystalline compound was shown to be chrysoeriol (5,7,4'-trihydroxy–3' -methoxy-flavone)–7–O–glucuronide and the other pigment was proved to be identical with luteolin (5,7,3', 4'-tetrahydroxyflavone)–7–O–glucuronide, which were confirmed by cochromatography, colour reactions and spectral analysis.