13C-NMR Data of Tetraoxygenated Xanthones from Centaurium pulchellum Druce.

Three tetraoxygenated xanthones have been isolated from Centaurium pulchellum namely 1,8-dihydroxy 3,5-dimethoxy xanthone 1, I, 8-dihydroxy 3, 7-dimethoxy xanthone 2 and I-hydroxy 3, 7, 8-trimethoxy xanthone 3, respectively. As the 13C-NMR data of these xanthones have not been reported earlier, we measured and multiplicity assignments made using polarization transfer pulse sequences (DEPT) and HMQC. 

H BIBI ,I ALI ,M I CHOUDHARY ,G A MIANA ,