XANTHONE AND FLAVONOL CONSTITUENTS OF SWERTIA HOOKERI

Article abstract of DOI:10.1016/0031-9422(80)85027-8

The whole plant of Swertia hookeri, collected at flowering has been shown to contain two tri- and nine tetraoxygenated free, glucosyloxy, and stearyl ester xanthones and one flavonol stearyl ester.Among these, three are previously unreported in nature and one was known previously only as a synthetic compound.The xanthones are based on 1,3,5-, 1,3,5,8- and 1,3,7,8-oxygenated systems with the middle oxygenation pattern predominating.The two ester compounds appeared only at the flowering stage.Plants collected at the pre-flowering stage gave the corresponding free compounds.The biochemical and biological significance of these findings are appraised.Key Word Index - Swertia hookeri; Gentianaceae; 1-O-stearyl-3,5-dimethoxyxanthone; 3-O-stearyl-3',4',5,7-tetra-O-methylquercetin; 1-hydroxy-3,5-dimethoxyxanthone; tetraoxygenated xanthones; 8-O-β-D-glucosyl-1,3-dihydroxy-5-methoxyxanthones; 8-O-β-D-glucosyl-1,5-dihydroxy-3-methoxyxanthone.