Extractives from Guttiferae. Part XII. The isolation and structure of seven xanthones from Calophyllum fragrans Ridley

Abstract

Six xanthones: euxanthone, buchanaxanthone, 1,5,6-trihydroxyxanthone, 6-desoxyjacareubin, jacareubin, and 2-(3,3-dimethylallyl)-1,3,5,6-tetrahydroxyxanthone, have been isolated from the heartwood of Calophyllum fragrans Ridley. By methylation of the crude extracts, 8-hydroxy-1,2-dimethoxyxanthone has been isolated and 1,3,5,6- and 1,3,6,7-tetramethoxyxanthones were detected by t.l.c.