STRUCTURE OF FISTULIC ACID – A NEW COLOURING MATTER FROM THE PODS OF CASSIA FISTULA

Abstract

Chemical examination of the pods of Cassia fistula Linn, has led to the isolation of a new anthraquinone, provisionally named as fistulic acid, from the alcoholic extract. From the studies based on the elemental analysis, I.R. and UV spectra, acetylation, colour reactions, zinc–dust distillation, bromination, oxidation with alkaline potassium permanganate and caustic potash fusion, the structure of fistulic acid has been tentatively assigned to be 1,4–dihydroxy–6,7–dimethoxy–2–methylanthraquinone–3–carboxylic acid.