Oxidation studies on Andrographolide.

Jones oxidation of Andrographolide (1), gave mixture of three products (3-dehydroandrographolide (5), 3,19-bis dehydroandrographolide (6) and 19-dehydroandrographolide (7). Tritylation of andrographolide at C19-OH resulted to products 8 and diene 9, which can be converted to its acetate 10 and oxidation product 11.