RENEWED STUDIES ON THE STRUCTURE OF DIDYMIC ACID

Abstract

The structure (Ia) of didymic acid proposed on the basis of classical experiments has been reexamined by modern methods. The methyl ester of a controlled oxidation product of methyl O-methyldidymate was studied by X-ray crystallographical analysis to revise the earlier structural formula (III) for this compound to (IV). The allocation of n-C₅H₁₁, COOH and OH on the dibenzofuran ring has been established to confirm the structure (Ia).