抄録
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).
