142689-08-5 1H-2-Benzopyran-7-carboxylic acid, 3,4-dihydro-5-bromo-6,8-dihydroxy-3,4-dimethyl- 3,4-Dihydro-5-bromo-6,8-dihydroxy-3,4-dimethyl-1H-2-benzopyran-7-carboxylic acid