1,5-cyclohexadiene-1-carboxylic acid, 3-bromo-3,5-bis(1,1-dimethylethyl)-4-oxo- 3-bromo-3,5-di-tert-butyl-4-oxocyclohexa-1,5-diene-1-carboxylic acid InChI=1/C15H21BrO3/c1-13(2,3)10-7-9(12(18)19)8-15(16,11(10)17)14(4,5)6/h7-8H,1-6H3,(H,18,19