2,6,2',6'-tetramethyldiphenoquinone, 3,3',5,5'-Tetramethyldiphenoquinone, 3,3',5,5'-tetramethyl-1,1'-bi(cyclohexa-2,5-dien-1-ylidene)-4,4'-dione, 3,3',5,5'-Tetramethyl-4,4'-diphenoquinone, 3,3',5,5'-tetramethyl-1,4-diphenoquinone, 2,5-Cyclohexadien-1-one,4-(3,5-dimethyl-4-oxo-2,5-cyclohexadien-1-ylidene)-2,6-dimethyl, 3,5,3',5'-tetramethyl-4,4'-diphenoquinone, (Bi-2,5-cyclohexadien-1-ylidene)-4,4'-dione,3,3',5,5'-tetramethyl, Tetramethyldiphenoquinone, 4-(3,5-dimethyl-4-oxo-2,5-cyclohexadienylidene)-2,6-dimethyl-2,5-cyclohexadienone