1887-02-1 2,5-Cyclohexadiene-1,4-dione, 2,3,5,6-tetrahydroxy-, disodium salt HPEK 1 Kelox M 122 NCI 974 NSC33520 THQ Tetrahydroxyquinone disodium derivative Tetrahydroxyquinone, disodium salt Tetroquinone disodium derivative p-Benzoquinone, 2,3,5,6-tetrahydroxy-, disodium salt p-Benzoquinone, tetrahydroxy-, disodium deriv.