5-((4,5-Dihydro-3-methyl-5-oxo-1-(4-((2-(sulphooxy)ethyl)sulphonyl)phenyl)-1H-pyrazol-4-yl)azo)-2,4-dimethoxybenzenesulphonic acid 58779-19-4 Benzenesulfonic acid, 5-((4,5-dihydro-3-methyl-5-oxo-1-(4-((2-(sulfooxy)ethyl)sulfonyl)phenyl)-1H-pyrazol-4-yl)azo)-2,4-dimethoxy- EINECS 261-438-8