(1-methylethylidene)di-4,1-phenylene bis(6-diazo-5,6-dihydro-5-oxonaphthalene-1-sulphonate)

Bis(6-diazo-5,6-dihydro-5-oxo-1-naphthalenesulfonic acid)propane-2,2-diylbis(4,1-phenylene) ester