71873-49-9 Benzoic acid, 4,4'-(1,2-ethenediylbis((3-sulfo-4,1-phenylene)-ONN-azoxy-4,1-phenyleneazo))bis-, tetrasodium salt EINECS 276-125-1 Tetrasodium p,p'-(vinylenebis((3-sulphonato-p-phenylene)-ONN-azoxy-p-phenyleneazo))dibenzoate