90294-90-9 Copper, 4-((4-aminophenyl)azo)benzoic acid-2,2'-(1,2-ethenediyl)bis(5-nitrobenzenesulfonic acid)-4-hydroxy-3-((2-methoxy-4-(methylamino)phenyl)azo)benzenesulfonic acid reaction products sodium complexes EINECS 290-979-2