Synonyms: Copper(1+), (5'-(2-(3-(4,5-dihydro-4-(2-(2-(hydroxy-kappaO)-5-nitrophenyl)diazenyl-kappaN1)-3-methyl-5-(oxo-kappaO)-1H-pyrazol-1-yl)phenyl)diazenyl)-1'-(3-(dimethylamino)propyl)-1',2'-dihydro-6'-hydroxy-4'-methyl-2'-oxo-1,3'-bipyridiniumato(2-))-, 2-hydroxypropanoate (1:2);Copper(1+), (5'-((3-(4,5-dihydro-4-((2-hydroxy-5-nitrophenyl)azo)-3-methyl-5-oxo-1H-pyrazol-1-yl)phenyl)azo)-1'-(3-(dimethylamino)propyl)-1',2'-dihydro-6'-hydroxy-4'-methyl-2'-oxo-1,3'-bipyridiniumato(2-))-, salt with 2-hydroxypropanoic acid (1:2)