[4-[bis[3-(carboxymethyl)-4-ethoxyphenyl]methylene]-2,5-cyclohexadien-1-ylidene]dimethylammonium

N-[4-[(3-Carboxylatomethyl-4-ethoxyphenyl)(3-carboxymethyl-4-ethoxyphenyl)methylene]-2,5-cyclohexadien-1-ylidene]-N-methylmethanaminium