4-(alpha-(p-(diethylamino)phenyl)-(2,5-disulfobenzylidene)-2,5-cyclohexadien-1-ylidene)diethylammonium hydroxide inner salt, sodium salt
N-[4-[4-(diethylamino)phenyl] (2,5-disulfophenyl) Methylene]-2,5-cyclohexadien-1-ylidene]-N-ethylethanaminium hydroxide