3-hydroxy-4-phenylazo-[2]naphthoic acid
2-hydroxy-naphthalene-1-sulfonic acid
β-naphthol
4-(4-Diethylamino-phenylazo)-3-hydroxy-5-nitro-naphthalene-2-carboxylic acid (4-methoxy-phenyl)-amide
3-Hydroxy-4-(4-methoxy-phenylazo)-5-nitro-naphthalene-2-carboxylic acid (4-methoxy-phenyl)-amide