2-Naphthalenecarboxylic acid, 4-((2,3-dichlorophenyl)azo)-3-hydroxy- 4-((2,3-Dichlorophenyl)azo)-3-hydroxy-2-naphthalenecarboxylic acid 4-((2,3-Dichlorophenyl)azo)-3-hydroxy-2-naphthoic acid 72121-71-2 EINECS 276-351-0