Synonyms: Benzoicacid, 2-[[1,8-dihydroxy-7-[(4-nitrophenyl)azo]-3,6-disulfo-2-naphthalenyl]azo]-(9CI); Benzoic acid,o-[[1,8-dihydroxy-7-[(p-nitrophenyl)azo]-3,6-disulfo-2-naphthyl]azo]- (8CI);2-[(o-Carboxyphenyl)azo]-1,8-dihydroxy-7-[(p-nitrophenyl)azo]-3,6-naphthalenedisulfonicacid; Carboxynitrazo; Carboxynitrazo reagent; Carboxynitroazo