Synonyms: 1H-Pyrazole-3-carboxylicacid, 4,5-dihydro-5-oxo-4-[(4-sulfo-1-naphthalenyl)azo]-1-(4-sulfophenyl)-,3-ethyl ester, disodium salt (9CI); 2-Pyrazoline-3-carboxylic acid,5-oxo-4-[(4-sulfo-1-naphthyl)azo]-1-(p-sulfophenyl)-, 3-ethyl ester, disodiumsalt (8CI); C.I. Acid Orange 137; Orange B