Synonyms: 7-Benzothiazolesulfonicacid,2-[4-[[4,5-dihydro-1-(hydroxymethyl)-3-methyl-5-oxo-1H-pyrazol-4-yl]azo]phenyl]-6-methyl-,monosodium salt (9CI); 7-Benzothiazolesulfonic acid,2-[p-[[1-(hydroxymethyl)-3-methyl-5-oxo-2-pyrazolin-4-yl]azo]phenyl]-6-methyl-,monosodium salt (8CI); 7-Benzothiazolesulfonic acid,2-[4-[[1-(hydroxymethyl)-4,5-dihydro-3-methyl-5-oxo-1H-pyrazol-4-yl]azo]phenyl]-6-methyl-,monosodium salt