4-Chloro-3-(4,5-dihydro-3-methyl-5-oxo-4-(phenylazo)-1H-pyrazol-1-yl)benzenesulphonic acid, compound with butylamine (1:1) 71566-56-8 Benzenesulfonic acid, 4-chloro-3-(4,5-dihydro-3-methyl-5-oxo-4-(phenylazo)-1H-pyrazol-1-yl)-, compd. with 1-butanamine (1:1) EINECS 275-641-4