4-[(2-chloro-4-nitrophenyl)azo]-2,4-dihydro-5-methyl-2-(tetrahydro-3-thienyl)-3H-pyrazol-3-one S,S-dioxide

3-[[4-[(2-Chloro-4-nitrophenyl)azo]-3,4-dihydro-5-methyl-3-oxo-2H-pyrazol]-2-yl]tetrahydrothiophene 1,1-dioxide

3H-Pyrazol-3-one, 4-[(2-chloro-4-nitrophenyl) azo]-2,4-dihydro-5-methyl-2-(tetrahydro-3-thienyl )-, S,S-dioxide