1-Phenyl-3-methyl-5-pyrazolone 1-Phenyl-3-methylpyrazolone 2-Pyrazolin-5-one, 3-methyl-1-phenyl- 3-Methyl-1-phenyl-2-pyrazolin-5-one 3-Methyl-1-phenyl-5-pyrazolone 3H-Pyrazol-3-one, 2,4-dihydro-5-methyl-2-phenyl-