2-Pyrazolin-5-one,1,3-diphenyl, 3H-Pyrazol-3-one,2,4-dihydro-2,5-diphenyl, 2,5-Diphenyl-2,4-dihydro-pyrazol-3-one, 2,5-Diphenyl-2,4-dihydro-3H-pyrazol-3-one, 1,3-diphenyl-4,5-dihydro-pyrazolin-5-one, 1,3-diphenyl-4,5-dihydropyrazol-5-one, 1,3-diphenyl-1,4-dihydropyrazol-5-one, 1,3-diphenyl-4,5-dihydro-1H-pyrazol-5-one, 1,3-diphenyl-5-oxo-4,5-dihydro-1H-pyrazole