The 5-Methyl-2-phenyl-1,2-dihydropyrazol-3-one, with the CAS registry number 19735-89-8 and EINECS registry number 243-261-8, has the systematic name of 5-methyl-2-phenyl-1,2-dihydro-3H-pyrazol-3-one. And the molecular formula of the chemical is C₁₀H₁₀N₂O.

The characteristics of this chemical are as followings: (1)ACD/LogP: 1.72; (2)# of Rule of 5 Violations: 0; (3)ACD/LogD (pH 5.5): 1.72; (4)ACD/LogD (pH 7.4): 1.72; (5)ACD/BCF (pH 5.5): 11.86; (6)ACD/BCF (pH 7.4): 11.86; (7)ACD/KOC (pH 5.5): 204.35; (8)ACD/KOC (pH 7.4): 204.36; (9)#H bond acceptors: 3; (10)#H bond donors: 1; (11)#Freely Rotating Bonds: 1; (12)Polar Surface Area: 23.55 Å²; (13)Index of Refraction: 1.586; (14)Molar Refractivity: 49.63 cm³; (15)Molar Volume: 147.7 cm³; (16)Polarizability: 19.67×10^-24cm³; (17)Surface Tension: 42.8 dyne/cm; (18)Density: 1.178 g/cm³; (19)Flash Point: 121 °C; (20)Enthalpy of Vaporization: 51.5 kJ/mol; (21)Boiling Point: 276.4 °C at 760 mmHg; (22)Vapour Pressure: 0.0048 mmHg at 25°C.

Uses of 5-Methyl-2-phenyl-1,2-dihydropyrazol-3-one: It can react with tetrahydrothiophene 1-oxide to produce (2,3-Dihydro-5-methyl-3-oxo-2-phenyl-1H-pyrazol-4-yl)-tetrahydrothiopheniumperchlorat. This reaction will need reagent TFA and aq. LiCLO₄, and the menstruum CH₂Cl₂. And the yield is about 92%.

Addtionally, the following datas could be converted into the molecular structure:
(1)SMILES: O=C2\C=C(/NN2c1ccccc1)C
(2)InChI: InChI=1/C10H10N2O/c1-8-7-10(13)12(11-8)9-5-3-2-4-6-9/h2-7,11H,1H3
(3)InChIKey: KZQYIMCESJLPQH-UHFFFAOYAA