Crystal structure of 4-[(E)-(4-hy-droxy-benzyl-idene)amino]-1,5-dimethyl-2-phenyl-1H-pyrazol-3(2H)-one.

The asymmetric unit of the title compound, C18H17N3O2, comprises three independent mol-ecules (1, 2 and 3). In mol-ecule 1, the dihedral angles between the pyrazolone ring and the pendant phenyl and hydroxybenzene rings are 54.43 (6) and 28.72 (6)°, respectively. The corresponding data for mol-ecule 2 are 86.84 (6) and 25.69 (5)°, respectively, and for mol-ecule 3 are 47.41 (7) and 17.09 (7)°, respectively. The three mol-ecules feature an intra-molecular C-H⋯O inter-action, which closes an S(6) ring in each case. In the crystal, mol-ecules are linked by O-H⋯O hydrogen bonds, which generate [100] chains incorporating all three asymmetric mol-ecules. Two weak C-H⋯O interactions connect three independent molecules to each other along the c-axis direction.