3-Oxo-N′,2-diphenyl-2,3-di­hydro-1H-pyrazole-4-carbohydrazide

In the title compound, C₁₆H₁₄N₄O₂, the pyrazole ring makes a dihedral angle of 10.49 (8)° with its N-bound phenyl group, while it is nearly perpendicular to the other phenyl ring [dihedral angle = 88.47 (5)°]. The mol­ecular conformation is stabilized by intra­molecular C—H...O and N—H...O hydrogen bonds. In the crystal, the packing involves sheets of mol­ecules parallel to (100) linked by N—H...O hydrogen bonds. A C—H...O interaction is also observed.

Crystal structure of ethyl 2-({[(4Z)-3,5-dioxo-1-phenyl­pyrazolidin-4-yl­idene]meth­yl}amino)­acetate

The title compound, C₁₄H₁₅N₃O₄, is nearly planar, the dihedral angle between the planes of the phenyl and pyrazolidine rings being 1.13 (7) Å, and that between the plane of the pyrazolidine ring and the mean plane of the side chain [C—N—C–C(=O)—O; r.m.s. deviation = 0.024 Å] being 2.52 (7)°. This is due in large part to the presence of the intra­molecular N—H...O and C—H...O hydrogen bonds. In the crystal, pairwise N—H...O hydrogen bonds form inversion dimers, which are further associated into layers, lying very close to plane (-120), via pairwise C—H...O hydrogen bonds. The layers are then weakly connected through C—H...O hydrogen bonds, forming a three-dimensional structure.