(E)-3-Amino-4-(2-phenylhydrazinylidene)-1H-pyrazol-5(4H)-one

Abstract

The mol­ecule of the title compound, C9H9N5O, is essentially planar (r.m.s. deviation of all atoms = 0.02 Å) except for the NH2 H atoms. An intra­molecular hydrazinyl­idene–carbonyl N—H⋯O=C hydrogen bond is present. In the crystal, mol­ecules are connected via N—H⋯N/O hydrogen bonds, forming thick layers parallel to (100).