N′-[(2Z)-4-Oxo-4-phenyl­but-2-en-2-yl]pyridine-4-carbohydrazide

There are significant twists in the title compound, C₁₆H₁₅N₃O₂, as seen in the dihedral angle between the benzene and adjacent but-2-enal group [29.26 (4)°] and between the pyridine ring and amide group [24.79 (6)°]. A twist is also evident around the hydrazine bond [the C—N—N—C torsion angle is −138.25 (13)°]. The conformation about the ethene bond is Z. An intra­molecular N—H...O hydrogen bond involving the benzoyl O atom and leading to an S(6) motif is formed. Significant delocalization of π-electron density is found in this part of the mol­ecule. In the crystal, helical supra­molecular chains aligned along the b axis and mediated by N—H...O hydrogen bonds are formed.