(E)-N'-(4-Pyridylmethyl-ene)-4-(8-quinol-yl-oxy)butanohydrazide 0.25-hydrate.

The asymmetric unit of the title compound, C(19)H(18)N(4)O(2)·0.25H(2)O, contains two organic mol-ecules and a solvent water mol-ecule with 50% occupancy. The two molecules differ in their conformations: in one mol-ecule it is (+)gauche-trans-trans-(+)gauche-trans, whereas in the other it is (-)gauche-trans-trans-(-)gauche-trans. The dihedral angles between the pyridine ring and the quinoline ring system are 67.4 (3) and 68.0 (2)°. Mol-ecules are linked into a supra-molecular two-dimensional array via N-H⋯N hydrogen bonds, with each partially occupied water mol-ecule connected via an O-H⋯O hydrogen bond. C-H⋯O inter-actions are also present.