4-Chloro-benzaldehyde (1-isobutyl-1H-imidazo[4,5-c]quinolin-4-yl)hydrazone monohydrate.

In the title compound, C(21)H(20)ClN(5)·H(2)O, the 1H-imidazo[4,5-c]quinoline ring is approximately planar, with a maximum deviation of 0.0795 (7) Å, and it forms a dihedral angle of 7.65 (3)° with the chloro-phenyl ring. In the crystal, the components are linked into chains along the a axis via inter-molecular N-H⋯O, O-H⋯N and C-H⋯O hydrogen bonds. One of the H atoms of the water mol-ecule is disordered over two positions with a site-occupancy ratio of 0.80 (4):0.20 (4).