Crystal structure, Hirshfeld surface analysis and HOMO-LUMO analysis of (E)-N'-(3-hy-droxy-4-meth-oxy-benzyl-idene)nicotinohydrazide monohydrate.

The mol-ecule of the title Schiff base compound, C14H13N3O3·H2O, displays a trans configuration with respect to the C=N bond. The dihedral angle between the benzene and pyridine rings is 29.63 (7)°. The crystal structure features inter-molecular N-H⋯O, C-H⋯O, O-H⋯O and O-H⋯N hydrogen-bonding inter-actions, leading to the formation of a supramolecular framework. A Hirshfeld surface analysis indicates that the most important contributions to the crystal packing are from H⋯H (37.0%), O⋯H/H⋯O (23.7%)), C⋯H/H⋯C (17.6%) and N⋯H/H⋯N (11.9%) inter-actions. The title compound has also been characterized by frontier mol-ecular orbital analysis.

Crystal structure, Hirshfeld surface analysis and HOMO-LUMO analysis of (E)-4-bromo-N'-(4-meth-oxy-benzyl-idene)benzohydrazide.

The title Schiff base compound, C15H13BrN2O2, displays an E configuration with respect to the C=N double bond, which forms a dihedral angle of 58.06 (9)° with the benzene ring. In the crystal, the mol-ecules are linked into chains parallel to the b axis by N-H⋯O and C-H⋯O hydrogen bonds, giving rise to rings with an R 2 1(6) graph-set motif. The chains are further linked into a three-dimensional network by C-H⋯π inter-actions. A Hirshfeld surface analysis indicates that the most important contributions to the crystal packing are from C⋯H (33.2%), H⋯H (27.7%), Br⋯H/H⋯Br (14.2%) and O⋯H/H⋯O (13.6%) inter-actions. The title compound has also been characterized by frontier mol-ecular orbital analysis.