Syntheses, Crystal Structures and Xanthine Oxidase Inhibitory Activity of Aroylhydrazones

A series of hydrazones, (E)-N'-(4-hydroxy-3-methoxybenzylidene)-4-nitrobenzohydrazide (1), (E)-4-(dimethylamino)-N'-(4-hydroxy-3-methoxybenzylidene)benzohydrazide (2), N'-(2-hydroxy-5-methylbenzylidene)-4-nitrobenzohydrazide (3) and 2-fluoro-N'-(2-hydroxy-5-methylbenzylidene)benzohydrazide (4), were prepared and structurally characterized by elemental analysis, IR and 1H NMR spectra, and X-ray single crystal determination. The xanthine oxidase inhibitory activities of the compounds were investigated. Among the compounds, N'-(3-methoxybenzylidene)-4-nitrobenzohydrazide (1) showed the strongest activity. Docking simulations were performed to insert the compounds into the crystal structure of xanthine oxidase at the active site and to investigate the probable binding modes.