Syntheses, Characterization, Crystal Structures and Xanthine Oxidase Inhibitory Activity of Hydrazones

Four new fluoro-containing hydrazones were synthesized from 4-fluorobenzaldehyde with chloro- and nitro-substituted benzohydrazides. They are 3-chloro-N'-(4-fluorobenzylidene)benzohydrazide (1), 2-chloro-N'-(4-fluorobenzylidene) benzohydrazide (2), N'-(4-fluorobenzylidene)-4-nitrobenzohydrazide (3), and N'-(4-fluorobenzylidene)-3-nitrobenzohydrazide (4). The compounds have been characterized by IR and 1H NMR spectroscopy, as well as X-ray single crystal determination. Xanthine oxidase (XO) inhibitory activity indicated that the nitro substituted compounds 3 and 4 have effective activity. Docking simulation was performed to insert the compounds into the crystal structure of xanthine oxidase at the active site to investigate the probable binding modes.