Development of Pyrazole Derivatives as Xanthine Oxidase Inhibitors

A series of arylhydrazono pyrazoles and aryldiazenyl pyrazoles were prepared by rapid one-pot microwave assisted synthesis. In this method, the synthesis of these pyrazoles was carried out by reacting ethyl acetoacetate/acetylacetone, isoniazid, and aryldiazonium salts under solvent free conditions. All the synthesized compounds were fully characterized by infrared, nuclear magnetic resonance, and mass spectrometry. In vitro xanthine oxidase (XO) inhibitory studies revealed that the presence of bromo group at the phenyl ring had significant XO inhibitory activity.