Preparation, Characterization, Anti-Bacterial Activity and Anti-Oxidation Activity for Some New Benzodioxolyl Pyrazoline Derivatives

In this work, a series of new benzodioxolyl pyrazoline derivatives (a6-10) has been synthesized successfully. Some of the different aromatic aldehydes have been added to benzodioxolyl keto compound in strong alkaline media to produce chalcones (a1-5). These chalcones were been converted to pyrazoline through cyclization reaction using phenyl hydrazine as cyclization agent. The structures of the prepared compounds have been proved in terms of the structure characterization depending on the spectral data, using spectroscopy techniques such as Fourier Transform Infrared (FTIR), Proton Nuclear Magnetic Resonance (1HNMR) and Carbon Nuclear Magnetic Resonance 13CNMR. In addition to using of Gas Chromatography Mass Spectroscopy (GC mass) for the final series of the new pyrazole derivatives to verify their structures. These synthesized compounds have been screened for their antibacterial activity effect evaluation towards Staphylococcus aureus and Staphylococcus epidermidis (Gram-positive bacteria) and Escherichia coli and Pseudomonas aeruginosa (Gram-negative bacteria). Additionally, the Free Radical Scavenging Activity (RSA) of the synthesized pyrazoline (a6-10) has been assessed using the 2,2-diphenyl-1-picrylhydrazyl (DPPH) as antioxidant. The results indicated lack of the antibacterial and antioxidant activity effect. For the antibacterial activity effect results, it could be related to penetrate of bacterial cellular targets insufficiently and the absence of active centers in pyrazoline structure for binding to bacteria’s outer cell sufficiently. In the case of antioxidant test, one of the reasons is could be the absence of some good electron-releasing substituents such hydroxy (OH), amine (NH) and thiol (SH) having the ability to donate hydrogen atoms or electrons efficiently to neutralize free radicals. These pyrazoline derivatives don’t behave as active biomaterial characteristics against the tested bacteria for both antibacterial and antioxidant activity effect.