NEW p-AMINODIPHENYLAMINE AMIDE COMPOUNDS: DESIGN, SYNTHESIS AND ANTI β-lACTAMASES ACTIVITY EVALUATION

Abstract

β-Lactams, such as penicillins and cephalosporins, have long been recognized as the most effective antibiotics for the treatment of infectious diseases. However, the major limitation to their effectiveness is the bacterial production of β-lactamase enzymes, which hydrolyze the β-lactam ring in these drugs, rendering them inactive. To overcome this resistance mechanism, β-lactamase inhibitors, such as clavulanic acid, are commonly used in combination with β-lactams. By inhibiting the action of β-lactamase enzymes, these inhibitors restore the efficacy of β-lactam antibiotics. In recent studies, researchers have employed docking techniques to investigate the interaction between β-lactamase enzymes and potential inhibitors. Specifically, the β-lactamases TEM-1 (1pzp) and IMP-1 (1JJE) were used as targets for designing new compounds. A series of novel compounds were generated by synthesizing 6 amides compounds as acid chloride derivatives and reacting them with p-aminodiphenylamine to form amide bonds. These compounds were then characterized by the use of various physical and spectroscopic methods to confirm their structures. Next, the synthesized compounds were subjected to biological testing to evaluate their efficacy against β-lactamaseproducing Gram-positive and Gram-negative bacteria. This was accomplished by determining the minimum inhibitory concentration (MIC) of the compounds against three different strains of bacteria. Additionally, the possible anti β-lactamase activities of the compounds were compared to that of clavulanic acid. The results of this study revealed that five of the synthesized products exhibited effect similar to that of clavulanic acid for only one bacterial strain (Staph. aureus). Furthermore, the findings of the docking study suggest that the β-lactamase active pocket has a preference for hydrophobic substituents, as the synthesized products with these groups showed the highest binding score. In conclusion, the use of β-lactamase inhibitors, such as clavulanic acid, in combination with β-lactam antibiotics has proven effective in combating bacterial resistance. The development of novel compounds with anti β-lactamase activity holds promise for improving the treatment of infectious diseases. By understanding the preferences of the β-lactamase active pocket and designing compounds with hydrophobic substituents, researchers can enhance the affinity and efficacy of these inhibitors. This research contributes to the ongoing efforts to combat antibiotic resistance and improve patient outcomes in the field of infectious disease treatment.