ABSTRACT: Background: The major cause of sickness and death is infectious diseases worldwide. As bacteria develop resistance at a quicker pace, novel antimicrobial compounds with various sites of action and sensitivity to resistant bacteria, as well as safety, are needed as a superior alternative to currently existing treatments. Heterocyclic compounds have long caught the interest of researchers due to their broad spectrum of applications and convenience of modification, dating back to the early days of chemical study. In medicinal chemistry, the benzimidazole molecule is a prominent pharmacophore and preferred structure.
Method: The method described in the literature was used to synthesize benzimidazole and mercapto-benzimidazole utilising microwave irradiation. In the presence of K2CO3, benzimidazole/mercapto-benzimidazole was reacted with 2-chloro-N-substituted acetamide to produce desirable N-substituted-2-substituted benzimidazole derivatives (5a-l). Microwave irradiation speeds up the process and reduces impurities. IR, 1HNMR, 13CNMR and MS is used to confirm the structure of synthesised derivatives.A molecular docking investigation was done on two protein targets, DNA gyrase subunit B (5L3J) and Staphylococcus aureus tyrosyl-tRNA synthetase (1JIJ), using a typical docking technique.
Result: The desired compounds were synthesised with excellent purity and yield by Microwave aided synthesis. 5d, 5e, and 5k have a high yield.The biological activity of derivatives on a given target side can be predicted via a molecular docking research. The docking score indicates that they have a stronger binding contact than the reference ligand. The maximum binding affinity is found in 5c, 5e, and 5k.
Conclusion: According to the findings, compounds 5c, 5d, 5e and 5k show a strong potential for antibacterial action. The potency of benzimidazole derivatives might be improved with more SAR studies.

Keywords—N-substituted benzimidazole, Molecular docking, DNA gyrase, auotodock viva, microwave assisted synthesis

| DOI: 10.17148/IARJSET.2021.8691