European Journal of Chemistry 2022, 13(3), 307-318 | doi: | Get rights and content

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iNOS inhibitors: Benzimidazole-coumarin derivatives to combat inflammation

Richa Minhas (1) orcid , Yogita Bansal (2,*) orcid

(1) Department of Pharmaceutical Sciences and Drug Research, Punjabi University, Patiala - 147002 India
(2) Department of Pharmaceutical Sciences and Drug Research, Punjabi University, Patiala - 147002 India
(*) Corresponding Author

Received: 22 Apr 2022 | Revised: 15 Jun 2022 | Accepted: 19 Jun 2022 | Published: 30 Sep 2022 | Issue Date: September 2022


Inducible nitric oxide synthase (iNOS) plays an important role in the inflammatory processes via accelerating the production of nitric oxide (NO). The efforts to develop small molecules as selective inhibitors of iNOS are being reported across the globe. The current study explores varied benzimidazole-coumarin derivatives as anti-iNOS agents. Literature survey suggests 2-aminobenzimidazole, coumarin nucleus, and 4-atom linker as important structural components for iNOS inhibition. Target compounds were designed and synthesized by coupling 2-aminobenzimidazole with (un)substituted coumarin through different linkers. These were docked in iNOS (1QW4) and nNOS (1QW6) targets to ascertain their iNOS selectivity, and evaluated for NO and iNOS inhibitory activities in vitro. The most active inhibitors were subsequently evaluated for acute toxicity and anti-inflammatory activity using carrageenan-induced rat paw edema model in vivo. All compounds possessed moderate to good NO and iNOS inhibitory activities. Compounds 14a, 14b, 14d, and 14e were the most potent inhibitors in vitro. These were found to significantly reduce the inflammation. Compounds 14d and 14e have been identified as the most potent iNOS inhibitors to combat inflammation. These derivatives may serve as potential compounds as such against iNOS, or as leads for the development of novel anti-iNOS agents.


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European Journal of Chemistry


Docking; Coumarin; Carrageenan; Inflammation; Benzimidazole; Biological activity

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DOI: 10.5155/eurjchem.13.3.307-318.2282

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Department of Science and Technology, Ministry of Science and Technology, India.


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How to cite

Minhas, R.; Bansal, Y. Eur. J. Chem. 2022, 13(3), 307-318. doi:10.5155/eurjchem.13.3.307-318.2282
Minhas, R.; Bansal, Y. iNOS inhibitors: Benzimidazole-coumarin derivatives to combat inflammation. Eur. J. Chem. 2022, 13(3), 307-318. doi:10.5155/eurjchem.13.3.307-318.2282
Minhas, R., & Bansal, Y. (2022). iNOS inhibitors: Benzimidazole-coumarin derivatives to combat inflammation. European Journal of Chemistry, 13(3), 307-318. doi:10.5155/eurjchem.13.3.307-318.2282
Minhas, Richa, & Yogita Bansal. "iNOS inhibitors: Benzimidazole-coumarin derivatives to combat inflammation." European Journal of Chemistry [Online], 13.3 (2022): 307-318. Web. 30 May. 2023
Minhas, Richa, AND Bansal, Yogita. "iNOS inhibitors: Benzimidazole-coumarin derivatives to combat inflammation" European Journal of Chemistry [Online], Volume 13 Number 3 (30 September 2022)

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