In-Vitro Antibacterial and Antifungal Evaluation of 2-Mercaptobenzimidazole Mannich Based Derivatives:Structure Activity Relationship and MIC Analysis against clinically relevant pathogens

Authors

  • Hafiz Aamir Ali Kharl Riphah Institute of Pharmaceutical Sciences, Riphah International University, Islamabad, Pakistan. Department of Pharmacy, Quaid-i-Azam University, Islamabad, Pakistan
  • Abida Shamim Department of Pharmacy, Ibadat International University, Islamabad, Pakistan. Department of Pharmacy, Quaid-i-Azam University, Islamabad, Pakistan
  • Muhammad Akmal Farooq Department of Pharmacy, Faculty of Health & Pharmaceutical Sciences, University of Agriculture, Faisalabad, Pakistan
  • Aneela Tahir Riphah Institute of Pharmaceutical Sciences, Riphah International University, Islamabad, Pakistan
  • Saqib Khan Department of Pharmacy, University of Swabi, Khyber Pakhtunkhwa, Pakistan. College of Pharmacy, HBS Institute of Healthcare and Allied Health Sciences, Islamabad, Pakistan
  • Samreen Khan Department of Pharmacy, Ibadat International University, Islamabad, Pakistan. Faculty of Pharmacy, Capital University of Science & Technology, Islamabad, Pakistan
  • Sohaib Iqbal College of Pharmacy, Lyallpur Institute of Advanced Studies, Faisalabad, Pakistan
  • Maaz Khan Department of Pharmacy, Ibadat International University, Islamabad, Pakistan
  • Syed Muzammil Masaud Department of Allied Health Sciences, The Saifee Burhani University, Karachi, Pakistan
  • Muhammad Moaaz Ali Department of Pharmacology, NUST School of Health Sciences, Islamabad, Pakistan

DOI:

https://doi.org/10.70749/ijbr.v4i2.2892

Keywords:

Multidrug-resistant, Mannich derivatives, Gram-positive, Gram-negative, Structure activity relationship, Good Health & Well being

Abstract

The appearance of multi-drug resistant microbial pathogens requires the need for developing new antimicrobial agents with enhanced efficacy and spectrum. In the current research work, a set of 2-mercaptobenzimidazole Mannich bases was synthesized and tested for their antibacterial and antifungal properties against clinically significant pathogens. Antimicrobial activity was determined by MIC and microplate absorbance of the synthesized compounds using roxithromycin as a reference standard. The microbiological study showed that the compounds possess promising antibacterial properties. All the title compounds were tested for their in vitro preliminary antimicrobial properties against six bacterial strains, Staphylococcus aureus ATCC- 6538, Bacillus subtilis ATCC-6633, Escherichia coli ATCC-25922, Klebsiella pneumoniae ATCC-1705, Pseudomonas aeruginosa ATCC-15442, Resistant coli ATCC-BAA2452, and four fungal strains, Aspergillus fumigatus FCBP-066, Mucor species FCBP-0300, Fusarium solani FCBP#0291, Aspergillus flavus FCBP-0064 by well plate method. The title compounds exhibited moderate to high specific antifungal activity. Clotrimazole was used as a reference standard. The synthesized compounds showed varying but promising antimicrobial activities, with increased potency against Gram-positive bacteria over Gram-negative bacteria. Compounds AK7 and AK9 showed strong antifungal activity against A. fumigatus with MIC of 12.5 and 10.37 µg/disc, respectively, similar to clotrimazole. The results of the structure-activity relationship (SAR) study showed that electron-withdrawing groups and optimal lipophilicity were essential in increasing the antimicrobial activity. The results of this study emphasize the potential of 2-mercaptobenzimidazole Mannich compounds as promising lead compounds for further optimization.

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Published

2026-02-28

Issue

Vol. 4 No. 2 (2026): Indus Journal of Bioscience Research

Section

Original Article

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Copyright (c) 2026 Indus Journal of Bioscience Research

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This work is licensed under a Creative Commons Attribution 4.0 International License.

How to Cite

Ali Kharl, H. A., Shamim, A., Farooq, M. A., Tahir, A., Khan, S., Khan, S., Iqbal, S., Khan, M., Masaud, S. M., & Ali, M. M. (2026). In-Vitro Antibacterial and Antifungal Evaluation of 2-Mercaptobenzimidazole Mannich Based Derivatives:Structure Activity Relationship and MIC Analysis against clinically relevant pathogens. Indus Journal of Bioscience Research, 4(2), 165-171. https://doi.org/10.70749/ijbr.v4i2.2892