ANTIMICROBIAL AND CHITINASE INHIBITORY ACTIVITIES OF 7-BENZAMIDOCOUMARINS

• Published in: Asian journal of pharmaceutical and clinical research 2019-05, p.114-119
• Main Authors: NEHA TIWARI, PRIYANKA, VINEETA SINGH, DIKSHA KATIYAR
• Format: Article
• Language: English
• ISSN: 0974-2441; 0974-2441
• DOI: 10.22159/ajpcr.2019.v12i7.33155

Objective: The aim of this study was to examine in vitro antimicrobial activity of a series of 7-benzamidocoumarin derivatives against three Gram-positive bacteria (Bacillus subtilis, Staphylococcus aureus, and Bacillus pumilus), three Gram-negative bacteria (Escherichia coli, Klebsiella pneumonia, and Salmonella typhi), and three fungi (Candida albicans, Candida tropicalis, and Aspergillus niger) by 2-fold serial dilution method. Materials and Methods: The compounds were synthesized by amide coupling of 7-amino-4-methyl coumarin 5 and 7-amino-4-chloromethyl coumarin 6 with different aromatic acids 7 (a-h) and heteroaromatic acids 8 (i-j) in the presence of phosphorous trichloride as an acid catalyst in acetonitrile. The synthesized compounds were evaluated for antimicrobial and chitinase inhibitory activity. Results: Compounds 9, 11, 12, 21, and 23 showed good antibacterial activity with minimum inhibitory concentration (MIC) ranging from 6.25 to 50 μg/mL. Among them, compound 21 was the most active molecule with MIC 6.25 μg/mL against S. aureus and 6.25 μg/mL against, B. pumilus and S. typhi. Compounds 11 and 21 were the most potent antifungal candidates with MIC 6.25–25 μg/mL against C. albicans and C. tropicalis. All the compounds were also evaluated for their chitinase inhibitory property and among them; compound 9 emerged as strong inhibitor of the enzyme. Conclusion: Some of the compounds showed very good antimicrobial activities. Among these, compound 21 showing potent antimicrobial activities against five of the nine microbial strains examined in this study, was the most active compound of the series. Some of the compounds also showed chitinase inhibitory properties. This study also provides a starting point for investigating the structure-activity relationships (SARs) of synthetic 7-benzamidocoumarins.