New pyrrole derivatives as DNA gyrase and 14α-demethylase inhibitors: Design, synthesis, antimicrobial evaluation, and molecular docking.

An efficient one-pot reaction utilizing readily available chemical reagents was used to prepare novel 2-amino-1,5-diaryl-1H-pyrrole-3-carbonitrile derivatives and the structures of these compounds were validated by spectroscopic data and elemental analyses. All the synthetic compounds were evaluated for their antimicrobial activities (MZI assay). The tested compounds proved high activities on Staphylococcus aureus (Gram-positive bacteria) and Candida albicans (Pathogenic fungi). However, they did not show any activity on Escherichia coli (Gram-negative bacteria). The most effective compounds in MZI assay 7c, 9a, 9b, 11a, and 11b were selected to determine their MIC on S. aureus and C. albicans. Furthermore, DNA gyrase and 14-α demethylase inhibitory assays were performed to study the inhibitory activities of 7c, 9a, 9b, 11a, and 11b. The results illustrated that compound 9b was the most DNA gyrase inhibitor (IC 50 of 0.0236 ± 0.45 µM, which was 1.3- fold higher than gentamicin reference IC 50 values of 0.0323 ± 0.81 µM). In addition, compound 9b demonstrated the highest 14-α demethylase inhibitory effect with IC 50 of 0.0013 ± 0.02 µM, compared to ketoconazole (IC 50 of 0.0008 ± 0.03 µM) and fluconazole (IC 50 of 0.00073 ± 0.01 µM), as antifungal reference drugs. Lastly, docking studies were performed to rationalize the dual inhibitory activities of the highly active compounds on both DNA gyrase and 14-α demethylase enzymes.