Study on new series of bis-benzimidazole derivatives synthesis, characterization, single crystal XRD, biological activity and molecular docking

Abstract

This research work defines the synthesis of bis-benzimidazole derivatives using simple and eco-friendly reaction condition and crystallization procedure. Structure of compounds were established by 1H NMR, 13C NMR and mass spectroscopic techniques. Among all derivatives compound 1c possess crystal nature and demonstrated by single crystal X-ray study. The synthesized bis-benzimidazole series compounds were screened for antimicrobial activity against human bacterial pathogen includes Gram-positive bacteria Bacillus subtilis, Staphylococcus aureus, and Gram-negative bacteria Escherichia coli, Serratia sp. and Fungal pathogens Candida albicans. Among all the compounds, 1e shows best activity compared with other compounds, the minimum inhibitory concentration of 1e for C. albicans shows 16 µg/mL concentrations as the best inhibition. The hemolytic activity of purified compound at 1% of lysis shows 100 µg/mL concentration and the remaining concentration shows no hemolysis. Molecular docking of 1g in fungal proteins C. albicans was carried out (Dihydrofolate Reductase PDB id: 1IA4), in which pose 1 shows the best binding energy −6.23 kJ mol−1.