Synthesis and in vitro Evaluation of Dihydrobenzimidazole Thiopyranooxazinone Derivatives as a Potent Biological Agents

In the present study, dihydrobenzimidazole thiopyranooxazinone derivatives were efficiently synthesized, which were further characterized and authenticated by means of TLC and different spectral analysis such as IR and 1H NMR. The synthesized compounds DPK2d2 to DPK2d8 were screened for their in vitro antimicrobial, antitubercular and anticancer activities. The results showed that the titled compounds DPK3d1, DPK3d2 and DPK3d4 exhibited potent antimicrobial activity, shows a broadspectrum activity against Bacillus subtilis, Escherichia coli (antibacterial) and Aspergillus niger (antifungal) as compared to ciprofloxacin and fluconazole, respectively. Compounds DPK3d1, DPK3d3 and DPK3d5 exhibited potent antitubercular activities against Mycobacterium tuberculosis as compared to pyrazinamide, ciprofloxacin and streptomycin. Compounds DPK3d3, DPK3d4 and DPK3d5 showed highly potent cytotoxic activity against human lung cancer cell line (A549) as compared to adriamycin. In silico molecular docking studies shown that all the ligands highest binding affinity range -6.7 to -8.7 for selected 1CB4 PDB of superoxide dismutase, which recognized that ligands having antioxidant activity.