Synthesis, Characterization, and Biological Evaluation of New Cyclic Quinazoline Derivatives as Potential Antibacterial and Antifungal Agents

Heterocyclic compounds are crucial for medicinal chemistry and the development of therapeutic agents like broad-spectrum antibiotics. This study devised a facile procedure to synthesize novel antimicrobial bicyclic heterocycles from 2-mercapto-3-phenylquinazolin-4(3H)-one. Advanced analytical techniques including ¹H and ¹³C NMR, elemental analysis, and FT-IR spectroscopy characterized the intricate chemical structures of the products. In vitro assays tested the heterocycles against aerobic and anaerobic bacterial strains using fluconazole and ciprofloxacin as antifungal and antibacterial controls. Results demonstrated the formidable broad-spectrum antibacterial and antifungal activities of the synthesized compounds, with growth inhibition approaching that of the positive controls. These findings highlight the immense potential of these novel heterocyclic compounds as antimicrobial agents. Further research can optimize their drug-like properties for eventual clinical use in combating drug-resistant infections.