The purpose of the present study was to evaluate the antimicrobial effects of 3-hetarylazoquinoline-2,4-diols (19), having substituted or unsubstituted thiazole, benzothiazole, benzimidazole, triazole, isoxazole, and thiadiazole moieties at the 3-position, on bacterial and yeast strains. In addition, compounds and DNA interaction with pUC18 plasmid DNA were studied. The biological effects of these molecules were compared with potential antibiotics ampicillin,~chloramfenicol (for bacteria), and ketoconozole (for yeast). According to the results, all compounds except 8 have mild to moderate activity against some of the bacterial strains tested, and none of the compounds have activity against the fungi C. tropicalis and C. albicans. Compounds 1 and 6 have moderate activities against B. cereus and B. subtilis, and compounds 5 and 6 have moderate activities and 1 has mild activity against E. coli. Compound 2 has a mild effect on all bacterial strains except E. coli ATCC 25922, P. vulgaris, and S. aureus. Compounds 3-5 and 7 have mild activity against some of the bacterial strains tested. Compound 9 has mild activity against all bacterial strains except E. coli ATCC 25922. Compound 8 has no antibacterial effect. Compounds and DNA interaction results indicate that as the compounds bind to DNA, unwinding of supercoiled form I DNA takes place to change it from the negatively supercoiled form I to the nicked form II and linear form III DNA. The following studies showed that, among the synthesized compounds, 3-9 seem to be promising candidates possessing DNA cleavage activities besides anti-microbial properties to serve as chemical nucleases and chemotherapeutic agents.

The purpose of the present study was to evaluate the antimicrobial effects of 3-hetarylazoquinoline-2,4-diols (19), having substituted or unsubstituted thiazole, benzothiazole, benzimidazole, triazole, isoxazole, and thiadiazole moieties at the 3-position, on bacterial and yeast strains. In addition, compounds and DNA interaction with pUC18 plasmid DNA were studied. The biological effects of these molecules were compared with potential antibiotics ampicillin,~chloramfenicol (for bacteria), and ketoconozole (for yeast). According to the results, all compounds except 8 have mild to moderate activity against some of the bacterial strains tested, and none of the compounds have activity against the fungi C. tropicalis and C. albicans. Compounds 1 and 6 have moderate activities against B. cereus and B. subtilis, and compounds 5 and 6 have moderate activities and 1 has mild activity against E. coli. Compound 2 has a mild effect on all bacterial strains except E. coli ATCC 25922, P. vulgaris, and S. aureus. Compounds 3-5 and 7 have mild activity against some of the bacterial strains tested. Compound 9 has mild activity against all bacterial strains except E. coli ATCC 25922. Compound 8 has no antibacterial effect. Compounds and DNA interaction results indicate that as the compounds bind to DNA, unwinding of supercoiled form I DNA takes place to change it from the negatively supercoiled form I to the nicked form II and linear form III DNA. The following studies showed that, among the synthesized compounds, 3-9 seem to be promising candidates possessing DNA cleavage activities besides anti-microbial properties to serve as chemical nucleases and chemotherapeutic agents.