Synthesis, characterization and in vitro antimicrobial and antimycobacterial activity of novel quinazolinone–flouroquinolone hybrids

Novel quinazoline-flouroquinolone hybrids are synthesized using ciprofloxacin/gatifloxacin and 2-chloromethyl-3-(N-isonicotinamide-yl)–substituted-4H-quinazolinone (3a-j). The synthesized compounds were characterized on the basis of their elemental and spectral analysis (IR, 1H-NMR, 13C-NMR and mass spectrometry). All newly synthesized compounds were evaluated for their in vitro antimycobacterial activity against Mycobacterium tuberculosis H37Rv, in vitro antibacterial activity against selected human pathogens Escherichia coli, Pseudomonas aeruginosa, Klebsiella pneumoniae, Salmonella typhi, Staphylococcus aureus, Streptococcus pyogenes, Bacillus subtilis and antifungal activity against Candida albicans, Aspergillus niger, A. clavatus strains. The in vitro antimicrobial data suggest that 6-bromo and 8-bromo compounds are more active and also ciprofloxacin derivatives are more potent than gatifloxacin.