Structural modification of ciprofloxacin and norfloxacin for searching new antibiotics to combat drug-resistant bacteria

The aim of the work. Among all representatives four generations fluoroquinolones ciprofloxacin (CIPRO) and norfloxacin (NOR) remain widely used prescribed antibiotics in clinical practice. However, problem resistance towards them is gradually increasing. Thus, our investigation dedicated to chemical modification C-7 position Ciprofloxacin Norfloxacin ring as a promising solution combat antibiotic open pathway convenient synthesis new derivatives.
 Materials methods. subjects research were N-piperazine-substituted norfloxacin. methods molecular docking organic applied study. structures obtained compounds confirmed by 1H NMR, 13C 19F LC/MS, IR, UV spectroscopy. antimicrobial activity was measured method double serial dilutions against Staphylococcus aureus (ATCC 25923), Escherichia coli 25922), Bacillus subtilis 6633), Pseudomonas aeruginosa 27853), Candida albicans (NCTC 885-653) diffusion agar strains.
 results. 7-(4-(2-Cyanoacetyl)piperazin-1-yl)-1-R-6-fluoro-4-oxo-1,4-dihydroquinoline-3-carboxylic acids synthesized their confirmed. showed antibacterial on reference level for dilution exceeded control “well” method.
 Conclusions. current revealed route expanding existing diversity. Pharmacodynamics pharmacokinetics changes could be achieved modifications initial ring. Further utilizing starting ones opens way novel active molecules combating