Design, synthesis and antimicrobial evaluation of propylene-tethered ciprofloxacin-isatin hybrids

Twelve novel propylene-tethered isatin-ciprofloxacin hybrids 3a-f and 4a-f were designed, synthesized and evaluated for their in vitro antimicrobial activities against representative Gram-positive, Gram-negative and mycobacterial pathogens, cytotoxicity in VERO cell line as well as metabolic stability and in vivo pharmacokinetic (PK) properties. The preliminary results indicated that all mono-isatin-ciprofloxacin hybrids exhibited excellent antibacterial activities with MIC ranging from ≤0.03 to 0.5 μg/mL against most of the tested strains.160