Facile synthesis and <italic>in vitro/vivo</italic> bioactivities of amido derivatives of clinafloxacin

Abstract

Nineteen new amido derivatives of clinafloxacin (CF) were prepared in 52.8%～97.5% via the condensation of selected carboxylic acids with clinafloxacin. The chemical structures of these target molecules were confirmed by 1H NMR, 13C NMR and HR MS. Following the preliminary evaluation of antibacterial activity through agar diffusion method, the minimal inhibitory concentrations (MICs) of all the obtained amido derivatives of CF were measured by Micro-dilution method. The toxicity of the active compounds of interest was confirmed by acute toxicity test in mice. The stability of most of target compounds was detected by use of the general agar diffusion procedure on the keeping time of 30–90 days, subsequently. The results showed that TM1-b and TM1-l possessed stronger antibacterial activity, lower toxicity, larger solubility and higher stability than CF, and thus may be exploitable as lead compounds. This finding may provide some helpful guidances for further investigation.