Synthesis of new piperazinyl quinolones and investigation of their in vitro antibacterial activities

  Quinolone antibacterial agents are currently used for the treatment of various bacterial infections. The nature of functional group at the 7 position of the quinolone ring system is known to have strong influence on the spectrum and extent of in vitro antibacterial activity. Accordingly, a series of N-L2- oxo-2-(2- furyl) and N-[2- oxyimino (2- furyl) ethyl] piperazinyl quinolone derivatives were synthesized and evaluated for in vitro antibacterial activity. Compounds having 2- oxo-2-(-2 furyl) ethyl group attached to the piperazine ring were as potent as norfloxacin and ciprofloxacin. The oximes were more active than corresponding ketones and original quinolone s against gram positive bacteria but less active against gram negative bacteria. The methyl oximes and O- benzyloximes were almost a potent as the corresponding quinolones against gram positive bacteria but less active against gram negative bacteria.