To design and synthesize a series of new quinolones which would provide improved Gram-positive antibacterial activity, while retaining the good Gram-negative activity. The substance, L-proline (1), was reacted with MeOH to give 2, then reacted with BzCl to give 3; 3 reacted with NH3 · H2O to afforded 4, which was reduced by LiAlH4 to give 5, 5 was protected by BOC to afford 6, which reacted with H2 to give 7. Compound 7 was condensed with five quinolone nucleus to obtain 8∼12. At last, the BOC groups were hydrolyzed to give 13∼17. In this article, twelve unreported compounds (13∼17) were synthesized. The in vitro antibacterial activity of five target compounds (13∼17) were tested against 10 Gram-positive and 10 Gram-negative organisms. The compound 15 (MIC 0.12μg/ml) showed an excellent activity against S. pneumoniae, which was consistent with gatifloxacin (MIC 0.12μg/ml), but better than ciprofloxacin (MIC 0.5∼2 μg/ml). Nevertheless, the compound 15 (MIC 0.5∼32μg/ml) showed lower activity against other organisms than gatifloxacin (MIC 0.03∼2μg/ml). All the other four compounds (13, 14, 16, 17) (MIC 0.25∼>64 μg/ml) showed lower activity than gatifloxacin and ciprofloxacin.
|Original language||English (US)|
|Journal||Chinese Journal of Antibiotics|
|State||Published - Sep 23 2004|
- Antibacterial activity
- Quinolone derivatives
ASJC Scopus subject areas