Hybrid antibacterials. DNA polymerase-topoisomerase inhibitors

J Med Chem. 2006 Feb 23;49(4):1455-65. doi: 10.1021/jm0510023.


Novel Gram-positive (Gram+) antibacterial compounds consisting of a DNA polymerase IIIC (pol IIIC) inhibitor covalently connected to a topoisomerase/gyrase inhibitor are described. Specifically, 3-substituted 6-(3-ethyl-4-methylanilino)uracils (EMAUs) in which the 3-substituent is a fluoroquinolone moiety (FQ) connected by various linkers were synthesized. The resulting "AU-FQ" hybrid compounds were significantly more potent than the parent EMAU compounds as inhibitors of pol IIIC and were up to 64-fold more potent as antibacterials in vitro against Gram+ bacteria. The hybrids inhibited the FQ targets, topoisomerase IV and gyrase, with potencies similar to norfloxacin but 10-fold lower than newer agents, for example, ciprofloxacin and sparfloxacin. Representative hybrids protected mice from lethal Staphylococcus aureus infection after intravenous dosing, and one compound showed protective effect against several antibiotic-sensitive and -resistant Gram+ infections in mice. The AU-FQ hybrids are a promising new family of antibacterials for treatment of antibiotic-resistant Gram+ infections.

Publication types

  • Research Support, N.I.H., Extramural
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Aniline Compounds / chemical synthesis*
  • Aniline Compounds / pharmacokinetics
  • Aniline Compounds / pharmacology
  • Animals
  • Anti-Bacterial Agents / chemical synthesis*
  • Anti-Bacterial Agents / pharmacokinetics
  • Anti-Bacterial Agents / pharmacology
  • DNA Polymerase III / antagonists & inhibitors*
  • Drug Resistance, Bacterial
  • Gram-Positive Bacteria / drug effects*
  • Male
  • Mice
  • Staphylococcal Infections / drug therapy
  • Staphylococcus aureus / drug effects
  • Structure-Activity Relationship
  • Topoisomerase II Inhibitors*
  • Toxicity Tests, Acute
  • Uracil / analogs & derivatives*
  • Uracil / chemical synthesis*
  • Uracil / pharmacokinetics
  • Uracil / pharmacology


  • Aniline Compounds
  • Anti-Bacterial Agents
  • Topoisomerase II Inhibitors
  • Uracil
  • DNA Polymerase III