Thiazolopyridine ureas as novel antitubercular agents acting through inhibition of DNA Gyrase B

J Med Chem. 2013 Nov 14;56(21):8834-48. doi: 10.1021/jm401268f. Epub 2013 Oct 18.

Abstract

A pharmacophore-based search led to the identification of thiazolopyridine ureas as a novel scaffold with antitubercular activity acting through inhibition of DNA Gyrase B (GyrB) ATPase. Evaluation of the binding mode of thiazolopyridines in a Mycobacterium tuberculosis (Mtb) GyrB homology model prompted exploration of the side chains at the thiazolopyridine ring C-5 position to access the ribose/solvent pocket. Potent compounds with GyrB IC50 ≤ 1 nM and Mtb MIC ≤ 0.1 μM were obtained with certain combinations of side chains at the C-5 position and heterocycles at the C-6 position of the thiazolopyridine core. Substitutions at C-5 also enabled optimization of the physicochemical properties. Representative compounds were cocrystallized with Streptococcus pneumoniae (Spn) ParE; these confirmed the binding modes predicted by the homology model. The target link to GyrB was confirmed by genetic mapping of the mutations conferring resistance to thiazolopyridine ureas. The compounds are bactericidal in vitro and efficacious in vivo in an acute murine model of tuberculosis.

MeSH terms

  • Animals
  • Antitubercular Agents / administration & dosage
  • Antitubercular Agents / chemistry
  • Antitubercular Agents / pharmacology*
  • DNA Gyrase / metabolism*
  • Disease Models, Animal
  • Dose-Response Relationship, Drug
  • Mice
  • Mice, Inbred BALB C
  • Models, Molecular
  • Molecular Structure
  • Mycobacterium tuberculosis / drug effects*
  • Mycobacterium tuberculosis / enzymology
  • Pyridines / administration & dosage
  • Pyridines / chemistry
  • Pyridines / pharmacology*
  • Structure-Activity Relationship
  • Topoisomerase II Inhibitors / administration & dosage
  • Topoisomerase II Inhibitors / chemistry
  • Topoisomerase II Inhibitors / pharmacology*
  • Tuberculosis / drug therapy*
  • Urea / analogs & derivatives
  • Urea / chemistry
  • Urea / pharmacology*

Substances

  • Antitubercular Agents
  • Pyridines
  • Topoisomerase II Inhibitors
  • Urea
  • DNA Gyrase