New insights into the SAR and drug combination synergy of 2-(quinolin-4-yloxy)acetamides against Mycobacterium tuberculosis

Eur J Med Chem. 2017 Jan 27:126:491-501. doi: 10.1016/j.ejmech.2016.11.048. Epub 2016 Nov 23.

Abstract

2-(Quinolin-4-yloxy)acetamides have been described as potent and selective in vitro inhibitors of Mycobacterium tuberculosis (Mtb) growth. Herein, a new series of optimized compounds were found to demonstrate highly potent antitubercular activity, with minimum inhibitory concentration (MIC) values against drug-susceptible and drug-resistant Mycobacterium tuberculosis strains in the submicromolar range. Furthermore, the most active compounds had no apparent toxicity to mammalian cells, and they showed intracellular activities similar to those of isoniazid and rifampin in a macrophage model of Mtb infection. Use of the checkerboard method to investigate the association profiles of lead compounds with first- and second-line antituberculosis drugs showed that 2-(quinolin-4-yloxy)acetamides have a synergistic effect with rifampin. Ultimately, the good permeability, moderate rates of metabolism and low risk of drug-drug interactions displayed by some of the synthesized compounds indicate that 2-(quinolin-4-yloxy)acetamides may yield candidates to use in the development of novel alternative therapeutics for tuberculosis treatment.

Keywords: Drug-resistant strains; Intracellular activity; Synergism; Tuberculosis.

MeSH terms

  • Acetamides / chemical synthesis
  • Acetamides / chemistry*
  • Acetamides / metabolism
  • Acetamides / pharmacology*
  • Animals
  • Antitubercular Agents / chemical synthesis
  • Antitubercular Agents / chemistry*
  • Antitubercular Agents / metabolism
  • Antitubercular Agents / pharmacology*
  • Drug Resistance, Bacterial / drug effects
  • Drug Synergism
  • Humans
  • Macrophages / drug effects
  • Macrophages / microbiology
  • Mice
  • Microbial Sensitivity Tests
  • Mycobacterium tuberculosis / drug effects*
  • Quinolines / chemistry*
  • RAW 264.7 Cells
  • Structure-Activity Relationship

Substances

  • Acetamides
  • Antitubercular Agents
  • Quinolines