Dipicolinic Acid Derivatives as Inhibitors of New Delhi Metallo-β-lactamase-1

J Med Chem. 2017 Sep 14;60(17):7267-7283. doi: 10.1021/acs.jmedchem.7b00407. Epub 2017 Aug 30.

Abstract

The efficacy of β-lactam antibiotics is threatened by the emergence and global spread of metallo-β-lactamase (MBL) mediated resistance, specifically New Delhi metallo-β-lactamase-1 (NDM-1). By utilization of fragment-based drug discovery (FBDD), a new class of inhibitors for NDM-1 and two related β-lactamases, IMP-1 and VIM-2, was identified. On the basis of 2,6-dipicolinic acid (DPA), several libraries were synthesized for structure-activity relationship (SAR) analysis. Inhibitor 36 (IC50 = 80 nM) was identified to be highly selective for MBLs when compared to other Zn(II) metalloenzymes. While DPA displayed a propensity to chelate metal ions from NDM-1, 36 formed a stable NDM-1:Zn(II):inhibitor ternary complex, as demonstrated by 1H NMR, electron paramagnetic resonance (EPR) spectroscopy, equilibrium dialysis, intrinsic tryptophan fluorescence emission, and UV-vis spectroscopy. When coadministered with 36 (at concentrations nontoxic to mammalian cells), the minimum inhibitory concentrations (MICs) of imipenem against clinical isolates of Eschericia coli and Klebsiella pneumoniae harboring NDM-1 were reduced to susceptible levels.

MeSH terms

  • Anti-Bacterial Agents / chemistry
  • Anti-Bacterial Agents / pharmacology
  • Escherichia coli / drug effects
  • Escherichia coli / enzymology*
  • Escherichia coli Infections / drug therapy
  • Escherichia coli Infections / microbiology
  • Humans
  • Klebsiella Infections / drug therapy
  • Klebsiella Infections / microbiology
  • Klebsiella pneumoniae / drug effects
  • Klebsiella pneumoniae / enzymology*
  • Microbial Sensitivity Tests
  • Picolinic Acids / chemistry*
  • Picolinic Acids / pharmacology*
  • Structure-Activity Relationship
  • beta-Lactamase Inhibitors / chemistry*
  • beta-Lactamase Inhibitors / pharmacology*
  • beta-Lactamases / metabolism*

Substances

  • Anti-Bacterial Agents
  • Picolinic Acids
  • beta-Lactamase Inhibitors
  • beta-Lactamases
  • beta-lactamase NDM-1
  • dipicolinic acid