First-in-class DAPK1/CSF1R dual inhibitors: Discovery of 3,5-dimethoxy-N-(4-(4-methoxyphenoxy)-2-((6-morpholinopyridin-3-yl)amino)pyrimidin-5-yl)benzamide as a potential anti-tauopathies agent

Eur J Med Chem. 2019 Jan 15:162:161-175. doi: 10.1016/j.ejmech.2018.10.057. Epub 2018 Nov 2.

Abstract

Kinase irregularity has been correlated with several complex neurodegenerative tauopathies. Development of selective inhibitors of these kinases might afford promising anti-tauopathy therapies. While DAPK1 inhibitors halt the formation of tau aggregates and counteract neuronal death, CSF1R inhibitors could alleviate the tauopathies-associated neuroinflammation. Herein, we report the design, synthesis, biological evaluation, mechanistic study, and molecular docking study of novel CSF1R/DAPK1 dual inhibitors as multifunctional molecules inhibiting the formation of tau aggregates and neuroinflammation. Compound 3l, the most potent DAPK1 inhibitor in the in vitro kinase assay (IC50 = 1.25 μM) was the most effective tau aggregates formation inhibitor in the cellular assay (IC50 = 5.0 μM). Also, compound 3l elicited potent inhibition of CSF1R in the in vitro kinase assay (IC50 = 0.15 μM) and promising inhibition of nitric oxide production in LPS-induced BV-2 cells (55% inhibition at 10 μM concentration). Kinase profiling and hERG binding assay anticipated the absence of off-target toxicities while the PAMPA-BBB assay predicted potentially high BBB permeability. The mechanistic study and selectivity profile suggest compound 3l as a non-ATP-competitive DAPK1 inhibitor and an ATP-competitive CSF1R inhibitor while the in silico calculations illustrated binding of compound 3l to the substrate-binding site of DAPK1. Hence, compound 3l might act as a protein-protein interaction inhibitor by hindering DAPK1 kinase reaction through preventing the binding of DAPK1 substrates.

Keywords: CSF1R; DAPK1; Multifunctional molecules; Neuroinflammation; Tauopathies.

MeSH terms

  • Animals
  • Benzamides / chemistry
  • Benzamides / pharmacology*
  • Binding Sites
  • Cell Line
  • Death-Associated Protein Kinases / pharmacology*
  • Drug Design
  • Humans
  • Mice
  • Molecular Docking Simulation
  • Protein Binding / drug effects
  • Receptors, Granulocyte-Macrophage Colony-Stimulating Factor / physiology*
  • Tauopathies / drug therapy*

Substances

  • Benzamides
  • CSF1R protein, human
  • Receptors, Granulocyte-Macrophage Colony-Stimulating Factor
  • DAPK1 protein, human
  • Death-Associated Protein Kinases