Unexpected reaction of 2-alkylsulfanylimidazoles to imidazol-2-ones: pyridinylimidazol-2-ones as novel potent p38alpha mitogen-activated protein kinase inhibitors

J Med Chem. 2010 Jun 24;53(12):4798-802. doi: 10.1021/jm100161q.

Abstract

While optimizing the synthesis of 2-alkylsulfanyl-5-(2-aminopyridin-4-yl)imidazoles, we identified an unexpected reaction to pyridinylimidazol-2-ones. 2-Alkylsulfanylimidazoles, bearing a 2-hydroxyethyl or a 2,3-dihydroxypropyl moiety at the imidazole C2-S position, were converted by heating into imidazol-2-ones. These imidazol-2-ones were tested for their ability to inhibit p38alpha MAP kinase and LPS-stimulated TNF-alpha release in HWB. Introduction of an amino moiety at the pyridine C2 position led to compounds showing potent enzyme inhibitory activity with double-digit nanomolar IC(50) values (5a: IC(50) = 23 nM).

MeSH terms

  • Humans
  • Imidazoles / chemical synthesis*
  • Imidazoles / chemistry
  • Imidazoles / pharmacology
  • In Vitro Techniques
  • Lipopolysaccharides / pharmacology
  • Mitogen-Activated Protein Kinase 14 / antagonists & inhibitors*
  • Models, Molecular
  • Pyridines / chemical synthesis*
  • Pyridines / chemistry
  • Pyridines / pharmacology
  • Stereoisomerism
  • Structure-Activity Relationship
  • Sulfides / chemical synthesis*
  • Sulfides / chemistry
  • Sulfides / pharmacology
  • Tumor Necrosis Factor-alpha / blood

Substances

  • Imidazoles
  • Lipopolysaccharides
  • Pyridines
  • Sulfides
  • Tumor Necrosis Factor-alpha
  • Mitogen-Activated Protein Kinase 14