Discovery and analgesic evaluation of 8-chloro-1,4-dihydropyrido[2,3-b]pyrazine-2,3-dione as a novel potent d-amino acid oxidase inhibitor

Eur J Med Chem. 2016 Jul 19:117:19-32. doi: 10.1016/j.ejmech.2016.04.017. Epub 2016 Apr 9.

Abstract

A series of 5-azaquinoxaline-2,3-dione derivatives were synthesized and evaluated on d-amino acid oxidase (DAAO) inhibition as potential α-hydroxylactam-based inhibitors. The potent inhibitory activities in vitro suggested that 5-nitrogen could significantly enhance the binding affinity by strengthening relevant hydrogen bond interactions. The analgesic effects of intrathecal and systemic injection of 8-chloro-1,4-dihydropyrido[2,3-b]pyrazine-2,3-dione, a representative molecule of 5-azaquinoxaline-2,3-dione, were investigated in rodents. This research not only confirmed the analgesic effect of the DAAO inhibitors but provided a new class of chemical entities with oral application potential for the treatment of chronic pain and morphine analgesic tolerance.

Keywords: 5-Azaquinoxaline-2,3-diones; 8-Chloro-1,4-dihydropyrido[2,3-b]pyrazine-2,3-dione; Analgesic effects; D-amino acid oxidase; DAAO inhibitors.

MeSH terms

  • Analgesics / chemical synthesis*
  • Analgesics / pharmacology
  • Animals
  • D-Amino-Acid Oxidase / antagonists & inhibitors*
  • Drug Discovery / methods
  • Drug Tolerance
  • Enzyme Inhibitors / chemical synthesis*
  • Enzyme Inhibitors / pharmacology
  • Mice
  • Morphine / pharmacology
  • Quinoxalines / chemical synthesis*
  • Quinoxalines / pharmacology

Substances

  • Analgesics
  • Enzyme Inhibitors
  • Quinoxalines
  • Morphine
  • Dao1 protein, mouse
  • D-Amino-Acid Oxidase