Synthesis of new 5,6,7,8-tetrahydropyrido[1,2-c]pyrimidine derivatives with rigidized tryptamine moiety as potential SSRI and 5-HT1A receptor ligands

Eur J Med Chem. 2019 Oct 15:180:383-397. doi: 10.1016/j.ejmech.2019.07.027. Epub 2019 Jul 12.

Abstract

Extended studies in the 4-aryl-pyrido[1,2-c]pyrimidine group resulted in 27 new compounds (10.1-10.27), 5,6,7,8-tetrahydropyrido[1,2-c]pyrimidine derivatives. In vitro tests (RBA) were carried out for 10.1-10.27 compounds in order to determine their affinity to 5-HT1A receptor and SERT protein. 10.1-10.3, 10.6, 10.7, 10.16 and 10.27 compounds had high binding ability to both molecular targets (5-HT1A Ki = 8-87 nM; SERT Ki = 8-52 nM). For these compounds (10.1-10.3, 10.6, 10.7, 10.16, 10.27) further in vitro, in vivo and metabolic stability tests were performed. In vitro studies in the extended receptor profile (D2, 5-HT2A, 5-HT6 and 5-HT7) showed their selectivity towards 5-HT1A receptor and SERT protein. In vivo tests revealed that compounds 10.7 and 10.16 had the properties of presynaptic antagonists of the 5-HT1A receptor. The redesign of the 2H-pyrido[1,2-c]pyrimidine residue present in the terminal part towards 5,6,7,8-tetrahydropyrido[1,2-c]pyrimidine resulted in the improved metabolic stability and enhanced affinity to both molecular targets (5-HT1A-R and SERT) compared to the precursors.

Keywords: Antidepressants; Dual 5-HT(1A)/SERT activity; Pyrido[1,2-c]pyrimidines.

MeSH terms

  • Animals
  • Cells, Cultured
  • Crystallography, X-Ray
  • Dose-Response Relationship, Drug
  • HEK293 Cells
  • Humans
  • Ligands
  • Male
  • Mice
  • Models, Molecular
  • Molecular Structure
  • Pyrimidines / chemical synthesis
  • Pyrimidines / chemistry
  • Pyrimidines / pharmacology*
  • RNA-Binding Proteins / antagonists & inhibitors*
  • RNA-Binding Proteins / metabolism
  • Rats
  • Receptor, Serotonin, 5-HT1A / metabolism*
  • Structure-Activity Relationship
  • Tryptamines / chemistry
  • Tryptamines / pharmacology*

Substances

  • Ligands
  • Pyrimidines
  • RNA-Binding Proteins
  • Sert1 protein, rat
  • Tryptamines
  • Receptor, Serotonin, 5-HT1A
  • tryptamine
  • pyrimidine