Synthesis, pharmacological and structural studies of 5-substituted-3-(1-arylmethyl-1,2,3,6-tetrahydropyridin-4-yl)-1H-indoles as multi-target ligands of aminergic GPCRs

Eur J Med Chem. 2019 Oct 15:180:673-689. doi: 10.1016/j.ejmech.2019.07.050. Epub 2019 Jul 20.

Abstract

Schizophrenia is a complex disease with not fully understood pathomechanism, involving many neurotransmitters and their receptors. This is why it is best treated with multi-target drugs, such as second generation antipsychotics. Here we present 5-substituted-3-(1-arylmethyl-1,2,3,6-tetrahydropyridin-4-yl)-1H-indoles (1-20) which are ligands of dopamine D2 and serotonin 5-HT1A and 5-HT2A receptors and display affinity in the nanomolar range. These compounds were designed as modifications of the virtual hit experimentally confirmed, D2AAK1, and synthesized from indole or 5-alkoxyindoles and N-substituted piperidin-4-ones in methanol in the presence of potassium hydroxide. Compound 9 was subjected to X-ray studies and it crystallizes in the centrosymmetric monoclinic space group P21/c with one molecule in an asymmetric unit. Three most potent compounds (5, 9 and 17) turned out to be antagonists of both D2 and 5-HT2A receptors what is beneficial for their potential application as antipsychotics. Compound 5 was subjected to behavioral studies and exhibited antipsychotic, pro-cognitive and antidepressant activity in appropriate mice models. Structure-activity relationships for compounds 1-20 were rationalized using molecular docking. It was found that, in general, bulky C5-alkoxy substituents at the indole moiety are not favorable as they direct towards aqueous environment of the extracellular vestibule. Keywords: antipsychotics; behavioral studies, G protein-coupled receptors; indole derivatives; multi-target compounds; schizophrenia.

MeSH terms

  • Animal Migration / drug effects
  • Animals
  • Antipsychotic Agents / chemical synthesis
  • Antipsychotic Agents / chemistry
  • Antipsychotic Agents / pharmacology*
  • CHO Cells
  • Cricetulus
  • Disease Models, Animal
  • Dose-Response Relationship, Drug
  • HEK293 Cells
  • Humans
  • Indoles / chemical synthesis
  • Indoles / chemistry
  • Indoles / pharmacology*
  • Ligands
  • Male
  • Mice
  • Molecular Structure
  • Receptors, G-Protein-Coupled / antagonists & inhibitors*
  • Receptors, G-Protein-Coupled / metabolism
  • Structure-Activity Relationship

Substances

  • Antipsychotic Agents
  • Indoles
  • Ligands
  • Receptors, G-Protein-Coupled