Novel human adenosine receptor antagonists based on the 7-amino-thiazolo[5,4-d]pyrimidine scaffold. Structural investigations at the 2-, 5- and 7-positions to enhance affinity and tune selectivity

Bioorg Med Chem Lett. 2019 Feb 15;29(4):563-569. doi: 10.1016/j.bmcl.2018.12.062. Epub 2018 Dec 31.

Abstract

This paper describes the synthesis of novel 7-amino-thiazolo[5,4-d]pyrimidines bearing different substituents at positions 2, 5 and 7 of the thiazolopyrimidine scaffold. The synthesized compounds 2-27 were evaluated in radioligand binding (A1, A2A and A3) and adenylyl cyclase activity (A2B and A2A) assays, in order to evaluate their affinity and potency at human adenosine receptor subtypes. The current study allowed us to support that affinity and selectivity of 7-amino-thiazolo[5,4-d]pyrimidine derivatives towards the adenosine receptor subtypes can be modulated by the nature of the groups attached at positions 2, 5 and 7 of the bicyclic scaffold. To rationalize the hypothetical binding mode of the newly synthesized compounds, we also performed docking calculations in human A2A, A1 and A3 structures.

Keywords: Adenosine receptor antagonists; Adenosine receptors; Bicyclic heteroaromatic system; G protein coupled receptors; Thiazolopyrimidine derivatives.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • CHO Cells
  • Cricetulus
  • Humans
  • Molecular Docking Simulation
  • Purinergic P1 Receptor Antagonists / chemistry
  • Purinergic P1 Receptor Antagonists / pharmacology*
  • Pyrimidines / chemical synthesis*
  • Pyrimidines / chemistry
  • Pyrimidines / pharmacology*
  • Radioligand Assay
  • Structure-Activity Relationship
  • Thiazoles / chemistry*

Substances

  • Purinergic P1 Receptor Antagonists
  • Pyrimidines
  • Thiazoles