Synthesis and evaluation of 1,2,4-triazolo[1,5-c]pyrimidine derivatives as A2A receptor-selective antagonists

Bioorg Med Chem Lett. 2010 Oct 1;20(19):5690-4. doi: 10.1016/j.bmcl.2010.08.021. Epub 2010 Aug 10.


Movement disorders such as Parkinson's disease and Huntington's disease are serious life-limiting and debilitating movement disorders. Their onset typically occurs from mid-life to late in life, and effective diagnostic techniques for detecting and following the disease course are lacking. Our goal is to develop receptor imaging agents for positron emission tomography (PET) that selectively target the most relevant subtype of adenosine receptors (AR) that are highly expressed in the striatum, that is, the A(2A) AR. To further this goal, we have synthesized and characterized pharmacologically a family of high affinity A(2A) AR ligands, based on the known antagonist, SCH 442416 (R=-Me), which have structural variability on the terminus (R=-Et, -i-Pr, -allyl, and others). A O-fluoroethyl analogue suitable for use as a PET tracer had a K(i) value of 12.4 nM and was highly selective for the A(2A) AR in comparison to the A(1) and A(3) ARs.

Publication types

  • Research Support, N.I.H., Intramural

MeSH terms

  • Adenosine A2 Receptor Antagonists / chemical synthesis*
  • Adenosine A2 Receptor Antagonists / chemistry
  • Adenosine A2 Receptor Antagonists / pharmacology
  • Binding Sites
  • Cell Line
  • Computer Simulation
  • Contrast Media / chemical synthesis*
  • Contrast Media / chemistry
  • Fluorine Radioisotopes / chemistry
  • Humans
  • Positron-Emission Tomography
  • Protein Structure, Tertiary
  • Pyrazoles / chemistry
  • Pyrimidines / chemical synthesis
  • Pyrimidines / chemistry*
  • Receptor, Adenosine A2A / chemistry*
  • Receptor, Adenosine A2A / metabolism
  • Triazoles / chemistry*


  • Adenosine A2 Receptor Antagonists
  • Contrast Media
  • Fluorine Radioisotopes
  • Pyrazoles
  • Pyrimidines
  • Receptor, Adenosine A2A
  • Triazoles
  • 1,2,4-triazole
  • pyrimidine
  • SCH 442416