Discovery of molecular switches that modulate modes of metabotropic glutamate receptor subtype 5 (mGlu5) pharmacology in vitro and in vivo within a series of functionalized, regioisomeric 2- and 5-(phenylethynyl)pyrimidines

J Med Chem. 2009 Jul 23;52(14):4103-6. doi: 10.1021/jm900654c.


We describe the synthesis and SAR of a series of analogues of the mGlu(5) partial antagonist 5-(phenylethynyl)pyrimidine. New molecular switches are identified that modulate the pharmacological activity of the lead compound. Slight structural modifications around the proximal pyrimidine ring change activity of the partial antagonist lead to that of potent and selective full negative allosteric modulators and positive allosteric modulators, which demonstrate in vivo efficacy in rodent models for anxiolytic and antipsychotic activity, respectively.

Publication types

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

MeSH terms

  • Allosteric Regulation
  • Animals
  • Dose-Response Relationship, Drug
  • Humans
  • Inhibitory Concentration 50
  • Pyrimidines / chemical synthesis
  • Pyrimidines / chemistry*
  • Pyrimidines / pharmacology*
  • Rats
  • Receptor, Metabotropic Glutamate 5
  • Receptors, Metabotropic Glutamate / antagonists & inhibitors*
  • Stereoisomerism
  • Structure-Activity Relationship


  • Pyrimidines
  • Receptor, Metabotropic Glutamate 5
  • Receptors, Metabotropic Glutamate