Rigidified analog of MPPG (Cat. No. 0853); selective group II metabotropic glutamate receptor antagonist (IC50 = 30 μM) with no significant effect on group I and III mGlu receptors at concentrations up to 1 mM. Increases extracellular glutamate concentrations and possesses unusual inverse agonist-like action. MW (observed): 257.18.