A potent and selective antagonist of the group II metabotropic glutamate receptors mGluR2 and mGluR3 (IC₅₀s = 21 and 14 nM, respectively); less effectively blocks mGluR8 and mGluR7 (IC₅₀s = 173 and 990 nM, respectively) can be effectively used in isolated cells, tissues, and…