LY341495 is a potent, brain-permeable, and selective antagonist of the group II metabotropic glutamate receptors (mGluR), mGluR2 and mGluR3 (IC50s = 21 and 14 nM, respectively, for human isoforms). It less effectively blocks mGluR8 and mGluR7 (IC50s = 173 and 990 nM, respectively) and weakly antagonizes mGluR1, mGluR5, and mGluR4 (IC50s = 6.8, 8.2, and 22 μM, respectively). MW: 353.37. Purity ≥98% by HPLC