Highly potent and selective inhibitor of? glutamate carboxypeptidase 2 (GCP II/N-acetylated α -linked dipeptidase/NAALADase) with a K i value of 275 pM. Neuroprotective; protects against glutamate-mediated motor neuron degeneration and reduces volume of injury following middle cerebral artery occlusion (MCAO).