(RS)-4C3HPG
(RS)-4C3HPG (4-Carboxy-3-hydroxyphenylglycine) is an effective competitive antagonist at the metabotropic glutamate receptor 1 (mGluR1) in the central nervous system, and it is also an agonist at mGluR2/3. (RS)-4C3HPG exhibits neuroprotective effects in an acute global ischemia rat model.