DL-2-Amino-3-phosphonopropionic acid (AP3)

DL-2-Amino-3-phosphonopropionic acid (DL-AP3), a racemic preparation of D-AP3 and L-AP3, is an inhibitor of phosphoserine phosphatase and an antagonist of the receptor mGluR( metabotropic glutamate receptor), blocking phosphoinositide turnover mediated by the mGluR. D-AP3 demonstrates more potent inhibition of phosphoserine phosphatase than L-AP3, and D-AP3 is specifically active at phosphoserine phosphatase while L-AP3 produces mGluR antagonism with similar potency to its inhibition of phosphoserine phosphatase. L-AP3 is described to antagonize the metabotropic Ca²⁺ mobilizing effects of the mGluR agonist Trans-ACPD while D-AP3 shows no such antagonism.