Synthesis and biological evaluation of two analogues of (S)-α-methyl-3-carboxyphenylalanine

Two analogues 2, 3 of (S)-α-methyl-3-carboxylphenylalanine 1 were synthesized to test their activity for metabotropic glutamate receptors (mGluRs). Both compounds 2 and 3 were inactive as antagonist for mGluRs, but 2 showed weak agonistic activity for GluR6 in contrast to that reported by Kemp and co-workers.