The design, synthesis, and pharmacological characterization of a highly potent and selective glutamate GluR5 agonist is reported.(S)-2-Amino-3-((RS)-3-hydroxy-8-methyl-7, 8-dihydro-6 H-cyclohepta [d] isoxazol-4-yl) propionic acid (5) is the 8-methyl analogue of (S)-2-amino-3- (3-hydroxy-7, 8-dihydro-6 H-cyclohepta [d] isoxazol-4-yl) propionic acid ((S)-4-AHCP, 4). Compound 5 displays an improved selectivity profile compared to 4. A versatile ...