Synthesis and pharmacology of (RS)-2-amino-3-(3-hydroxy-5-trifluoromethyl-4-isoxazolyl)propionic acid, a potent AMPA receptor agonist
作者:U Madsen、B Ebert、P Krogsgaard-Larsen、EHF Wong
DOI:10.1016/0223-5234(92)90181-y
日期:1992.8
Three isoxazole bioisosteres of glutamic acid derived from the specific AMPA receptor agonist (RS)-2-amino-3-(3-hydroxy-5-methyl-4-isoxazolyl)propionic acid (AMPA) were synthesized and tested electrophysiologically and in different receptor binding systems. (RS)-2-Amino-3-(3-hydroxy-5-trifluoromethyl-4-isoxazolyl)propionic acid (trifluoro-AMPA, 8) showed more potent agonist activity (EC50 2.3 muM) and lower affinity (IC50 0.08 muM) for AMPA receptors than AMPA itself (EC, 3.5 muM and IC50 0.04 muM, respectively). Like AMPA, trifluoro-AMPA (8) did not bind significantly to N-methyl-D-aspartic acid (NMDA) receptor sites, but trifluoro-AMPA (8) was more potent as an inhibitor of [H-3]kainic acid ([H-3]KAIN) binding (IC50 7.1 muM) than AMPA (IC50 32 muM). (RS)-2-Amino-3-(3-chloro-5-methyl-4-isoxazolyl)propionic acid (14), the 3-chloro analogue of AMPA, and the isomeric compound (RS)-2-amino-3-(3-chloro-4-methyl-5-isoxazolyl)propionic acid (15), did not show significant neuroexcitatory effects at or affinities for AMPA, NMDA, or KAIN receptor sites.