The glutamate receptor GluR5 agonist (S)-2-amino-3-(3-hydroxy-7,8-dihydro-6H-cyclohepta[d]isoxazol-4-yl)propionic acid and the 8-methyl analogue: synthesis, molecular pharmacology, and biostructural characterization

Research output: Contribution to journalJournal articleResearchpeer-review

Rasmus Prætorius Clausen, Peter Naur, Anders Skov Kristensen, Jeremy R Greenwood, Mette Strange, Hans Bräuner-Osborne, Anders Asbjørn Jensen, Anne Sophie T Nielsen, Ulla Geneser, Lone M Ringgaard, Birgitte Nielsen, Darryl S Pickering, Lotte Brehm, Michael Gajhede, Povl Krogsgaard-Larsen, Jette Sandholm Kastrup

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-6H-cyclohepta[d]isoxazol-4-yl)propionic acid (5) is the 8-methyl analogue of (S)-2-amino-3-(3-hydroxy-7,8-dihydro-6H-cyclohepta[d]isoxazol-4-yl)propionic acid ((S)-4-AHCP, 4). Compound 5 displays an improved selectivity profile compared to 4. A versatile stereoselective synthetic route for this class of compounds is presented along with the characterization of the binding affinity of 5 to ionotropic glutamate receptors (iGluRs). Functional characterization of 5 at cloned iGluRs using a calcium imaging assay and voltage-clamp recordings show a different activation of GluR5 compared to (S)-glutamic acid (Glu), kainic acid (KA, 1), and (S)-2-amino-3-(3-hydroxy-5-tert-butyl-4-isoxazolyl)propionic acid ((S)-ATPA, 3) as previously demonstrated for 4. An X-ray crystallographic analysis of 4 and computational analyses of 4 and 5 bound to the GluR5 agonist binding domain (ABD) are presented, including a watermap analysis, which suggests that water molecules in the agonist binding site are important selectivity determinants.
Original languageEnglish
JournalJournal of Medicinal Chemistry
Volume52
Issue number15
Pages (from-to)4911-4922
ISSN0022-2623
DOIs
Publication statusPublished - 2009

Bibliographical note

Keywords: Animals; Cell Line; Crystallography, X-Ray; Drug Design; Excitatory Amino Acid Agonists; Humans; Models, Molecular; Propionic Acids; Receptors, Kainic Acid; Stereoisomerism; Structure-Activity Relationship; Xenopus laevis

ID: 14879907