Synthesis, biological activity, and absolute stereochemical assignment of NPS 1392 : A potent and stereoselective NMDA receptor antagonist

Abstract The synthesis, biological activity, and single crystal X-ray structure of NPS 1392, ( R )-(−)-3,3-bis(3-fluorophenyl)-2-methylpropan-1-amine ( 3a ), a potent, stereoselective antagonist of the NMDA receptor, are described. The NMDA receptor selectively bound the levo isomer ( 3a ) over its enantiomer ( 3b ), which prompted a rigorous absolute configuration assignment. NPS 1392 has the R configuration based on the single-crystal X-ray diffraction analysis of the hydroiodide salt of NPS 1392. This compound is a potential neuroprotective agent for use in the treatment of ischemic stroke.