Synthesis and in vitro evaluation of 18F-labelled S-fluoroalkyl diarylguanidines: Novel high-affinity NMDA receptor antagonists for imaging with PET

Two S-[F-18]fluoroalkylated diarylguanidines were synthesized and evaluated in vitro as potential tracers for imaging of N-methyl-D-aspartate receptors (NMDARs) with positron emission tomography (PET). [F-18]1 and [F-18]10 were synthesized by [F-18]fluoroethylation and [F-18]fluoromethylation of the thiol precursor 6, respectively. [F-18]1 is a promising candidate NMDAR PET tracer, with low nanomolar affinity for the NMDA PCP-site, high selectivity and moderate lipophilicity. (C) 2010 Elsevier Ltd. All rights reserved.