CNS-1307

A series of N,N'-disubstituted acetamidines RN:CMeNHR' (R, R' are o-tolyl or cycloalkyls) was prepared as mammalian brain sigma receptor ligands (as potential antipsychotics).The in vitro binding affinities of seven representative ligands were measured using guinea pig brain membrane suspensions.N-1-adamantyl-N'-o-tolylacetamidine is the most potent ligand in the series [IC₅₀ = 6 nM vs. [³H]-DTG (N,N'-di-o-tolylguanidine)].All ligands showed low affinity toward the PCP (NMDA receptor ion-channel) site.