Synthesis and in vitro evaluation of fluorinated diphenyloxide derivatives and sulfur analogs as serotonin transporter ligands.

As the serotonin transporter (SERT) is involved in several neurodegenerative and psychiatric disorders; radiopharmaceuticals to image the SERT by PET would be valuable in studying these diseases. To this end we synthesized diphenyloxide derivatives and sulfide analogs, as new tracers, incorporating a fluorine or oxyalkyl fluorinated group on 4' or 5'-position on phenyl ring B. Three of these exhibited good to high in vitro affinity (7<K(i)<8 nM) and selectivity for the SERT over the other monoamine transporters.