Synthesis and dopamine antagonist activity of 2-thioether derivatives of the ergoline ring system.

A series of 2-thioether derivatives of a number of clavine alkaloid (ergoline) ring systems have been synthesized and tested for dopamine antagonist activity. Of the compounds tested 2-(methylthio)-agroclavine (8,9-didehydro-6,8-dimethyl-2-(methylthio)ergoline) (6) was the most potent and had a profile of activity in animal models indicative of potential antipsychotic activity. The synthesis and biological activity of a number of metabolites of 6, including the 13-hydroxy derivative, are also reported.