Synthesis and dopamine receptor affinities of 6-amino-5,6,7,8-tetrahydroquinoline derivatives

Some N,N-dialkyl derivatives of 6-amino-5,6,7,8-tetrahydroquinoline were synthesized. The affinity of new compounds for dopamine binding sites was measured in a test involving displacement of [ 3H]SCH 23390 (D-1 selective) and [ 3H]spiperone (D-2 selective) from homogenized rat striatal tissue. While no compound was effective in displacing [ 3H]SCH 23390, in the binding assays on the D-2 receptor all tetrahydroquinolines displaced [ 3H]spiperone from specific binding sites, the compounds with a N-n-propyl-N-phenylethylamino group or N,N-di n-propylamino group being the most potent.