C1-Methylated 5-hydroxy-2-(dipropylamino)tetralins: central dopamine-receptor stimulating activity

Abstract
C1-Methylated derivatives of the potent dopaminergic agonist 5-hydroxy-2-(di-n-propylamino)tetralin (6) were synthesized and tested for central dopamine (DA) receptor stimulating activity, by using biochemical and behavioral tests in rats. Both cis- and trans-5-hydroxy-1-methyl-2-(di-n-propylamino)tetralin (4 and 3) may be classified as central DA-receptor agonists, albeit of lower potency than 6. Both 4 and 3 display DA-autoreceptor stimulation capacity. Only 1 of the isomers, trans-3 is able to elicit clear-cut postsynaptic DA receptor agonist actions at larger doses. 5-Hydroxy-1,1-dimethyl-2-(n-propylamino)tetralin was inactive.