Synthesis and dopaminergic activity of heterocyclic analogues of 5,6-dihydroxy-2-aminotetralins

The heterocyclic analogues of 5,6-dihydroxy-2-aminotetralins (6) were synthesized and their in vitro dopaminergic activity was compared to that of (−)-DP-5,6-ADTN and the novel potent agonist Z12571. The results show that changing the cathecol ring for a heterocycle decreases the D1-like activity of the target molecules 6. However, the D2-like activity of tetrahydroquinoline (6j) was comparable to that of (−)-DP-5,6-ADTN. Scheme 1. i, NaOH, H2O, CH2Cl2. ii, SOCl2, DMF, CH2Cl2. iii, TEA, DMF, CH2Cl2. iv, (CH3)2S•BH3 (DIBAL-H for 11d). v, 48% HBr.