Synthesis of 2-(alkylamino)-5,6- and -6,7-dihydroxy-3,4-dihydroquinazolines and evaluation as potential dopamine agonists.
Based upon the known dopaminergic properties of 2-aminodihydroxy-1,2,3,4-tetrahydronaphthalenes (ADTN's), heterocyclic congeners were prepared. Several 2-(alkylamino)-5,6- and -6,7-dihydroxy-3,4-dihydroquinazolines were synthesized and tested for a dopamine-like vasodilatory action in the canine renal artery. The 6,7-disubstituted series had a weak antagonist effect against dopamine. Neither 5,6- nor 6,7-dihydroxy substitution gave dopamine agonists. Measured pKa values confirmed the expectation that the dihydroquinazolines were more basic than dopamine, one possible reason for the lack of dopamine-like action.
D000818:Animals; D055598:Chemical Phenomena; D002621:Chemistry; D004285:Dogs; D006339:Heart Rate / Q000187:drug effects; D007700:Kinetics; D008297:Male; D011799:Quinazolines / Q000138:chemical synthesis* / Q000494:pharmacology; D011954:Receptors, Dopamine / Q000187:drug effects*; D014665:Vasodilator Agents / Q000494:pharmacology
D011799:Quinazolines; D011954:Receptors, Dopamine; D014665:Vasodilator Agents