High affinity, selective dopamine D1-like receptor agonist. Ki values are 3.2, 3.1, 186, 66, 335, 1167, 1251 and 1385 nM at recombinant D1, D5, D2, D3, D4, 5-HT2A, α1A and α1B receptors respectively. Stimulates adenylyl cyclase (EC50 = 65 nM) but not phosphoinositide hydrolysis. Induces extreme arousal and hyperlocomotion following subcutaneous administration in monkeys.