The cardio- and hemodynamic effects of the derivative of aza-15-crown-5 was studied in acute experiments on anesthetized (ethaminal sodium, 50 mg/kg) cats. At intravenous administration the compound was found to induce hypotension, to dilate arterial vessels, to exert negative ino- and chronotropic effects, to decrease the cardiac output. The pharmacological analysis suggests that the mechanism of the cardiotropic action of the compound is due to its intervention in calcium ion metabolism.