UR-AK49 is a drug used in scientific research which acts as a potent antagonist for the Neuropeptide Y / Pancreatic polypeptide receptor Y<sub>4</sub>, and also as a partial agonist at the histamine receptors H<sub>1</sub> and H<sub>2</sub>. UR-AK49 is a pure antagonist at Y<sub>4</sub> with no partial agonist effects, and although it is only slightly selective for Y<sub>4</sub> over the related Y<sub>1</sub> and Y<sub>5</sub> receptors, as the first non-peptide Y<sub>4</sub> antagonist developed UR-AK49 is expected to be useful in the study of this receptor and its role in the body.