Quinaprilat hydrochloride is an orally active non-mercapto Angiotensin Converting Enzyme ( ACE ) inhibitor, the active metabolite of Quinapril. Quinaprilat hydrochloride specifically blocks the conversion of angiotensin I to the vasoconstrictor angiotensin II and inhibits the degradation of bradykinin. Quinaprilat hydrochloride acts as anti-hypertensive agent and vasodilator.