Quinapril-d5 is intended for use as an internal standard for the quantification of quinapril by GC- or LC-MS. Quinapril is a prodrug form of the angiotensinconvertingenzyme (ACE) inhibitor quinaprilat. In vivo, quinapril reduces mean arterial pressure in renal hypertensive and spontaneously hypertensive rats. It inhibits angiotensin I-induced pressor responses in normotensive rats and dogs. Quinapril prevents left ventricular heart failure in CHF 14.6 cardiomyopathic hamsters. Formulations containing quinapril have been used in the treatment of hypertension, heart failure, and diabetic nephropathy.
Cilazapril, also known as Ro 31 2848, is a potent ACE inhibitor used for hypertension. Cilazapril is a prodrug that is hydrolyzed after absorption to its main metabolite cilazaprilat. Cilazapril is a monoethyl ester, which acts as an angiotensin-convertingenzyme (ACE) inhibitor. The inhibitor functions by inhibiting the ability of ACE to cleave bonds of angiotensin I and Hip-His-Leu. It is known that the diacid form of Cilazapril is more potent that enalapril at inhibiting ACE.