Fosinopril is a phosphinic acid-containing ester prodrug that belongs to the angiotensin-converting enzyme (ACE) inhibitor class of medications. It is rapidly hydrolyzed to fosinoprilat, its principle active metabolite. Fosinoprilat inhibits ACE, the enzyme responsible for the conversion of angiotensin I (ATI) to angiotensin II (ATII). ATII regulates blood pressure and is a key component of the renin-angiotensin-aldosterone system (RAAS). Fosinopril may be used to treat mild to moderate hypertension, as an adjunct in the treatment of congestive heart failure, and to slow the rate of progression of renal disease in hypertensive individuals with diabetes mellitus and microalbuminuria or overt nephropathy.

Quinapril is the hydrochloride salt of quinapril, the ethyl ester of a non-sulfhydryl, angiotensin-converting enzyme (ACE) inhibitor, quinaprilat. Quinapril hydrochloride is a white to off-white amorphous powder that is freely soluble in aqueous solvents. Quinapril is indicated for the treatment of high blood pressure (hypertension) and as adjunctive therapy in the management of heart failure. It may be used for the treatment of hypertension by itself or in combination with thiazide diuretics, and with diuretics and digoxin for heart failure.

BENAZEPRIL, (±)- is an impurity referred to as Related Compound B, which is a diastereomer of benazepril, an ACE inhibitor, under the brand name Lotensin used primarily in treatment of hypertension, congestive heart failure, and heart attacks, and also in preventing the renal and retinal complications of diabetes. BENAZEPRIL, (±)- is used as USP Reference Standard.

Quinapril is the hydrochloride salt of quinapril, the ethyl ester of a non-sulfhydryl, angiotensin-converting enzyme (ACE) inhibitor, quinaprilat. Quinapril hydrochloride is a white to off-white amorphous powder that is freely soluble in aqueous solvents. Quinapril is indicated for the treatment of high blood pressure (hypertension) and as adjunctive therapy in the management of heart failure. It may be used for the treatment of hypertension by itself or in combination with thiazide diuretics, and with diuretics and digoxin for heart failure.

BENAZEPRIL, (±)- is an impurity referred to as Related Compound B, which is a diastereomer of benazepril, an ACE inhibitor, under the brand name Lotensin used primarily in treatment of hypertension, congestive heart failure, and heart attacks, and also in preventing the renal and retinal complications of diabetes. BENAZEPRIL, (±)- is used as USP Reference Standard.

BENAZEPRIL, (±)- is an impurity referred to as Related Compound B, which is a diastereomer of benazepril, an ACE inhibitor, under the brand name Lotensin used primarily in treatment of hypertension, congestive heart failure, and heart attacks, and also in preventing the renal and retinal complications of diabetes. BENAZEPRIL, (±)- is used as USP Reference Standard.

Fosinopril is a phosphinic acid-containing ester prodrug that belongs to the angiotensin-converting enzyme (ACE) inhibitor class of medications. It is rapidly hydrolyzed to fosinoprilat, its principle active metabolite. Fosinoprilat inhibits ACE, the enzyme responsible for the conversion of angiotensin I (ATI) to angiotensin II (ATII). ATII regulates blood pressure and is a key component of the renin-angiotensin-aldosterone system (RAAS). Fosinopril may be used to treat mild to moderate hypertension, as an adjunct in the treatment of congestive heart failure, and to slow the rate of progression of renal disease in hypertensive individuals with diabetes mellitus and microalbuminuria or overt nephropathy.

Quinapril is the hydrochloride salt of quinapril, the ethyl ester of a non-sulfhydryl, angiotensin-converting enzyme (ACE) inhibitor, quinaprilat. Quinapril hydrochloride is a white to off-white amorphous powder that is freely soluble in aqueous solvents. Quinapril is indicated for the treatment of high blood pressure (hypertension) and as adjunctive therapy in the management of heart failure. It may be used for the treatment of hypertension by itself or in combination with thiazide diuretics, and with diuretics and digoxin for heart failure.

Ramipril (sold under the brand name Altace ) is a prodrug belonging to the angiotensin-converting enzyme (ACE) inhibitors. It is metabolized to ramiprilat in the liver and, to a lesser extent, kidneys. Ramiprilat is a potent, competitive inhibitor of ACE, the enzyme responsible for the conversion of angiotensin I (ATI) to angiotensin II (ATII). ATII regulates blood pressure and is a key component of the renin-angiotensin-aldosterone system (RAAS). Ramipril is indicated for the treatment of hypertension, to lower blood pressure; also used to reduce the risk of myocardial infarction, stroke, or death from cardiovascular causes; in addition, this drug is used to reduce the rate of death, myocardial infarction and stroke in individuals at high risk of cardiovascular events.

Lisinopril is a potent, competitive inhibitor of angiotensin-converting enzyme (ACE). Lisinopril is marketed under the brand name ZESTRIL. ZESTRIL is indicated for the treatment of hypertension. It may be used alone as initial therapy or concomitantly with other classes of antihypertensive agents. It is also indicated as adjunctive therapy in the management of heart failure in patients who are not responding adequately to diuretics and digitalis. Lisinopril inhibits angiotensin-converting enzyme (ACE) in human subjects and animals. ACE is a peptidyl dipeptidase that catalyzes the conversion of angiotensin I to the vasoconstrictor substance, angiotensin II. Angiotensin II also stimulates aldosterone secretion by the adrenal cortex. The beneficial effects of lisinopril in hypertension and heart failure appear to result primarily from suppression of the renin-angiotensin-aldosterone system. Inhibition of ACE results in decreased plasma angiotensin II which leads to decreased vasopressor activity and to decreased aldosterone secretion. While the mechanism through which ZESTRIL lowers blood pressure is believed to be primarily suppression of the renin-angiotensin-aldosterone system, ZESTRIL is antihypertensive even in patients with low-renin hypertension.