Angiotensin-converting enzyme (
ACE) inhibitors now have an accepted place in the treatment of
hypertension and
congestive heart failure. With the discovery and development of
captopril, several other
ACE inhibitors have been synthesized and introduced for clinical use. All
ACE inhibitors bind to
zinc ions located in the active site of the ACE molecule.
ACE inhibitors can be classified according to the
ligand of the
zinc ion of ACE, into 3 different structural types: (1) the first type such as
captopril has a sulphhydryl moiety as the
ligand; (2) the second type such as
enalapril uses a carboxyl moiety as the
ligand; (3) the third type such as
fosinopril uses neither a sulphhydryl nor carboxyl group, but a
phosphinic acid as the
zinc binding moiety.
ACE inhibitors can also be classified according to the excretion route of their active moiety, into 2 different excretion route types:(1) excreated mainly through the kidney such as
captopril,
enalaprilat,
lisinopril,
benazeprilat, imdaprilat, trandraprilat, etc.; (2) excreated both in the bile and urine such as
fosinoprilat,
temocaprilat,
zofenoprilat etc.
ACE inhibitors have clinically beneficial effects not only for patients with either
hypertension or
congestive heart failure, but also can be used to prevent the progression of renal dysfunction induced by
hypertension and
diabetes mellitus.