DƯỢC LÍ Goodman & Gilman's The Pharmacological Basis of Therapeutics 12th, 2010

Nonselective antagonists
311
HO
H
H
HO
O
N
N
N
OH
OH
CH 3
CH 3
OCH 2 C CH 2 NHCH
CH 3 OCH 2 CH 2 OCH 2 C CH 2 NHCH
H
CH 3
H
CH 3
METOPROLOL
PROPRANOLOL
OH
O
CH 3
CCH 2
OCH 2 C CH 2 NHCH
OH CH 3 H 2 N
H
CH 3
OCH 2 C CH 2 NHC CH 3
ATENOLOL
H
NADOLOL
O
S
CH 3 OCCH 2 CH 2 OCH 2 CHCH 2 NHCH(CH 3 ) 2
N
OH CH 3
OH
OCH 2 C CH 2 NHC CH 3 ESMOLOL
OCH 2
TIMOLOL
OH
C
H
H
CH 3
CH 3
CH 3
CH 2 NHCH
CH 3
CH 3 CH 2 CH 2 CONH
O
CCH 3
OH
ACEBUTOLOL
CHAPTER 12
ADRENERGIC AGONISTS AND ANTAGONISTS
PINDOLOL
CONH 2
OH
CH 2 CH 2 CHNHCH 2 CH
CH 3 OH
LABETALOL
Figure 12–7. Structural formulas of some β adrenergic receptor antagonists.
by the following properties: relative affinity for β 1
and
β 2
receptors, intrinsic sympathomimetic activity, blockade
of α receptors, differences in lipid solubility, capacity
to induce vasodilation, and pharmacokinetic
parameters. Some of these distinguishing characteristics
have clinical significance and help guide the appropriate
choice of a β receptor antagonist for an individual
patient.
Propranolol has equal affinity for β 1
and β 2
adrenergic receptors; thus, it is a non-selective β adrenergic
receptor antagonist. Agents such as metoprolol,
atenolol, acebutolol, bisoprolol, and esmolol have somewhat
greater affinity for β 1
than for β 2
receptors; these
are examples of β 1
-selective antagonists, even though the
selectivity is not absolute. Propranolol is a pure antagonist,
and it has no capacity to activate β receptors.