Chemical Properties
White Crystalline Solid
Originator
Kerlone,Carriere,France,1983
Uses
Cardioselective 1-adrenergic blocker. An antihypertensive; antiglaucoma
Uses
Cardioselective β1-adrenergic blocker. An antihypertensive; antiglaucoma.
Definition
ChEBI: A propanolamine that is 3-aminopropane-1,2-diol in which the hydrogen of the primary hydoxy is substituted by a 4-[2-(cyclopropylmethoxy)ethyl]phenyl group and one of the hydrogens attached to the amino group is substituted by isopropyl. It is a selective
beta1-receptor blocker and is used in the treatment of glaucoma as well as hypertension, arrhythmias, and coronary heart disease. It is also used to reduce non-fatal cardiac events in patients with heart failure.
Manufacturing Process
(1) 1 g of sodium hydroxide pellets (0.025 mol) is added to a suspension of
3.8 g of 4-[2-(cyclopropylmethoxy)-ethyl]-phenol in 30 ml of water. When the
solution becomes homogenous, 2.3 ml of epichlorohydrin are added and the
mixture is stirred for 8 hours. It is then extracted with ether and the extract is
washed with water, dried over sodium sulfate and evaporated to dryness. The
compound is purified by passing it over a silica column. 2.4 g of 1-[4-[2-
(cyclopropylmethoxy)ethyl]-phenoxy]-2,3-epoxy-propane are thus obtained.
(2) 4.9 g of the preceding compound (0.02 mol) are condensed with 25 ml of
isopropylamine by contact for 8 hours at ambient temperature and then by
heating for 48 hours at the reflux temperature. After evaporation to dryness,
the compound obtained is crystallized from petroleum ether. 5 g (yield 80%)
of 2-[[4-(2-cyclopropylmethoxy)-ethyl]-phenoxy]-3-isopropylaminopropan-2-ol
are thus obtained, melting point 70° to 72°C.
The hydrochloride is prepared by dissolving the base in the minimum amount
of acetone and adding a solution of hydrochloric acid in ether until the pH is
acid. The hydrochloride which has precipitated is filtered off and is
recrystallized twice from acetone, melting point 116°C.
Brand name
Betoptic (Alcon); Kerlone (Sanofi Aventis).
Therapeutic Function
Beta-adrenergic blocker
Biological Activity
betaxolol is a cardioselective beta-adrenergic receptor blocking agent. betaxolol (5 mg/kg via i.p. injection) was administered at 24 and then 44 h following the final chronic cocaine administration. animals treated with betaxolol during cocaine withdrawal
Veterinary Drugs and Treatments
Betaxolol HCl is a specific Beta1 adrenergic blocking agent which
reduces aqueous humor production by decreasing cyclic-AMP
synthesis in the ciliary body. This drug is a suitable substitute for
timolol and because of its specific Beta1 activity, might be a first
choice Beta blocking agent for patients with concurrent respiratory
disease. Either levobunolol HCl or betaxolol HCl would be the first
choice Beta blocking agent in a feline patient with glaucoma and
asthma, although a topical carbonic anhydrates inhibitor should be
considered before a Beta blocking agent in this situation. Betaxolol
and the other Beta blockers should be used with caution in patients
with cardiac disease.
Metabolism
Absorption of an oral dose of betaxolol (Kerlone,
Betoptic) is almost complete. The drug is subject to a
slight first-pass effect such that the absolute bioavailability
of the drug is about 90%.Approximately 50% of
administered betaxolol binds to plasma proteins, and its
plasma half-life is about 20 hours; it is suitable for dosing
once per day.The primary route of elimination is by
liver metabolism, with only 15% of unchanged drug being
excreted.
