Ebastine

Description

Ebastine is a new once-daily histamine Hl-receptor antagonist with no sedative effects or autonomic impairment at therapeutic doses. It is reported to be effective in the treatment of hay fever, perennial rhinitis, and uticaria. Ebastine's antihistamine activity is attributed to its carboxylic acid metabolite carebastine.

Chemical properties

White to Off-White Powder

Originator

Almirall (Spain)

The Uses of Ebastine

Ebastine is a second-generation H1 receptor antagonist that is indicated mainly for allergic rhinitis and chronic idiopathic urticaria. It is available in 10 and 20 mg tablets and as fast-dissolving tablets, as well as in pediatric syrup. It has a recommended flexible daily dose of 10 or 20 mg, depending on disease severity.

The Uses of Ebastine

A nonsedating type histamine H1-receptor antagonist. Antihistaminic

Definition

ChEBI: Ebastine is an organic molecular entity.

Background

Ebastine is under investigation for the treatment of Irritable Bowel Syndrome (IBS). Ebastine has been investigated for the treatment of Urticaria.

What are the applications of Application

Ebastine is an antagonist of the histamine H1-receptor

Manufacturing Process

(a) A mixture of 4-hydroxypiperidine (40.4 g; 0.4 moles), p-tert-butyl-ω- chlorobutyrophenone (105 g, 0.44 moles), sodium bicarbonate (67.2 g; 0.8 moles) and a crystal of potassium iodide in methyl isobutyl ketone (1 liter) was boiled under reflux for 24 hours. After cooling, the reaction mixture waswashed with water, dried (Na2SO4) and the solvent removed in vacuum. The residue was salified with the stoichiometric amount of fumaric acid in a mixture of acetone and ethanol to give 1-[3-(4-tert-butylbenzoyl)propyl]-4- hydroxypiperidine fumarate (148 g), melting point 163-165°C. This compound was converted into the free base, and 1-[3-(4-tert-butylbenzoyl)propyl]-4- hydroxypiperidine was obtained and recrystallized from a mixture of diethyl ether and petroleum ether (boiling point 50-70°C). 102 g were obtained (yield 84%), melting point 63-65°C.
(b) A mixture of 1-[3-(tert-butylbenzoyl)propyl]-4-hydroxypiperidine (60.68 g; 0.2 moles) and sodium carbonate (42.4 g; 0.4 moles) in methyl isobutyl ketone (500 ml) was heated to the boiling point and a solution of diphenylmethyl bromide (49.42 g; 0.2 moles) in methyl isobutyl ketone (75 ml) was slowly added in 1.5 hours. The resulting mixture was boiled under reflux for another 12 hours, and then another solution of diphenylmethyl bromide (24.71 g; 0.1 moles) in methyl isobutyl ketone (50 ml) was added and the mixture boiled under reflux again for 12 hours. Another solution of diphenylmethyl bromide in the same quantity was added and after refluxing for 12 additional hours the reaction mixture was cooled, washed with water, dried (Na2SO4) and the solvent removed in vacuum.
The residual oil was treated with the stoichiometric amount of fumaric acid in ethanol and 4-diphenylmethoxy-1-[3-(4-tert-butylbenzoyl)propyl]piperidine fumarate crystallized. After recrystallisation from ethanol the pure compound was obtained (88 g; yield 75%), melting point 197-198°C.

brand name

Kestine (Rhone-Poulenc Rorer);Ebastel.

Therapeutic Function

Antihistaminic, Antiallergic, Calcium entry blocker

General Description

Ebastine is metabolised by cytochrome P450 3A (CYP3A4) to carebastine. It is used to treat allergic rhinitis and chronic idiopathic urticaria.

Biochem/physiol Actions

Ebastine is a non-sedating histamine H1 receptor antagonist, which inhibits allergen-induced bronchospasm in conscious guinea pigs. Unlike other compounds in this category, ebastine does not prolong the QT interval at up to five times the recommended therapeutic dose.

Metabolism