Clemastine Fumarate

Description

What is clemastine fumarate?

Clemastine fumarate is the fumaric acid salt of clemastine. An antihistamine with antimuscarinic and moderate sedative properties, it is used for the symptomatic relief of allergic conditions such as rhinitis, urticaria, conjunctivitis and in pruritic (severe itching) skin conditions. It has a role as a H1-receptor antagonist, an anti-allergic agent, a muscarinic antagonist and an antipruritic drug. It contains a clemastine. (Source: ChEBI)

Clemastine Fumarate Basic information

Product Name:	Clemastine fumarate
Synonyms:	CLEMASTINE FUMARATE; CLEMASTINE FUMARATE SALT; (+)-2-(2-((p-chloro-alpha-methyl-alpha-phenylbenzyl)oxy)ethyl)-1-methylpyrro; (+)-2-(2-((p-chloro-alpha-methyl-alpha-phenylbenzyl)oxy)ethyl)-1-methylpyrroli; (+)-lfumarate(1:1); 1-methyl-2-(2-(methyl-p-chlorodiphenylmethyloxy)ethyl)pyrrolidine; (2R)-2-[2-[(1R)-1-(4-CHLOROPHENYLETHOXY)]ETHYL]-1-METHYL-2-PYRROLIDINE FUMARATE; 2-(2-(1-(4-chlorophenyl)-1-phenylethoxy)ethyl)-1-methylpyrrolidine
CAS:	14976-57-9
MF:	C25H30ClNO5
MW:	459.96
EINECS:	239-055-2
Product Categories:	antianaphylaxis; TAVIST; Histaminergics; Antagonists; Neurotransmitters; Aromatics; Chiral Reagents; Heterocycles; Intermediates & Fine Chemicals; Pharmaceuticals
Mol File:	14976-57-9.mol

Tavist Chemical Structure

Clemastine fumarate

Tavegil Chemical Properties

Melting point	158-162°C
alpha	D21 +16.9° (methanol)
Boiling point	154°C (rough estimate)
density	1.0247 (rough estimate)
refractive index	1.5790 (estimate)
storage temp.	Store at RT
solubility	DMSO: soluble5mg/mL (clear solution; warmed)
form	powder
color	white to beige
optical activity	[α]/D +15 to +25°, c = 1 in methanol
InChIKey	PMGQWSIVQFOFOQ-YKVZVUFRSA-N
CAS DataBase Reference	14976-57-9(CAS DataBase Reference)

Agasten Usage And Synthesis

Chemical Properties	White Solid
Uses	H1 Histamine receptor antagonist. Antihistaminic.
	anti-inflammatory
	Clemastine fumarate is a selective histamine H1 receptor antagonist (Ki = 0.26 nM) that also displays high affinity for muscarinic receptors (Ki = 16 nM). It has also recently been identified as a positive allosteric modulator of P2X7 receptor signaling. Clemastine fumarate has long been used to inhibit histamine-induced bronchoconstriction in asthma and airway hyperresponsive studies.
Definition	ChEBI: The fumaric acid salt of clemastine. An antihistamine with antimuscarinic and moderate sedative properties, it is used for the symptomatic relief of allergic conditions such as rhinitis, urticaria, conjunctivitis and in pruritic (severe itching) skin condi ions.
Manufacturing Process	9.9 g of α-methyl-p-chlorobenzhydrol are added to a suspension of 2.3 g of powdered sodamide in 30 cc of benzene. Subsequently 7.4 g of Nmethylpyrrolidyl-(2)-ethyl chloride are added and the solution is heated to the boil at reflux for 20 hours. Then shaking is first effected with water and then 4 times each time with 25 cc of 2 N hydrochloric acid. The acid extracts are made alkaline with potassium hydroxide solution while cooling strongly, and the precipitated oil is extracted with ether. After drying of the ethereal solution over potassium carbonate, the solvent is evaporated and the residue is fractionally distilled in a high vacuum, whereby N-methyl-2-[2′-(α-methyl-pchlorobenzhydryloxy)-ethyl]-pyrrolidine boils over at 154°C/0.02 mm Hg. The base is converted to the fumarate by reaction with fumaric acid.
Therapeutic Function	Antihistaminic