Description

Clemizole CAS NO 442-52-4 is a selective histamine H1 receptor antagonist belonging to the benzimidazole class of compounds. This high-purity pharmaceutical intermediate is critical for ensuring the efficacy and safety of downstream active pharmaceutical ingredients (APIs). It is primarily utilized by research institutions and manufacturers in the pharmaceutical industry for the development and production of antihistamine medications and other therapeutic agents.

Application

• Key intermediate in the synthesis of advanced antihistamine pharmaceutical compounds.
• Research and development (R&D) of new chemical entities (NCEs) targeting histamine-mediated pathways.
• Production of reference standards for analytical method development and quality control laboratories.
• Building block for medicinal chemistry studies exploring structure-activity relationships (SAR).
• Used in biochemical research to study histamine receptor function and inhibition.

Basic Information

Product Name	Clemizole
CAS No.	442-52-4
Molecular Formula	C19H21ClN2
Molecular Weight	312.84 g/mol
Synonyms	1-(4-Chlorobenzyl)-2-(1-pyrrolidinylmethyl)benzimidazole; Allercur; Histacur; NSC 113093; Pyrrobutamine; Clemizole Hydrochloride (salt form); 1-[(4-Chlorophenyl)methyl]-2-(pyrrolidin-1-ylmethyl)-1H-benzimidazole
EINECS	207-143-5

Quality Control

Our Clemizole is manufactured under strict quality management systems. Each batch undergoes comprehensive analytical testing to ensure identity, purity, and consistency, meeting the stringent requirements for pharmaceutical intermediates. Certificates of Analysis (COA) detailing specifications and test results are provided with every shipment.

Storage

Preserve in a tightly closed container, protected from light. Store in a cool, dry, and well-ventilated place at a controlled room temperature (15-25°C). Due to its hygroscopic (moisture-sensitive) nature, the container must be kept tightly sealed to prevent degradation from atmospheric moisture.

Specification

Item	Specification
Appearance	White to off-white crystalline powder
Identification (IR)	Conforms to reference spectrum
Identification (HPLC)	Retention time corresponds to reference standard
Assay (HPLC)	≥98.0%
Related Substances (HPLC)	Total impurities ≤2.0% Any single impurity ≤0.5%
Loss on Drying	≤1.0%
Residue on Ignition	≤0.1%

Note: Specifications can be tailored. Please contact us for the detailed technical data sheet of a specific grade.