Description

Indometacin Impurity 18 is a specified impurity of the non-steroidal anti-inflammatory drug (NSAID) Indomethacin, identified by the CAS registry number 75511-23-8. This compound is critical for pharmaceutical research and development, serving as a key reference standard in the analytical characterization and quality control of Indomethacin active pharmaceutical ingredients (APIs) and finished drug products. It is primarily required by analytical chemists, quality assurance professionals, and regulatory affairs specialists within the pharmaceutical and contract research organization (CRO) sectors to ensure drug safety, efficacy, and regulatory compliance.

Application

• Pharmaceutical Reference Standard: Used as a certified reference material (CRM) for the identification and quantification of Indometacin Impurity 18 in drug substance and drug product testing.
• Method Development and Validation: Essential for developing, optimizing, and validating stability-indicating analytical methods, such as HPLC and UPLC, for Indomethacin.
• Quality Control & Assurance: Employed in routine batch release testing to monitor impurity profiles and ensure compliance with pharmacopeial specifications (e.g., USP, EP, ICH Q3A/B).
• Stability Studies: Acts as a marker in forced degradation and long-term stability studies to understand the degradation pathways of Indomethacin.
• Regulatory Submissions: Provides necessary data for regulatory filings (e.g., ANDA, NDA, CTA) to demonstrate thorough impurity characterization and control.
• Research and Development: Utilized in synthetic chemistry research to study the formation and mitigation of this specific impurity during the API manufacturing process.

Basic Information

Product Name	Indometacin Impurity 18
CAS No.	75511-23-8
Molecular Formula	C19H16ClNO4
Molecular Weight	357.79 g/mol
Synonyms	1-(4-Chlorobenzoyl)-5-methoxy-2-methyl-1H-indole-3-acetic acid; Indomethacin Impurity 18; Indomethacin Related Compound 18; 5-Methoxy-2-methyl-1-(4-chlorobenzoyl)indol-3-ylacetic acid; 3-Acetyl-1-(4-chlorobenzoyl)-5-methoxy-2-methylindole (related); Indometacin EP Impurity C; Indomethacin USP Related Compound C
EINECS	Contact for details

Quality Control

Every batch of Indometacin Impurity 18 is manufactured and analyzed under strict quality management systems. Our products undergo rigorous identity, purity, and assay testing using advanced techniques like HPLC, GC, and NMR to ensure compliance with pharmacopeial and customer-specific standards. A comprehensive Certificate of Analysis (COA) is provided with each shipment, detailing batch-specific results for purity, related substances, residual solvents, and other critical parameters.

Storage

Preserve in a tightly closed container, protected from light. Store in a cool, dry place at a controlled room temperature (15-25°C). This material is hygroscopic (moisture-sensitive); ensure the container is sealed tightly after each use to prevent absorption of atmospheric moisture. For long-term storage, consider storing under an inert atmosphere.

Specification

Item	Specification
Appearance	White to off-white powder
Identification (IR)	Conforms to structure
Identification (HPLC)	Retention time matches reference standard
Purity (HPLC)	≥ 98.0%
Related Substances (HPLC)	Total impurities ≤ 2.0% Any single unknown impurity ≤ 0.5%
Water Content (KF)	≤ 0.5% w/w
Residual Solvents (GC)	Complies with ICH Q3C

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