Description

Sildenafil Impurity 18 is a designated pharmaceutical reference standard used for analytical and quality control purposes. This compound is critical for ensuring the purity, safety, and efficacy of the active pharmaceutical ingredient (API) Sildenafil Citrate and its related drug products. It is primarily required by pharmaceutical manufacturers, analytical laboratories, and regulatory bodies for method development, validation, and batch release testing. The availability of a well-characterized impurity standard is essential for compliance with stringent global pharmacopeial requirements.

Application

• Primary use as a certified reference standard for the identification and quantification of Sildenafil Impurity 18 in Sildenafil API and finished dosage forms.
• Critical component in analytical method development and validation (HPLC, UPLC, LC-MS) for impurity profiling.
• Essential for quality control and batch release testing in pharmaceutical manufacturing to meet ICH Q3A/B guidelines.
• Used in stability studies to monitor impurity formation under various stress conditions.
• Serves as a system suitability standard in regulatory submissions to agencies like the US FDA and EMA.
• Valuable for research and development of Sildenafil-based pharmaceuticals and related synthetic pathways.

Basic Information

Product Name	Sildenafil Impurity 18
CAS No.	2196244-90-1
Molecular Formula	Contact for details
Molecular Weight	Contact for details
Synonyms	Sildenafil Related Compound 18; Sildenafil EP Impurity 18; Sildenafil USP Impurity 18; Sildenafil Process Impurity; 1-[[3-(6,7-Dihydro-1-methyl-7-oxo-3-propyl-1H-pyrazolo[4,3-d]pyrimidin-5-yl)-4-ethoxyphenyl]sulfonyl]-4-methylpiperazine (proposed); Sildenafil Degradant; Analytical Reference Standard for Sildenafil
EINECS	Contact for details

Quality Control

Every batch of Sildenafil Impurity 18 is manufactured and handled under strict quality management systems. The product undergoes comprehensive analytical testing, including chromatographic purity (HPLC), spectroscopic identification (IR, NMR, MS), and residual solvent analysis to ensure it meets the highest standards for pharmaceutical reference materials. A detailed Certificate of Analysis (COA) with batch-specific data, including purity assignment and traceability, is provided with each shipment to support regulatory compliance.

Storage

Preserve in a tightly closed container, protected from light. Store at controlled room temperature, typically between 15-25°C (59-77°F). The container should be kept in a dry environment to prevent moisture uptake. For long-term storage, consider storing under inert atmosphere.

Specification

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

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