Description

Rac n-Desmethyl Mephenytoin-Deuterated CAS NO 119458-27-4 is a stable isotope-labeled analog of a key mephenytoin metabolite, specifically designed for use as an internal standard in quantitative bioanalytical methods. This compound is critical for ensuring the accuracy and precision of pharmacokinetic and metabolic studies, particularly those involving the cytochrome P450 2C19 (CYP2C19) enzyme pathway. It is an essential tool for pharmaceutical R&D laboratories, clinical research organizations, and forensic toxicology labs engaged in drug metabolism and therapeutic drug monitoring.

Application

• Internal Standard for LC-MS/MS: Primary use as a quantitative internal standard in liquid chromatography-tandem mass spectrometry (LC-MS/MS) assays for mephenytoin and its metabolites in biological matrices.
• CYP2C19 Phenotyping Studies: Enables precise measurement of the S-/R-mephenytoin urinary ratio, a gold-standard metric for determining an individual's CYP2C19 metabolic phenotype (poor, intermediate, extensive, or ultrarapid metabolizer).
• Drug-Drug Interaction (DDI) Research: Used in clinical studies to assess the inhibitory or inductive effects of new drug candidates on the CYP2C19 enzyme.
• Pharmacokinetic (PK) and Bioequivalence Studies: Provides reliable quantification of mephenytoin concentration in plasma and urine for robust PK parameter calculation.
• Forensic and Clinical Toxicology: Supports accurate identification and quantification of mephenytoin in complex samples for diagnostic or legal purposes.
• Method Development and Validation: Serves as a critical reference material for developing, optimizing, and validating new analytical methods in compliance with FDA, EMA, or ICH guidelines.

Basic Information

Item	Detail
Product Name	Rac n-Desmethyl Mephenytoin-Deuterated
CAS No.	119458-27-4
Molecular Formula	C11H10D2N2O2
Molecular Weight	~ 204.23 g/mol
Synonyms	rac 5-Ethyl-5-phenyl-2,4-imidazolidinedione-d2; (±)-5-Ethyl-5-phenylhydantoin-d2; Nor-Mephenytoin-d2; n-Desmethyl Mephenytoin-d2; 5-Ethyl-5-phenyl-2,4-imidazolidinedione-3,3-d2; Deuterated Nor-Mephenytoin; rac 3,3-Dideuterio-5-ethyl-5-phenylimidazolidine-2,4-dione; Internal Standard for Mephenytoin Assay
EINECS	Contact for details

Quality Control

Every batch of Rac n-Desmethyl Mephenytoin-Deuterated is manufactured and tested under strict quality management systems. We guarantee high chemical and isotopic purity to meet the exacting demands of quantitative bioanalysis. Comprehensive testing includes identity confirmation, assay, isotopic enrichment (D%), and control of related substances and residual solvents. A detailed Certificate of Analysis (COA) is provided with each shipment, documenting compliance with our rigorous specifications.

Storage

Preserve in a tightly closed container, protected from light. Store at controlled room temperature (15-25°C) or as indicated on the label. This material is hygroscopic (moisture-sensitive). Keep the container tightly sealed in a dry environment to prevent degradation. For long-term storage, consider storing under inert atmosphere.

Specification

Item	Specification
Appearance	White to off-white powder
Identification (IR)	Conforms to structure
Identification (MS)	Conforms to structure
Purity (HPLC)	≥ 98.0%
Isotopic Purity (D%)	≥ 98.0 atom % D
Chemical Purity (NMR)	Conforms
Water Content (KF)	≤ 0.5%
Residual Solvents (GC)	Complies with ICH limits

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