Description

n-(Acetyl-D3)-S-Benzyl-L-Cysteine is a stable isotope-labeled derivative of the amino acid cysteine, specifically deuterated on the acetyl group. This compound is critically important as a high-purity internal standard and reference material for quantitative mass spectrometry (MS) and nuclear magnetic resonance (NMR) analysis. It is primarily required by pharmaceutical R&D laboratories, contract research organizations (CROs), and analytical service providers for method development, validation, and precise quantification in pharmacokinetic, metabolomic, and proteomic studies.

Application

• Internal Standard for LC-MS/MS: Used for the accurate quantification of cysteine, cysteine-containing peptides, and related metabolites in complex biological matrices like plasma, urine, and tissue homogenates.
• Metabolic Pathway Tracing: Employed in deuterium-labeling studies to investigate sulfur amino acid metabolism, protein synthesis rates, and glutathione turnover.
• Pharmaceutical Impurity Profiling: Serves as a reference standard for identifying and quantifying process-related impurities or degradation products in cysteine-based drug substances.
• Proteomics Research: Facilitates relative and absolute quantification (AQUA) in bottom-up proteomics for studying post-translational modifications like S-benzylation or acetylation.
• Stable Isotope Dilution Assay (SIDA): A key component in highly precise analytical methods for clinical diagnostics and nutritional studies.
• NMR Spectroscopy: Provides a non-radioactive tracer for dynamic NMR studies of molecular structure and interaction.

Basic Information

Product Name	n-(Acetyl-D3)-S-Benzyl-L-Cysteine
CAS No.	201404-15-1
Molecular Formula	C₁₂H₁₂D₃NO₃S
Molecular Weight	254.33 g/mol
Synonyms	N-Acetyl-D3-S-benzyl-L-cysteine; (2R)-2-Acetamido-3-(benzylsulfanyl)propanoic-2,2,2-d3 acid; L-Cysteine, N-acetyl-3-(phenylmethyl)-, (acetyl-d3)-; S-Benzyl-N-(trideuteroacetyl)-L-cysteine; Deuterated Acylcysteine; Stable Isotope Labeled Cysteine Derivative; Internal Standard for Cysteine Analysis
EINECS	Contact for details

Quality Control

Every batch of n-(Acetyl-D3)-S-Benzyl-L-Cysteine is manufactured under controlled conditions and undergoes rigorous analytical testing to ensure identity, purity, and isotopic enrichment meet the stringent requirements for analytical reference standards. Our quality commitment includes comprehensive characterization by HPLC, MS, NMR, and chiral analysis. A detailed Certificate of Analysis (COA) is provided with each shipment, reporting batch-specific data for isotopic purity (D-enrichment), chemical purity, and specific tests.

Storage

Preserve in a tightly closed container, protected from light. Store in a cool, dry place at 2-8°C. This product is hygroscopic (moisture-sensitive). For long-term storage, consider desiccation or storage under an inert atmosphere to maintain stability and isotopic integrity.

Specification

Item	Specification
Appearance	White to off-white crystalline powder
Identification (IR)	Conforms to structure
Identification (MS)	Conforms to structure
Purity (HPLC)	≥ 98.0%
Isotopic Purity (D-enrichment)	≥ 98 atom % D
Optical Rotation	Specific range provided per COA
Water Content (KF)	≤ 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.