Description

S-(3,4-Dimethylbenzene)-L-Cysteine is a specialized chiral cysteine derivative where the thiol group is protected by a 3,4-dimethylbenzene moiety. This compound is a critical building block in pharmaceutical research and development, particularly for the synthesis of peptide-based drugs and enzyme inhibitors where precise stereochemistry is paramount. It is essential for researchers and manufacturers in the pharmaceutical, biotechnology, and fine chemical sectors requiring high-purity, custom amino acid derivatives for advanced applications.

Application

• Pharmaceutical Intermediate: A key chiral synthon for the development of novel active pharmaceutical ingredients (APIs), especially in oncology and metabolic disease research.
• Peptide Synthesis: Used in solid-phase and solution-phase peptide synthesis to introduce a protected cysteine residue with enhanced stability.
• Bioconjugation & Protein Engineering: Serves as a handle for site-specific modification of proteins and antibodies in bioconjugation strategies.
• Enzyme Inhibitor Development: Employed in the design and synthesis of cysteine protease inhibitors and other enzyme-targeted therapeutics.
• Chemical Biology Research: A valuable tool compound for studying protein function, folding, and disulfide bond formation in biochemical assays.
• Fine Chemical Synthesis: Used as a precursor for the synthesis of more complex, sulfur-containing chiral molecules in asymmetric synthesis.

Basic Information

Product Name	S-(3,4-Dimethylbenzene)-L-Cysteine
CAS No.	1331904-81-4
Molecular Formula	C11H15NO2S
Molecular Weight	225.31 g/mol
Synonyms	L-Cysteine, S-(3,4-dimethylphenyl)-; (2R)-2-Amino-3-[(3,4-dimethylphenyl)sulfanyl]propanoic acid; S-(3,4-Dimethylphenyl)-L-cysteine; S-(3,4-Xylyl)-L-cysteine; 3,4-Dimethylbenzyl-L-cysteine thioether; 3,4-Dimethylbenzylcysteine
EINECS	Contact for details

Quality Control

Our S-(3,4-Dimethylbenzene)-L-Cysteine is manufactured under strict quality management systems. Each batch undergoes comprehensive analytical testing, including chiral purity verification by HPLC, to ensure it meets the high standards required for research and development. A detailed Certificate of Analysis (COA) is provided with every shipment, confirming identity, purity, and compliance with customer specifications.

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 product is hygroscopic (moisture-sensitive) and should be handled in a dry environment to prevent degradation.

Specification

Item	Specification
Appearance	White to off-white powder
Identification (IR)	Conforms to structure
Assay (HPLC)	≥ 98.0%
Chiral Purity (HPLC)	≥ 99.0% (L-isomer)
Loss on Drying	≤ 1.0%
Residue on Ignition	≤ 0.1%
Heavy Metals (as Pb)	≤ 10 ppm

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