Description

S-p-Methylbenzyl-L-Cysteine is a high-purity, non-proteinogenic amino acid derivative featuring a chiral center and a protected thiol group. This compound is a critical chiral building block and intermediate in the synthesis of complex pharmaceuticals and bioactive peptides. It is primarily utilized by research institutions and manufacturers in the pharmaceutical, biotechnology, and fine chemical sectors for developing novel therapeutic agents and advanced materials.

Application

• Pharmaceutical Intermediate: A key chiral synthon in the asymmetric synthesis of active pharmaceutical ingredients (APIs), particularly for drugs targeting cardiovascular and neurological disorders.
• Peptide Synthesis: Used as a protected cysteine analog in solid-phase and solution-phase peptide synthesis to introduce specific structural motifs or for conjugation chemistry.
• Bioconjugation & Linker Chemistry: Serves as a versatile building block for creating drug-linker systems in antibody-drug conjugates (ADCs) and other targeted therapies.
• Biochemical Research: Employed as a standard or reagent in enzymatic studies, protein engineering, and investigations into redox biology and thiol-disulfide exchange mechanisms.
• Catalyst & Ligand Preparation: Used to synthesize chiral ligands for asymmetric catalysis or to functionalize surfaces and materials for specialized applications.

Basic Information

Product Name	S-p-Methylbenzyl-L-Cysteine
CAS No.	42294-52-0
Molecular Formula	C11H15NO2S
Molecular Weight	225.31 g/mol
Synonyms	L-Cysteine, S-[(4-methylphenyl)methyl]-; (R)-2-Amino-3-((4-methylbenzyl)thio)propanoic acid; S-(4-Methylbenzyl)-L-cysteine; p-Methylbenzyl-L-cysteine; (2R)-2-Amino-3-[(4-methylphenyl)methylsulfanyl]propanoic acid; S-p-Methylbenzylcysteine; NSC 334906
EINECS	Contact for details

Quality Control

Our S-p-Methylbenzyl-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 stringent specifications for pharmaceutical R&D and production. A Certificate of Analysis (COA) detailing identity, purity, and impurity profiles is provided with every shipment to guarantee traceability and batch-to-batch consistency.

Storage

Preserve in a tightly closed container, protected from light. Store in a cool, dry place at 15-25°C. This material is hygroscopic (moisture-sensitive) and should be handled in a dry environment to prevent degradation. For long-term storage, consider desiccant or inert atmosphere.

Specification

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

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