Description

S-tert-Butyl-L-Cysteine Hydrochloride is a protected derivative of the essential amino acid L-cysteine, where the thiol group is safeguarded by a tert-butyl moiety. This protection is crucial for its primary role as a key chiral building block and intermediate in the synthesis of complex pharmaceutical compounds, particularly peptides and active pharmaceutical ingredients (APIs). It is essential for research institutions and manufacturers in the pharmaceutical, biotechnology, and fine chemical sectors who require high-purity, stereochemically defined intermediates for drug discovery and development processes.

Application

• Pharmaceutical Intermediate: A critical chiral synthon in the synthesis of peptide-based drugs, protease inhibitors, and other bioactive molecules.
• Peptide Synthesis: Used in solid-phase and solution-phase peptide synthesis where a protected cysteine residue is required to prevent unwanted side reactions.
• Research & Development: Serves as a standard or reagent in biochemical research for studying protein structure, enzyme mechanisms, and redox biology.
• API Manufacturing: Employed as a building block in the multi-step synthesis of complex Active Pharmaceutical Ingredients (APIs).
• Asymmetric Synthesis: Utilized in catalytic asymmetric reactions to introduce chiral sulfur centers into target molecules.

Basic Information

Product Name	S-tert-Butyl-L-Cysteine Hydrochloride
CAS No.	2481-09-6
Molecular Formula	C7H16ClNO2S
Molecular Weight	213.72 g/mol
Synonyms	(R)-2-Amino-3-(tert-butylthio)propanoic acid hydrochloride; L-Cysteine, S-(1,1-dimethylethyl)-, hydrochloride; tert-Butyl-L-cysteine hydrochloride; S-tert-Butylcysteine HCl; (2R)-2-Azaniumyl-3-[(2-methylpropan-2-yl)sulfanyl]propanoate chloride
EINECS	Contact for details

Quality Control

Our S-tert-Butyl-L-Cysteine Hydrochloride is manufactured under strict quality management systems. Each batch undergoes comprehensive analytical testing, including HPLC for purity and chiral integrity, to ensure it meets the high standards required for pharmaceutical R&D and manufacturing. Certificates of Analysis (COA) detailing specific batch results are available upon request to support your quality assurance and regulatory documentation needs.

Storage

Preserve in a tightly closed container, protected from light. Store in a cool, dry place at 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 crystalline powder
Identification (IR)	Conforms to structure
Assay (HPLC)	≥98.0%
Optical Rotation	Specific range available on COA
Water Content (KF)	≤1.0%
Residue on Ignition	≤0.1%
Heavy Metals	≤20 ppm

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