Description

(S)-tert-Butyl 2-(tert-Butoxycarbonylamino)-4-Mercaptobutanoate is a high-purity, non-natural amino acid derivative featuring a protected thiol (mercapto) group. This compound is a critical chiral building block for the synthesis of complex peptides and peptidomimetics, enabling the introduction of disulfide bridges or thiol-mediated conjugation. It is essential for researchers and manufacturers in pharmaceutical development, particularly for creating novel therapeutic peptides, protein engineering, and bioconjugation applications. The product is supplied with a guaranteed high level of enantiomeric purity to ensure consistent and reliable results in sensitive synthetic pathways.

Application

• Pharmaceutical Intermediate: A key chiral synthon for the solid-phase and solution-phase synthesis of therapeutic peptides containing cysteine or modified cysteine analogs.
• Peptidomimetic Drug Discovery: Used to incorporate thiol functionality into peptidomimetic scaffolds for drug candidate optimization and library synthesis.
• Bioconjugation Chemistry: Serves as a precursor for generating thiol-reactive linkers used in antibody-drug conjugates (ADCs) and protein labeling.
• Disulfide Bridge Formation: The protected mercapto group is strategically used to form intramolecular or intermolecular disulfide bonds, critical for stabilizing peptide tertiary structure.
• Chemical Biology Probes: Employed in the synthesis of activity-based probes and tools for studying enzyme mechanisms involving thiol groups.
• Agrochemical Research: Potential intermediate in the development of novel bioactive compounds with specific chiral requirements.

Basic Information

Product Name	(S)-tert-Butyl 2-(tert-Butoxycarbonylamino)-4-Mercaptobutanoate
CAS No.	630108-94-0
Molecular Formula	C14H27NO4S
Molecular Weight	305.43 g/mol
Synonyms	Boc-Cys(StBu)-OtBu; (S)-2-((tert-Butoxycarbonyl)amino)-4-((tert-butyl)thio)butanoic acid tert-butyl ester; tert-Butyl (2S)-2-[(tert-butoxycarbonyl)amino]-4-sulfanylbutanoate; Boc-Cys(StBu)-O-tBu; (S)-tert-Butyl 2-(Boc-amino)-4-mercaptobutanoate; N-Boc-S-tert-butyl-L-cysteine tert-butyl ester; Fmoc-Cys(StBu)-OtBu (common related variant); L-Cysteine, N-[(1,1-dimethylethoxy)carbonyl]-S-[(1,1-dimethylethyl)-, 1,1-dimethylethyl ester
EINECS	Contact for details

Quality Control

Our (S)-tert-Butyl 2-(tert-Butoxycarbonylamino)-4-Mercaptobutanoate is manufactured under strict quality management systems. Each batch undergoes comprehensive analytical testing, including HPLC for chemical purity and chiral analysis for enantiomeric excess, to ensure it meets the high standards required for pharmaceutical R&D and production. Certificates of Analysis (COA) with detailed chromatographic data are provided for every shipment. We adhere to cGMP principles for the production of advanced pharmaceutical intermediates.

Storage

Preserve in a tightly closed container, protected from light. Store under an inert atmosphere (e.g., nitrogen or argon) at 2-8°C to prevent oxidation of the thiol group and ensure long-term stability. Keep the container in a cool, dry, and well-ventilated place. Allow the sealed container to reach room temperature before opening to minimize moisture condensation.

Specification

Item	Specification
Appearance	White to off-white crystalline powder or solid
Identification (IR)	Conforms to structure
Identification (HPLC)	Retention time matches reference standard
Purity (HPLC)	≥ 98.0%
Enantiomeric Purity (Chiral HPLC)	≥ 99.0% ee
Water Content (KF)	≤ 0.5%
Residue on Ignition	≤ 0.1%

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