Description

L-Cysteine, S-(2-Bromoethyl)- is a specialized, high-value cysteine derivative where the thiol group is functionalized with a 2-bromoethyl moiety. This modification introduces a reactive alkyl halide handle, making it a crucial bifunctional building block for synthesizing complex molecules and conjugates. It is primarily utilized by research institutions and industrial R&D departments in the pharmaceutical, biotechnology, and advanced materials sectors for applications requiring precise molecular tethering.

Application

• Pharmaceutical Intermediate: Key precursor in the synthesis of novel drug candidates, particularly those targeting cysteine proteases or requiring thioether linkage.
• Bioconjugation Reagent: Used for site-specific modification of peptides, proteins, and antibodies to create stable thioether bonds for drug delivery systems and diagnostic probes.
• Chemical Biology Probe: Essential tool for studying protein function and interactions through covalent labeling and cross-linking experiments.
• Peptide Synthesis: Serves as a protected and activated cysteine derivative in solid-phase and solution-phase peptide synthesis.
• Material Science: Building block for creating functionalized surfaces, polymers, and dendrimers with specific biorecognition or adhesion properties.
• Ligand Development: Used in the preparation of chelating agents and catalysts for asymmetric synthesis and metal ion binding.

Basic Information

Product Name	L-Cysteine, S-(2-Bromoethyl)-
CAS No.	88169-61-3
Molecular Formula	C5H10BrNO2S
Molecular Weight	228.11 g/mol
Synonyms	S-(2-Bromoethyl)-L-cysteine; (R)-2-Amino-3-((2-bromoethyl)thio)propanoic acid; L-Cysteine S-(β-bromoethyl) ether; 2-Bromoethyl L-cysteinyl ether; NSC 113928; 2-Amino-3-[(2-bromoethyl)sulfanyl]propanoic acid; (2R)-2-Amino-3-[(2-bromoethyl)sulfanyl]propanoic acid
EINECS	Contact for details

Quality Control

Our L-Cysteine, S-(2-Bromoethyl)- is manufactured under strict quality systems. Each batch undergoes comprehensive analytical testing, including HPLC for purity and chiral integrity, NMR for structural confirmation, and residual solvent analysis. We provide full traceability and detailed Certificates of Analysis (COA) to support your research and regulatory requirements. Specifications can be aligned with cGMP standards for advanced pharmaceutical applications upon request.

Storage

Preserve in a tightly closed container, protected from light. Store in a cool, dry place at 2-8°C (refrigerated) or as specified on the label or COA. This product is hygroscopic (moisture-sensitive); ensure the container is sealed under an inert atmosphere after each use to maintain stability and prevent degradation.

Specification

Item	Specification
Appearance	White to off-white crystalline powder
Identification (IR)	Conforms to structure
Assay (HPLC)	≥ 98.0%
Chiral Purity (HPLC)	≥ 99.0% (L-isomer)
Water Content (KF)	≤ 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.