Description

S-(2-Boronoethyl)-L-Cysteine Hydrochloride is a specialized organoboron derivative of the amino acid L-cysteine. This compound is of significant interest in medicinal chemistry and biochemistry as a key building block for the development of boron-containing pharmaceuticals and enzyme inhibitors. It is primarily utilized by research institutions and pharmaceutical companies engaged in the synthesis of novel therapeutic agents, particularly in areas such as proteasome inhibition and boron neutron capture therapy (BNCT).

Application

• Pharmaceutical Intermediate: A critical precursor in the synthesis of boronated drug candidates, especially proteasome inhibitors like bortezomib analogs.
• Boron Neutron Capture Therapy (BNCT): Serves as a building block for designing tumor-targeting boron carriers due to the presence of the boronoethyl moiety.
• Biochemical Research: Used as a tool compound to study enzyme mechanisms, particularly those involving cysteine proteases, by acting as a reversible or irreversible inhibitor.
• Peptide Modification: Enables the site-specific incorporation of boron into peptides and proteins for structural and functional studies.
• Ligand Development: Utilized in creating novel chelating agents or ligands for various metals, leveraging the thiol and boronic acid functional groups.
• Material Science: Potential applications in creating functionalized surfaces or polymers with unique binding properties.

Basic Information

Product Name	S-(2-Boronoethyl)-L-Cysteine Hydrochloride
CAS No.	222638-67-7
Molecular Formula	C5H13BClNO4S
Molecular Weight	229.49 g/mol
Synonyms	L-Cysteine, S-(2-boronoethyl)-, hydrochloride; S-(2-Boronoethyl)cysteine hydrochloride; (2R)-2-Amino-3-[(2-boronoethyl)sulfanyl]propanoic acid hydrochloride; Bortezomib Intermediate; Bz-LLL-B(OH)2 precursor; Boronic acid cysteine derivative HCl
EINECS	Contact for details

Quality Control

Our S-(2-Boronoethyl)-L-Cysteine Hydrochloride is manufactured under controlled conditions to ensure high purity and batch-to-batch consistency, suitable for research and pharmaceutical development. Each lot undergoes rigorous analytical testing including HPLC for purity and chiral integrity, NMR for structural confirmation, and residual solvent analysis. A comprehensive Certificate of Analysis (COA) detailing all specifications is provided with every shipment.

Storage

Preserve in a tightly closed container, protected from light. Store in a cool, dry place at 2-8°C under an inert atmosphere (e.g., nitrogen or argon) due to its hygroscopic and easily oxidized nature. Allow the container to reach room temperature before opening to minimize moisture ingress.

Specification

Item	Specification
Appearance	White to off-white crystalline powder
Identification (IR)	Conforms to structure
Identification (NMR)	Conforms to structure
Purity (HPLC)	≥ 98.0%
Chiral Purity	≥ 99.0% (L-isomer)
Water Content (KF)	≤ 1.0%
Residual Solvents (GC)	Meets ICH guidelines
Heavy Metals	< 10 ppm

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