Description

L-Cysteine Ethyl Ester Hydrochloride is a protected derivative of the essential amino acid L-Cysteine, widely used as a key chiral building block and biochemical reagent. This compound is valued for its enhanced stability and solubility in organic solvents compared to the free amino acid, facilitating its use in complex synthetic pathways. It is a critical intermediate for researchers and manufacturers in the pharmaceutical, nutraceutical, and peptide synthesis industries.

Application

• Pharmaceutical Intermediate: A crucial chiral synthon in the synthesis of active pharmaceutical ingredients (APIs), particularly for drugs targeting the central nervous system and metabolic disorders.
• Peptide Synthesis: Serves as a protected cysteine residue in solid-phase and solution-phase peptide synthesis, preventing unwanted disulfide bond formation during assembly.
• Biochemical Research: Used as a substrate or precursor in enzymatic studies and for investigating biochemical pathways involving thiol groups.
• Nutraceutical & Cosmetic Applications: Employed in the development of advanced supplements and skincare products where stabilized cysteine derivatives are required.
• Flavor & Fragrance Industry: Acts as a precursor in the Maillard reaction for creating savory meat-like flavors and aroma compounds.

Basic Information

Product Name	L-Cysteine Ethyl Ester Hydrochloride
CAS No.	868-59-7
Molecular Formula	C5H12ClNO2S
Molecular Weight	185.67 g/mol
Synonyms	L-Cysteine ethyl ester HCl; (R)-2-Amino-3-mercaptopropanoic acid ethyl ester hydrochloride; Ethyl L-cysteinate hydrochloride; Cysteine ethyl ester monohydrochloride; H-Cys-OEt·HCl; L-Cysteine ethylester hydrochloride; NSC 3349
EINECS	212-763-3

Quality Control

Our L-Cysteine Ethyl Ester Hydrochloride is manufactured under strict quality management systems. Each batch undergoes comprehensive analytical testing to ensure it meets high-purity standards suitable for pharmaceutical and research applications. A Certificate of Analysis (COA) detailing specific results for identity, purity, and related substances is provided with every shipment.

Storage

Preserve in a tightly closed container, protected from light. Store in a cool, dry, and well-ventilated place at 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%
Specific Rotation [α]20/D	+7.0° to +9.0° (c=1 in H2O)
Loss on Drying	≤0.5%
Residue on Ignition	≤0.1%
Heavy Metals (as Pb)	≤10 ppm

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