Description

S-(4-Nitrophenyl)-L-Cysteine is a specialized, high-purity biochemical building block featuring a chiral L-cysteine backbone modified with a 4-nitrophenyl thioether group. This compound matters as a critical intermediate and research tool in advanced organic synthesis and pharmaceutical development, where its unique structure enables the study of enzyme mechanisms and the construction of complex molecules. It is primarily needed by research institutions, pharmaceutical R&D departments, and fine chemical manufacturers focused on developing novel therapeutics, enzyme inhibitors, and biochemical probes.

Application

• Pharmaceutical Intermediate: Key building block in the synthesis of novel drug candidates, particularly those targeting enzyme active sites containing cysteine residues.
• Biochemical Research: Used as a substrate or inhibitor in enzymatic studies to investigate reaction mechanisms, particularly for cysteine proteases and transferases.
• Peptide Synthesis: Serves as a modified cysteine derivative for the solid-phase or solution-phase synthesis of peptides with specific redox or binding properties.
• Proteomics & Labeling Reagent: Potential use in affinity labeling or as a tag in chemical proteomics to study protein function and interactions.
• Reference Standard: Employed as an analytical standard in quality control laboratories for method development and validation in pharmaceutical analysis.

Basic Information

Product Name	S-(4-Nitrophenyl)-L-Cysteine
CAS No.	55288-30-7
Molecular Formula	C9H10N2O4S
Molecular Weight	242.25 g/mol
Synonyms	L-Cysteine, S-(4-nitrophenyl)-; (R)-2-Amino-3-((4-nitrophenyl)thio)propanoic acid; 4-Nitrothiophenol-L-cysteine adduct; S-(p-Nitrophenyl)-L-cysteine; p-Nitrophenyl L-cysteine thioether; NSC 113928; 4-Nitrobenzenethiol, cysteine adduct
EINECS	Contact for details

Quality Control

Our S-(4-Nitrophenyl)-L-Cysteine is manufactured under strict quality management systems. Each batch undergoes rigorous analytical testing, including HPLC for purity, chiral analysis to confirm the L-configuration, and identity confirmation by IR and NMR spectroscopy. A comprehensive Certificate of Analysis (COA) detailing all test results is provided with every shipment to ensure traceability and compliance with your research or production specifications.

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) to minimize oxidation. Keep the container sealed to protect this moisture-sensitive material from humidity. For long-term storage, consider freezing at -20°C.

Specification

Item	Specification
Appearance	White to light yellow crystalline powder
Identification (IR)	Conforms to structure
Identification (NMR)	Conforms to structure
Purity (HPLC)	≥ 98.0%
Chiral Purity (HPLC)	≥ 99.0% L-isomer
Water Content (KF)	≤ 1.0%
Residue on Ignition	≤ 0.1%

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