Description

D-Cysteine CAS NO 921-01-7 is the D-enantiomer of the sulfur-containing amino acid cysteine, distinguished by its specific stereochemistry. This compound is a critical chiral building block and biochemical reagent, offering unique properties not found in its more common L-form counterpart. It serves as an essential raw material for researchers and manufacturers in the pharmaceutical, biotechnology, and specialty chemical synthesis sectors, where precise molecular configuration is paramount for activity and function.

Application

• Pharmaceutical Intermediates: A key chiral synthon in the research and production of specific peptide-based drugs and active pharmaceutical ingredients (APIs) where the D-configuration is required.
• Biochemical Research: Used as a substrate or inhibitor in enzymatic studies to investigate stereospecificity and metabolic pathways.
• Peptide Synthesis: An essential component for the solid-phase and solution-phase synthesis of non-natural peptides and peptidomimetics with tailored biological properties.
• Nutritional Science Studies: Employed in comparative metabolic research to understand the differential utilization of D- and L-amino acids.
• Cosmetic & Personal Care Ingredients: Potential use in the development of specialized hair-waving or depilatory formulations due to its ability to modify disulfide bonds.
• Reference Standard: Serves as a high-purity chromatographic standard for analytical method development and quality control in laboratories.

Basic Information

Product Name	D-Cysteine
CAS No.	921-01-7
Molecular Formula	C3H7NO2S
Molecular Weight	121.16 g/mol
Synonyms	(R)-2-Amino-3-mercaptopropanoic acid; D-2-Amino-3-mercaptopropionic acid; (R)-Cysteine; D-Cystein; D-Cys; (R)-2-Amino-3-sulfanylpropanoic acid; H-D-Cys-OH; D-(-)-Cysteine
EINECS	213-062-6

Quality Control

Our D-Cysteine is produced under strict quality management systems. Each batch is subjected to comprehensive analytical testing, including chiral purity assay, to ensure it meets stringent specifications for research and industrial use. A Certificate of Analysis (COA) detailing purity, optical rotation, and impurity profiles is provided with every shipment to guarantee traceability and consistency.

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) for long-term stability. This product is hygroscopic (moisture-sensitive) and easily oxidized; therefore, containers must be kept sealed and allowed to reach room temperature before opening to prevent moisture condensation.

Specification

Item	Specification
Appearance	White to off-white crystalline powder
Identification (IR)	Conforms
Assay (HPLC)	≥98.0%
Optical Rotation [α]20/D	-220° to -230° (c=1 in 1N HCl)
Chiral Purity (HPLC)	≥99.0% D-isomer
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.