Description

H-D-Cys(Fm)-Oh CAS NO 257288-48-5 is a protected cysteine derivative, specifically the Fmoc-protected form of D-cysteine. This chiral amino acid building block is essential for the controlled synthesis of peptides and peptidomimetics, ensuring correct stereochemistry and preventing unwanted side reactions during coupling steps. It is a critical raw material for research institutions and manufacturers in the pharmaceutical and biotechnology sectors developing therapeutic peptides, diagnostic agents, and complex organic molecules.

Application

• Solid-Phase Peptide Synthesis (SPPS): A fundamental building block for the incorporation of D-cysteine residues using Fmoc-chemistry protocols.
• Pharmaceutical Intermediates: Serves as a key chiral synthon in the production of active pharmaceutical ingredients (APIs) for various therapeutic areas.
• Bioconjugation and Linker Chemistry: Utilized to introduce thiol-reactive sites or disulfide bridges into biomolecules for drug delivery systems and antibody-drug conjugates (ADCs).
• Research & Development: Used in academic and industrial R&D for exploring novel peptide structures, studying enzyme inhibitors, and developing biochemical probes.
• Asymmetric Synthesis: Acts as a chiral auxiliary or starting material in the synthesis of non-peptidic compounds requiring high enantiomeric purity.

Basic Information

Product Name	H-D-Cys(Fm)-Oh
CAS No.	257288-48-5
Molecular Formula	C₁₈H₁₇NO₄S
Molecular Weight	343.40 g/mol
Synonyms	Fmoc-D-cysteine; (R)-2-(((9H-Fluoren-9-yl)methoxy)carbonyl)amino)-3-mercaptopropanoic acid; D-Cysteine, N-[(9H-fluoren-9-ylmethoxy)carbonyl]-; N-Fmoc-D-cysteine; N-[(9-Fluorenylmethoxy)carbonyl]-D-cysteine; Fmoc-D-Cys-OH; (R)-2-((((9H-Fluoren-9-yl)methoxy)carbonyl)amino)-3-sulfanylpropanoic acid
EINECS	Contact for details

Quality Control

Every batch of H-D-Cys(Fm)-Oh is manufactured and tested under strict quality management systems. We provide comprehensive analytical data to ensure the product meets the high-purity standards required for sensitive synthetic applications. A Certificate of Analysis (COA) detailing purity, chiral purity, and impurity profiles by HPLC is supplied with each shipment.

Storage

Preserve in a tightly closed container, protected from light. Store in a cool, dry place at 2-8°C. This product is hygroscopic (moisture-sensitive) and should be handled under anhydrous conditions to maintain stability and purity. For long-term storage, consider storage under an inert atmosphere.

Specification

Item	Specification
Appearance	White to off-white crystalline powder
Identification (HPLC/MS)	Conforms
Purity (HPLC)	≥98.0%
Chiral Purity (HPLC)	≥99.0%
Water Content (KF)	≤0.5%
Heavy Metals	≤10 ppm

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