Description

Cysteine(4-Methoxytrityl)-Oh is a protected derivative of the amino acid cysteine, featuring a 4-methoxytrityl (MMT) group on the thiol side chain. This compound is critically important as a key building block in solid-phase peptide synthesis (SPPS), where it provides selective protection for the cysteine thiol group, preventing unwanted side reactions during chain assembly. It is an essential raw material for research institutions and manufacturers developing therapeutic peptides, diagnostic agents, and biochemical tools where the precise incorporation of cysteine is required.

Application

• Solid-Phase Peptide Synthesis (SPPS): As a protected amino acid derivative for the controlled introduction of cysteine residues into peptide sequences.
• Pharmaceutical Intermediates: Serves as a critical precursor in the synthesis of peptide-based active pharmaceutical ingredients (APIs) and drug candidates.
• Bioconjugation Chemistry: Used in the preparation of peptide-protein conjugates, antibody-drug conjugates (ADCs), and other bioconjugates where a free thiol is needed post-deprotection.
• Research & Development: A vital reagent in academic and industrial R&D labs for studying protein structure, function, and for developing novel biomolecules.
• Combinatorial Chemistry: Employed in the generation of peptide libraries for high-throughput screening in drug discovery.

Basic Information

Product Name	Cysteine(4-Methoxytrityl)-Oh
CAS No.	177582-20-6
Molecular Formula	C23H23NO4S
Molecular Weight	409.50 g/mol
Synonyms	S-(4-Methoxytrityl)-L-cysteine; L-Cysteine, S-[(4-methoxyphenyl)diphenylmethyl]-; Fmoc-Cys(Mmt)-OH (Note: This often refers to the N-Fmoc protected version); Cys(Mmt)-OH; S-MMT-L-cysteine; 4-Methoxytrityl-L-cysteine; (2R)-2-amino-3-[[(4-methoxyphenyl)-diphenylmethyl]sulfanyl]propanoic acid
EINECS	Contact for details

Quality Control

Our Cysteine(4-Methoxytrityl)-Oh is manufactured under strict quality management systems. Each batch undergoes rigorous analytical testing, including HPLC for purity and chiral purity assessment, to ensure it meets the high standards required for peptide synthesis. Certificates of Analysis (COA) with detailed chromatographic data are provided for every shipment, ensuring traceability and consistency for your critical applications.

Storage

Preserve in a tightly closed container, protected from light. Store in a cool, dry place at 15-25°C. This material is hygroscopic (moisture-sensitive) and should be handled under dry conditions to maintain stability and performance.

Specification

Item	Specification
Appearance	White to off-white powder
Identification (IR)	Conforms to structure
Assay (HPLC)	≥98.0%
Chiral Purity (HPLC)	≥99.0% L-isomer
Water Content (KF)	≤1.0%
Heavy Metals	≤20 ppm

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