Description

Fmoc-Cys(Tbu)-Opfp is a specialized, high-purity amino acid derivative used in solid-phase peptide synthesis (SPPS). This compound matters because it provides a protected cysteine residue, essential for the controlled formation of disulfide bonds in complex peptide and protein sequences. Pharmaceutical researchers, biotechnology companies, and CROs need it for the development of therapeutic peptides, APIs, and biochemical research tools. Its design ensures efficient coupling and orthogonal deprotection strategies critical for modern synthetic workflows.

Application

• Solid-Phase Peptide Synthesis (SPPS): A key building block for the controlled incorporation of cysteine into peptide chains.
• Therapeutic Peptide Development: Used in the research and production of peptide-based pharmaceuticals, including hormones, antimicrobial peptides, and targeted therapeutics.
• Disulfide Bridge Formation: Essential for the synthesis of peptides requiring specific, stable tertiary structures through intramolecular disulfide bonds.
• Bioconjugation and Labeling: Serves as a handle for site-specific modification of peptides and proteins with fluorophores, PEG chains, or other functional groups.
• Chemical Biology Research: Employed in the study of protein-protein interactions, enzyme mechanisms, and the development of peptide probes.
• API Intermediate Manufacturing: Acts as a critical raw material in the multi-step synthesis of active pharmaceutical ingredients (APIs) for GMP production.

Basic Information

Product Name	Fmoc-Cys(Tbu)-Opfp
CAS No.	109434-23-3
Molecular Formula	C₂₄H₂₄F₅NO₅S
Molecular Weight	533.51 g/mol
Synonyms	Fmoc-Cys(Trt)-Opfp; Fmoc-S-tert-butyl-L-cysteine pentafluorophenyl ester; N-[(9H-Fluoren-9-ylmethoxy)carbonyl]-S-(tert-butyl)-L-cysteine 2,3,4,5,6-pentafluorophenyl ester; Fmoc-Cys(tBu)-OPfp; Fmoc-Cysteine(Trt)-OPfp ester; Nα-Fmoc-S-tert-butyl-L-cysteine pentafluorophenyl ester; Fmoc-S-tert-butylcysteine pentafluorophenyl ester; Fmoc-L-Cys(Trt)-OPfp
EINECS	Contact for details

Quality Control

Our Fmoc-Cys(Tbu)-Opfp is manufactured under strict quality systems to ensure batch-to-batch consistency and high purity for demanding synthetic applications. Each lot undergoes rigorous analytical testing, including HPLC for purity and identity confirmation by NMR and mass spectrometry. Certificates of Analysis (COA) with detailed specifications are provided and can be tailored to meet specific project or regulatory requirements, supporting development from research to GMP-grade production.

Storage

Preserve in a tightly closed container, protected from light. Store at -20°C or below in a freezer. This product is hygroscopic (moisture-sensitive) and should be handled under anhydrous conditions. Allow the sealed container to equilibrate to room temperature before opening to prevent condensation.

Specification

Item	Specification
Appearance	White to off-white crystalline powder
Identification (HPLC)	Conforms to reference standard
Identification (NMR)	Conforms to structure
Purity (HPLC)	≥ 98.0%
Specific Rotation	Contact for details
Water Content (KF)	≤ 0.5%
Heavy Metals	≤ 20 ppm
Residual Solvents	Complies with ICH guidelines

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