Sigma-Aldrich™ Novabiochem® Fmoc-Cys(Trt)-OH, ≥99.0% (HPLC)

Fmoc-Cys(Trt)-OH (Fmoc-protected cysteine trityl ester) is a high-purity amino acid derivative designed for solid-phase peptide synthesis (SPPS). This compound provides:

• Fmoc (9-fluorenylmethyloxycarbonyl) protection on the N-terminal amine, allowing controlled deprotection during peptide elongation.
• Trt (Trityl) protection on the cysteine thiol (-SH) group, preventing oxidation and side reactions until selective removal is required.

This reagent is essential for cysteine-containing peptide synthesis, particularly in cyclic peptide formation, native chemical ligation (NCL), and protein engineering. It offers excellent solubility in DMF, minimal impurities, and high enantiomeric purity (≥99.5%), making it a gold-standard reagent in peptide chemistry.

Key Features & Benefits

✔ High Purity (≥99.0%) – Ensures consistent, high-quality peptide synthesis.

✔ Fmoc & Trt Protection – Provides selective deprotection, ensuring precise peptide assembly.

✔ Ideal for Solid-Phase Peptide Synthesis (SPPS) – Minimizes oxidation and side reactions during peptide elongation.

✔ Stable & Well-Characterized – HPLC assay (≥99.0%), low impurity levels, and strict quality control guarantee high performance.

✔ Proven Compatibility with Multiple Activation Methods – Compatible with DIPCDI/HOBt, symmetrical anhydride, or uronium/phosphonium reagents (HBTU, PyBOP®) with collidine as a base to prevent enantiomerization.

Chemical Properties & Identifiers

Applications

🔹 Peptide Synthesis & Proteomics Research – Used in Fmoc-based SPPS for cysteine incorporation.

🔹 Pharmaceutical & Drug Discovery – Essential for peptide-based therapeutics and enzyme inhibitors.

🔹 Cyclic Peptide & Protein Engineering – Facilitates disulfide bond formation and controlled thiol chemistry.

🔹 Native Chemical Ligation (NCL) – Used in C-terminal peptide modifications and semi-synthetic protein synthesis.

✔ Reported Applications Include:

1️⃣ Synthesis of Cyclic Peptides via Tandem N-to-S Acyl Migration and Thiol-Additive-Free Ligation – Enhancing resin-based peptide cyclization. (Serra et al., 2020)

2️⃣ Selective Bi-Directional Amide Bond Cleavage of N-Methylcysteinyl Peptides – Used for controlled peptide modifications. (Qiu et al., 2014)

Storage & Handling

📦 Storage Conditions:

• Store at -20°C (between −15°C to −25°C) in a dry, tightly sealed container.
• Protect from moisture, oxidation, and light exposure.

⚠ Handling Precautions:

• Use in a well-ventilated environment.
• Wear PPE – gloves, lab coat, and safety goggles.
• Avoid exposure to acidic or basic conditions before controlled deprotection.

General References & Research Citations

1️⃣ S. N. McCurdy (1989) – Standard derivative for Fmoc-SPPS of cysteine-containing peptides. Pept. Res., 2, 147.

2️⃣ T. Kaiser et al. (1996) – Fmoc-Cys(Trt)-OH for cysteine-containing peptides. Tetrahedron Lett., 37, 1187.

3️⃣ Y. X. Han et al. (1997) – Use of Fmoc-Cys(Trt)-OH in synthetic peptides. J. Org. Chem., 62, 4307.

4️⃣ Y. N. Angell (2002) – Effects of coupling reagents on enantiomeric stability. J. Peptide Res., 5, 292.

Regulatory & Safety Information

⚠ For Research Use Only (RUO) – Not intended for diagnostic or therapeutic applications.

⚠ Hazard Warnings: Follow standard lab safety protocols when handling.

Ordering Information

📦 Shipping Conditions: Dry ice for temperature control.

Sigma-Aldrich™ Novabiochem® Fmoc-Cys(Trt)-OH (≥99.0%) is a high-purity, selectively protected cysteine derivative essential for solid-phase peptide synthesis (SPPS), cyclic peptide formation, and protein engineering. Its Fmoc and Trt protection allow precise control over cysteine incorporation, making it ideal for bioconjugation, native chemical ligation (NCL), and biomedical applications.