Fmoc-Asn(Trt)-OH

Fmoc-Asn(Trt)-OH is a high‑purity Fmoc‑protected amino acid specifically designed for the incorporation of L‑asparagine into synthetic peptides via Fmoc SPPS, with the side‑chain amide protected by a trityl (Trt) group to prevent undesirable side reactions. In standard SPPS workflows, Fmoc-Asn(Trt)-OH is coupled to resin‑bound peptide chains using standard coupling reagents such as HBTU/HOBt, HATU, or PyBOP in the presence of DIPEA. The Fmoc group is removed with piperidine to expose the α-amine for the next coupling cycle, while the trityl‑protected side chain remains fully intact throughout chain assembly. At the conclusion of peptide synthesis, the trityl group is removed under mild acidic conditions — typically with 1–5% TFA in DCM over 1-3 hours — revealing the native asparagine side chain without alkylation of sensitive residues such as tryptophan. Fmoc-Asn(Trt)-OH has been shown to result in significantly purer crude peptides than other asparagine derivatives, with documented low levels of dipeptide, free ‑amino acid, and acetic acid impurities. Fmoc-Asn(Trt)-OH has good solubility properties in most organic solvents, and has been used to synthesize peptides on cellulose membranes by the SPOT method. Fmoc-Asn(Trt)-OH is compatible with standard Fmoc SPPS protocols and is suitable for both research‑scale synthesis and GMP‑grade peptide manufacturing, with purity levels ranging from ≥97% to ≥99% available from Cosperpharm.

Product Parameters

Why Cosperpharm？

Quality that protects your peptide purity. Every shipment of Fmoc-Asn(Trt)-OH from Cosperpharm is released only after passing our comprehensive analytical release protocol: HPLC purity verification (≥97%, ≥98%, or ≥99% depending on grade), enantiomeric purity verification by chiral HPLC (≥99.7%), water content determination by Karl Fischer (≤1%–2%), residual solvent analysis (ethyl acetate ≤0.5%, acetate ≤0.05%), identity confirmation by ¹H NMR and IR, specific optical rotation measurement ([α]²⁰/D −15±1°, c=1% in methanol), and targeted impurity testing for dipeptide byproducts, Fmoc‑Asn‑OH, and Fmoc‑β‑Ala‑containing impurities. The low impurity profile of Fmoc-Asn(Trt)-OH from Cosperpharm — with each specific impurity controlled to ≤0.1% — ensures that your final crude peptides are significantly purer and require less downstream purification.

Documentation that supports regulatory submissions. For customers working on GMP peptide manufacturing or ANDA filings for peptide drug substances, Cosperpharm provides DMF‑ready documentation packages, method validation reports, and comprehensive stability data upon request. Every shipment includes a detailed Certificate of Analysis (COA) with batch‑specific purity data, impurity profiles, water content, residual solvent analysis, and identity confirmation — structured for direct insertion into your documentation systems and regulatory dossiers.

Flexible supply across all development scales. Cosperpharm supplies Fmoc-Asn(Trt)-OH across the full range of applications — from 1g–100g quantities for research and method development, to 500g–5kg batches for process validation and pilot production, to bulk quantities (up to 25kg or more) for commercial GMP peptide manufacturing. R&D samples typically ship within 5–7 business days; bulk orders ship within 2–3 weeks.

Technical support from experienced peptide chemists. Our process chemistry team has extensive hands‑on experience in Fmoc SPPS and can advise on coupling optimization for asparagine residues, selection of appropriate side‑chain protection strategies, and impurity profiling — because we have worked extensively with Fmoc-Asn(Trt)-OH across numerous peptide manufacturing campaigns.

Global logistics with transparent pricing. Cosperpharm ships to pharmaceutical manufacturers, CDMOs, CROs, and research institutions worldwide, with full customs documentation included. Volume discounts apply at kilogram scales, and we communicate lead times clearly upfront — no hidden fees, no unexpected delays.

Synthetic Routine

Storage Conditions

Store Fmoc-Asn(Trt)-OH in a tightly sealed, desiccated container under inert atmosphere (nitrogen or argon) at −20 °C for long‑term storage or at 2–8 °C (refrigerated) for short‑term storage (up to 6 months). Keep the container dry, protected from light, and stored in a clean, well‑ventilated area away from strong oxidizing agents and sources of moisture. The compound is stable under recommended storage conditions. Due to its sensitivity to moisture, desiccated storage is essential, and the container should be opened only in a low‑humidity environment. Allow the sealed container to reach ambient temperature before opening to minimize moisture condensation.

Shelf life: 2–3 years when stored at −20 °C in a sealed, desiccated container under inert atmosphere; 6–12 months when stored at 2–8 °C.

GHS information: Fmoc-Asn(Trt)-OH is classified as Aquatic Chronic 2. Storage Class: 11 — Combustible Solids. Signal Word: Warning. PPE recommended: Eyeshields, Gloves, type N95 (US) or equivalent respirator protection.

Handling precautions: Use only in a fume hood. Wear chemical‑resistant gloves (tested against EN 374 or equivalent), safety goggles, and a lab coat. Avoid generating dust or aerosols. Do not eat, drink, or smoke in work areas. After handling, wash hands thoroughly. Contaminated clothing should be removed and washed before reuse. Refer to the Safety Data Sheet (SDS) for complete safety information.

Special note: The trityl group in Fmoc-Asn(Trt)-OH is acid‑labile. Store away from strong acids. When Asn(Trt) is the N‑terminal residue, ensure adequate deprotection time at the end of synthesis to achieve complete Trt removal.

Contact Us

Ready to secure Fmoc-Asn(Trt)-OH for your peptide synthesis campaign? Whether you need research quantities for method development, pilot batches for process validation, or bulk shipments for GMP peptide manufacturing, Cosperpharm delivers the quality and reliability your project demands. Our team is ready to answer your technical questions, provide documentation support, and deliver the building blocks you need — on time and on spec. Contact us today to discuss your requirements.