Fmoc-Thr(tBu)-OH

Fmoc-Thr(tBu)-OH serves as the standard building block for introducing L-threonine residues into peptides via Fmoc-based solid-phase peptide synthesis (SPPS). The tert-butyl side-chain protecting group on Fmoc-Thr(tBu)-OH is stable under the basic conditions of Fmoc deprotection (typically 20% piperidine in DMF) but is readily removed by TFA during final cleavage from the resin, allowing controlled, stepwise assembly of peptide chains without side reactions at the hydroxyl group. Fmoc-Thr(tBu)-OH has been used to synthesize chlorofusin analogues via solid-phase peptide synthesis and to serve as a protecting group for both amine and hydroxyl functions in the solid-phase synthesis of complex depsipeptides.

Product Parameters

Synthetic Route

Fmoc-Thr(tBu)-OH is prepared by Fmoc protection of O-tert-butyl-L-threonine. The synthesis involves reacting O-tert-butyl-L-threonine with 9-fluorenylmethoxycarbonyl chloride (Fmoc-Cl) in the presence of a base such as sodium carbonate in an aqueous-organic biphasic system (typically water/1,4-dioxane). After completion of the reaction, the product is extracted, washed, and the crude Fmoc-protected amino acid is isolated by precipitation or crystallization. Industrial production scales follow the same synthetic route, with reactions optimized for higher yields and purity, often involving advanced purification techniques such as recrystallization or preparative HPLC to achieve ≥98% purity.

Storage Conditions

Store Fmoc-Thr(tBu)-OH in a tightly sealed container at 2–8 °C for short-term storage or at -20 °C for long-term storage. Keep the container dry, protected from light, and stored away from strong oxidizing agents and strong bases. For maximum recovery of product, centrifuge the original vial prior to removing the cap. Once dissolved in solvent (e.g., DMSO), the solution should be stored in separate aliquots to avoid product degradation caused by repeated freezing and thawing. When stored at -80 °C, the solution can be used within 6 months; when stored at -20 °C, within 1 month.

Shelf life: 3 years when stored as powder at -20 °C; 2 years at 4 °C.

Handling precautions: Use in a fume hood. Wear chemical‑resistant gloves, safety goggles, and a lab coat. Avoid generating dust. Wash hands thoroughly after handling. Refer to the Safety Data Sheet (SDS) for complete safety information.

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When your peptide synthesis requires consistent quality and reliable supply, choose Cosperpharm. Contact us today to discuss your Fmoc-Thr(tBu)-OH requirements — whether you need a few grams for method development or kilograms for commercial manufacturing.