Boc-Tyr-OH

Boc-Tyr-OH is a fundamental protected amino acid building block extensively utilized in peptide synthesis, where it serves as a key reagent for the introduction of L-tyrosine residues. The Boc group of Boc-Tyr-OH selectively masks the amino group of tyrosine, preventing unwanted reactions during the synthesis process while allowing for selective deprotection under acidic conditions. Boc-Tyr-OH is the standard building block for introducing tyrosine amino-acid residues by Boc solid-phase peptide synthesis (Boc SPPS). Beyond peptide synthesis, Boc-Tyr-OH is explored in cosmetic applications for its potential in formulating products that promote skin health, leveraging the antioxidant properties derived from the tyrosine moiety.

 

 Product Parameters

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Parameter	Specification
Product Name	Boc-Tyr-OH
CAS Number	3978-80-1
Molecular Formula	C₁₄H₁₉NO₅
Molecular Weight	281.31 g/mol
Appearance	White to off-white powder
Melting Point	133–135 °C (lit.); 133–141 °C
Optical Rotation	[α]²⁰/D +2.5 to +4.0° (c=2, acetic acid)
Boiling Point	423.97 °C (rough estimate)
Density	1.1755 (rough estimate)
Refractive Index	1.5230 (estimate)
pKa	2.98 ± 0.10 (predicted)
Solubility	DMSO (slightly), methanol (sparingly)
Storage Condition	Keep in dark place,Sealed in dry,Room Temperature

 

Product Advantages

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Standard Building Block for Boc SPPS

Boc-Tyr-OH is the standard building block for introducing tyrosine amino-acid residues by Boc solid-phase peptide synthesis (Boc SPPS). The Boc group provides robust protection of the α-amino functionality during chain assembly.

 

High Optical Purity for Chiral Integrity

Boc-Tyr-OH is supplied with high optical purity, confirmed by specific optical rotation ([α]²⁰/D +2.5 to +4.0° in acetic acid). This ensures the maintenance of chiral integrity during peptide synthesis — a critical parameter for biological activity.

 

Versatile Applications Across Research Fields

Boc-Tyr-OH is utilized not only in peptide synthesis but also explored in cosmetic applications for its potential in formulating products that promote skin health, leveraging the antioxidant properties derived from the tyrosine moiety. L-Tyrosine, the parent amino acid, is a precursor to catecholamines and exhibits in vitro antioxidant and antiradical activities.

 

Broad Utility in Therapeutic Peptide Development

Boc-Tyr-OH serves as a key building block in the synthesis of therapeutic proteins and vaccines. It has been successfully employed in the synthesis of complex peptides such as CCK-7 analogs.

 

Stable Crystalline Form for Convenient Handling

The crystalline solid form of Boc-Tyr-OH is stable under recommended storage conditions and convenient to weigh and handle. When stored at –20 °C in a sealed, dry container, the product maintains excellent stability.

 

Synthetic Route

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In a dry 50 mL round-bottom flask, dissolve (2S)-2-amino-3-(4-hydroxyphenyl)propionic acid (200 mg) in a mixture of dry 1,4-dioxane (10 mL) and H₂O (5 mL; ratio 2:1). Add NaOH (1 M, 5 mL, 5 mmol, 4.5 equivalents) and Boc₂O (0.28 mL, 1.21 mmol) sequentially to the solution. Stir the reaction mixture at room temperature for 3 hours while monitoring the reaction progress via LC-MS. Upon completion, acidify the solution with 2 M HCl to pH approximately 2–3. Extract the resulting mixture three times with ethyl acetate (3 × 25 mL), combine all organic layers, wash them with saline, separate the organic layer, dry it with anhydrous Na₂SO₄, filter to remove the desiccant, and concentrate the filtrate under vacuum to eliminate the organic solvent. The crude product is then purified by silica gel column chromatography to yield the target compound N-tert-butoxycarbonyl-L-tyrosine.

 

Application

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Boc-Tyr-OH is a derivative of L-tyrosine in which the nitrogen atom is protected by a Boc group, and is commonly used as an intermediate in biochemical synthesis as well as a raw material for the synthesis of peptide-based pharmaceutical molecules.

 

Contact Us

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Looking for Boc-Tyr-OH to power your Boc SPPS campaign or peptide therapeutic development? Cosperpharm is your trusted partner for high-quality protected amino acids. Contact us today for pricing, documentation, or technical support — we‘re ready to assist.