Fmoc-L-Tyr(PO3H2)-OH

Fmoc-L-Tyr(PO3H2)-OH is an Fmoc-protected L-tyrosine derivative bearing a phosphonic acid group on the phenolic side chain, yielding a chiral amino acid building block with a strongly polar, anionic-capable functionality. The molecule combines an aromatic phenyl ring, a phenolic substituent converted to a phosphonic acid (PO3H2), and a free carboxylic acid suitable for peptide coupling chemistry after activation. The Fmoc group on the α-amino function provides orthogonal protection that can be removed under standard base conditions to expose the amine for sequential chain assembly. The phosphonic acid moiety can participate in acid-base equilibria and can coordinate metal ions, which influences solubility, coupling behavior, and downstream derivatization of the side-chain phosphate chemistry.

1. Peptide Synthesis

Fmoc-L-Tyr(PO3H2)-OH supports solid-phase peptide synthesis where tyrosine analogs with side-chain phosphonic acid mimic phosphorylated residues while retaining the aromatic scaffold for recognition studies. The Fmoc-protected α-amino group enables controlled N-terminal deprotection and peptide coupling, while the carboxylic acid allows incorporation as a residue at a growing peptide terminus. The PO3H2 side chain can be used to generate peptide analogs that maintain a persistent negative charge character relative to labile phosphate esters, supporting stable phosphomimetic designs. The resulting phosphonic-acid-containing peptides can be applied to mapping phosphorylation-dependent binding motifs and to construct peptide building blocks for biochemical assays and materials-oriented peptide frameworks.

2. Chemical Biology

Fmoc-L-Tyr(PO3H2)-OH is applicable in chemical biology workflows that require phosphotyrosine-like functionality for probing kinase recognition, SH2/SH3 domain interactions, or phospho-dependent molecular recognition. The phosphonic acid group provides a strong hydrogen-bonding and metal-coordinating motif and can be incorporated as a stable surrogate for phosphorylated tyrosine in mechanistic studies. The aromatic ring and stereodefined L-configuration maintain the geometric context typical of tyrosine residues, while the protected amine and terminal carboxyl group support incorporation into peptides used as probes. Downstream peptide conjugates and phosphomimetic constructs derived from this amino acid can serve as research intermediates for receptor-binding studies, signal transduction mimicry, and structure-function investigations of phosphorylation pathways.

3. Peptidomimetics And SAR Studies

Fmoc-L-Tyr(PO3H2)-OH can be employed in peptidomimetic and structure-activity relationship studies where phosphonic-acid-substituted tyrosine residues tune electrostatics and binding geometry. The PO3H2 side chain functions as a persistent anionic group that can be retained through synthetic sequences, enabling systematic variation of side-chain charge density in peptide analog libraries. The Fmoc strategy supports parallel synthesis of multiple analogs by sequential deprotection/coupling, while the aromatic core provides a hydrophobic and π-interaction handle for receptor engagement. The resulting phosphomimetic scaffolds can be used to generate SAR-focused series for fragment-to-lead optimization and for comparing binding modes across closely related amino acid derivatives.

4. Bioconjugation Chemistry

Fmoc-L-Tyr(PO3H2)-OH can be utilized as a defined phosphonic-acid-containing amino acid intermediate for bioconjugation schemes that require stable phosphate-like linkers. The phosphonic acid moiety can undergo controlled functional group transformations to introduce reactive handles for attaching peptides to biomolecules or surfaces, while the aromatic tyrosine framework can support affinity-based capture strategies in conjugate workflows. The Fmoc-protected amine and terminal carboxylic acid enable conversion into peptide conjugation reagents through peptide coupling compatibility, supporting the construction of multivalent biomolecule conjugates. Downstream products derived from this building block can be applied in labeling, affinity probe preparation, and analytical reagent synthesis where charge-stable phosphonic motifs improve conjugate robustness.

5. Pharmaceutical Manufacturing Intermediates

Fmoc-L-Tyr(PO3H2)-OH is suitable for process chemistry and pharmaceutical intermediate preparation when phosphomimetic tyrosine residues are required in peptide-active or peptide-adjacent manufacturing routes. The orthogonal Fmoc protection on the α-amino group supports reproducible N-protection/N-deprotection logic in automated synthesis settings, while the carboxylic acid enables standard activation chemistry for residue coupling. The phosphonic acid side chain provides a chemically stable alternative to transient phosphate esters, which can reduce sensitivity to hydrolysis during downstream processing and formulation development. The compound can therefore serve as a controlled chiral input for producing phosphonic-acid-containing peptide intermediates that feed into larger-scale synthesis of functional peptide materials and research-grade manufacturing batches.

6. Analytical Research Standards

Fmoc-L-Tyr(PO3H2)-OH can be applied in analytical research as a reference amino acid and derivatization precursor for monitoring phosphomimetic peptide synthesis and characterizing side-chain integrity. The defined PO3H2 group provides a characteristic, highly polar signature that can assist in method development for LC-MS, ion-exchange behavior, and phosphonic-acid-specific detection strategies. The Fmoc-protected structure and the L-tyrosine stereochemical definition enable consistent incorporation into peptides used as internal standards or calibration surrogates. The resulting analytical standards and labeled or derivatized derivatives can support routine quality assessment of peptide building block preparation, peptide coupling outcomes, and phosphonic side-chain stability during synthetic and purification workflows.

1. Immune-awakening Saccharomyces-inspired nanocarrier for oral target delivery to lymph and tumors

2. Zeta-potential-changing nanoparticles conjugated with cell-penetrating peptides for enhanced transfection efficiency

3. An Open-label, Single-center, Safety and Efficacy Study of Eyelash Polygrowth Factor Serum

4. Therapeutic potential of an intestinotrophic hormone, glucagon-like peptide 2, for treatment of type 2 short bowel syndrome rats with intestinal bacterial and fungal dysbiosis

5. An Isolated TCR αβ Restricted by HLA-A* 02: 01/CT37 Peptide Redirecting CD8+ T Cells to Kill and Secrete IFN-γ in Response to Lung Adenocarcinoma Cell Lines