Description

n-Fmoc-4-Ethynyl-L-Phenylalanine CAS NO 1228049-41-9 is a high-purity, non-natural amino acid derivative featuring a protected amine (Fmoc) group and a reactive ethynyl side chain. This unique structure makes it an essential building block for the solid-phase synthesis of complex peptides and peptidomimetics, enabling the site-specific introduction of bioorthogonal handles for conjugation. It is primarily utilized by pharmaceutical researchers, peptide manufacturers, and bioconjugation specialists developing novel therapeutics, diagnostic probes, and advanced biomaterials.

Application

• Solid-Phase Peptide Synthesis (SPPS): A key protected amino acid for the Fmoc-strategy synthesis of peptides containing alkyne-functionalized phenylalanine residues.
• Bioconjugation & Click Chemistry: The terminal alkyne group enables efficient, site-specific conjugation via copper-catalyzed azide-alkyne cycloaddition (CuAAC) with azide-bearing molecules like dyes, polymers, or drug molecules.
• Peptidomimetic & Drug Discovery: Used to incorporate rigid, aromatic ethynyl groups into peptide backbones to modulate bioavailability, stability, and target binding affinity in novel drug candidates.
• Chemical Biology Probes: Serves as a precursor for synthesizing activity-based probes and photoaffinity labels to study protein function and interactions.
• Material Science: Employed in the synthesis of functionalized surfaces and smart polymers where precise peptide sequences are required.
• Antibody-Drug Conjugate (ADC) Development: Facilitates the construction of linker-payload systems with defined stoichiometry and attachment sites.

Basic Information

Product Name	n-Fmoc-4-Ethynyl-L-Phenylalanine
CAS No.	1228049-41-9
Molecular Formula	C₂₆H₂₁NO₄
Molecular Weight	411.45 g/mol
Synonyms	Fmoc-4-Ethynyl-L-Phe-OH; N-[(9H-Fluoren-9-ylmethoxy)carbonyl]-4-ethynyl-L-phenylalanine; (2S)-2-[(9H-Fluoren-9-ylmethoxy)formamido]-3-(4-ethynylphenyl)propanoic acid; Fmoc-Tyr(3-ethynyl)-OH; Fmoc-4-Ethynylphenylalanine; 4-Ethynyl-L-phenylalanine, N-Fmoc derivative; Fmoc-L-4-EthynylPhe-OH; Fmoc-Phe(4-ethynyl)-OH
EINECS	Contact for details

Quality Control

Our n-Fmoc-4-Ethynyl-L-Phenylalanine is manufactured under strict quality systems to ensure batch-to-batch consistency for critical research and development. Each lot undergoes rigorous analytical testing, including HPLC for purity and NMR for structural confirmation. Certificates of Analysis (COA) detailing purity, identity, and specific impurity profiles are provided with every shipment to support your regulatory and quality documentation needs.

Storage

Preserve in a tightly closed container, protected from light. Store at -20°C or below under an inert atmosphere for long-term stability. This compound is hygroscopic (moisture-sensitive). Allow the sealed container to equilibrate to room temperature before opening to prevent condensation and moisture uptake.

Specification

Item	Specification
Appearance	White to off-white powder
Identification (HPLC)	Conforms to reference standard
Identification (NMR)	Conforms to structure
Purity (HPLC)	≥ 98.0%
Specific Rotation	Contact for details
Water Content (KF)	≤ 0.5%
Heavy Metals	≤ 10 ppm

Note: Specifications can be tailored. Please contact us for the detailed technical data sheet of a specific grade.