Fmoc-alpha-Me-L-Phe(2,6-F2)-OH

Fmoc-alpha-Me-L-Phe(2,6-F2)-OH is an Fmoc-protected, chiral amino acid derivative built on an L-phenylalanine scaffold bearing a side-chain 2,6-difluoro substitution and an alpha-methyl stereocenter (α-Me). The molecule contains the fluorenylmethoxycarbonyl (Fmoc) carbamate on the amino group, a free carboxylic acid for peptide coupling, and a hydrophobic aromatic ring that is electronically modulated by the two fluorine atoms at the 2,6-positions. The α-methyl substitution increases steric bulk around the backbone, influencing coupling kinetics and the conformational bias of resulting peptide segments, while the difluoro pattern can affect hydrogen bonding, dipole distribution, and metabolic stability in downstream analogs. The combination of a protected amine and a reactive acid functionality makes the compound compatible with standard protected amino acid chemistry and peptide building-block workflows.

1. Peptide Synthesis

Fmoc-alpha-Me-L-Phe(2,6-F2)-OH serves as a protected amino acid building block for solid-phase peptide synthesis where the Fmoc group enables iterative N-protection and base-mediated deprotection cycles. The free carboxylic acid supports amide bond formation to incoming amino acid residues, while the L-configuration and α-methyl stereocenter maintain stereochemical fidelity at the peptide backbone. The 2,6-difluorophenyl side chain provides a defined aromatic motif that can be incorporated into peptides to tune hydrophobic contacts and aromatic electronics during sequence assembly. The resulting peptide analogs can be generated for structure-activity relationship studies and for mapping how backbone methylation and difluoro substitution alter folding propensity and binding interfaces in biochemical assays.

2. Peptidomimetics And SAR Studies

Fmoc-alpha-Me-L-Phe(2,6-F2)-OH is suitable for peptidomimetic construction and medicinal chemistry-oriented SAR studies due to its stereodefined α-methylated backbone and difluorinated aromatic side chain. The α-methyl group can bias local conformations and modulate protease recognition, while the 2,6-difluoro substitution changes aromatic ring polarity and can influence noncovalent interactions such as electrostatic complementarity and van der Waals packing. The Fmoc-protected amine and carboxylic acid functionality allow incorporation into peptide-like scaffolds and systematic library synthesis using protected amino acid coupling strategies. Downstream derivatives prepared from this building block can include constrained analogs, sequence variants, and fragment-defined constructs used to correlate structural modifications with binding or functional readouts in chemical biology workflows.

3. Chemical Biology Probes

Fmoc-alpha-Me-L-Phe(2,6-F2)-OH can be employed in chemical biology for generating labeled or functionalized peptide probes where fluorinated aromatic residues provide a handle for physicochemical tracking and interaction mapping. The difluorophenyl side chain can participate in specific hydrophobic and dipolar interactions, supporting design of probes that interrogate binding pockets or receptor-like recognition sites with controlled aromatic electronics. The protected amino acid format enables stepwise assembly of probe peptides with defined stereochemistry, including retention of the L-configuration and α-methyl stereocenter. The resulting fluorinated peptide constructs can be used as research intermediates for affinity studies, competition experiments, and mechanistic investigations that rely on precise side-chain identity and peptide backbone modification.

4. Side-Chain Functionalization

Fmoc-alpha-Me-L-Phe(2,6-F2)-OH supports downstream synthetic routes that leverage the difluorinated aromatic ring as a modifiable platform in amino acid derivatization chemistry. The 2,6-difluoro substitution pattern can enable selective functional transformations on the aryl ring under appropriate conditions, allowing access to substituted aromatic analogs while maintaining the α-methylated backbone stereochemistry. The Fmoc-protected amine and carboxylic acid allow the compound to be integrated into peptide sequences first, followed by orthogonal manipulations that target the aromatic motif without disturbing the peptide backbone. The resulting functionalized derivatives can serve as intermediates for fragment generation, library diversification, and fine chemical synthesis of fluorinated peptidomimetics.

5. Pharmaceutical Manufacturing Intermediates

Fmoc-alpha-Me-L-Phe(2,6-F2)-OH is applicable to pharmaceutical manufacturing workflows for producing fluorinated peptide intermediates used in process chemistry and scale-up of peptide-based chemical entities. The Fmoc carbamate provides a robust N-protection strategy compatible with industrial peptide assembly using controlled deprotection and coupling steps, while the free carboxylic acid supports reliable amide formation during chain elongation. The stereodefined L-amino acid framework and α-methyl substitution help maintain consistent structural identity across batches, which is relevant for downstream analytical characterization and impurity profiling. The difluorinated aromatic side chain enables manufacturing of well-defined fluorinated analogs that can be carried through purification, formulation development, and subsequent conversion into final peptide or peptide-like materials.

6. Analytical Research Standards

Fmoc-alpha-Me-L-Phe(2,6-F2)-OH can be used to prepare analytical research standards and reference materials for method development in peptide and amino acid analysis. The combination of Fmoc protection, an α-methyl stereocenter, and a 2,6-difluorinated phenyl ring creates a structurally distinctive signature that supports chromatographic separation and mass spectrometric identification of incorporated residues. The compound's compatibility with peptide coupling enables generation of defined peptide standards containing this residue, supporting calibration and verification for LC-MS, HPLC, and related analytical workflows. The resulting characterized peptide derivatives can function as internal or external references in studies that monitor synthesis fidelity, stereochemical integrity, and functional group integrity during peptide manufacturing and biochemical research.

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