Fmoc-L-Lys(Palm)-OH

Fmoc-L-Lys(Palm)-OH is an Fmoc-protected L-lysine derivative bearing a side-chain acyl protecting group derived from palmityl (Palm) on the ε-amino functionality. The molecule contains the canonical amino acid backbone with a stereogenic center at the α-carbon, a carbamate-linked Fmoc group on the α-amine, and a carboxylic acid suitable for peptide coupling after activation. The long-chain Palm group increases hydrophobic character and provides robust temporary masking of the ε-amine during solid-phase or solution-phase peptide assembly, while the Fmoc group supports orthogonal deprotection under standard base conditions. The resulting reactivity profile aligns with protected amino acid chemistry, enabling controlled side-chain deprotection timing and downstream functionalization of lysine-containing peptide sequences.

1. Peptide Synthesis

Fmoc-L-Lys(Palm)-OH is used in peptide building block preparation for constructing lysine-containing sequences where orthogonal protection of the α-amine and ε-amine is required. The Fmoc carbamate enables reliable N-terminal protection for stepwise peptide coupling, while the Palm group masks the lysine side-chain amine to prevent side reactions such as branching, crosslinking, or undesired ε-amide formation during chain elongation. The presence of a free carboxylic acid supports standard peptide coupling chemistry, allowing incorporation into peptides that later require ε-amino unveiling for further derivatization. Lysine side-chain availability after selective deprotection can be leveraged to generate defined cationic residues, conjugation handles, or charge-tuned peptide analogs for research-grade peptide science and method development.

2. Side-Chain Functionalization

Fmoc-L-Lys(Palm)-OH supports amino acid derivatization workflows targeting lysine ε-functionalization by providing a protected ε-amine that can be revealed on demand. The Palm-protected lysine side chain allows controlled timing of deprotection so that subsequent transformations can be performed selectively on the ε-nitrogen without perturbing the peptide N-terminus. The long hydrophobic protecting group can also be exploited to moderate solubility and minimize premature reactivity during multi-step synthesis, improving compatibility with protecting-group strategies used in peptide analog production. Downstream conversion of the ε-amino group into amide, urea, sulfonamide, or other nitrogen-containing linkages enables construction of modified peptide scaffolds used in chemical biology, molecular design, and structure-activity relationship studies.

3. Chemical Biology Conjugation

Fmoc-L-Lys(Palm)-OH is applicable to chemical biology workflows that require lysine-based conjugation chemistry with controlled site selectivity. The orthogonally protected lysine architecture provides a defined handle for later bioconjugation steps, where ε-amino exposure enables coupling to activated esters, isothiocyanates, aldehydes, or other electrophiles used to attach tags, probes, or affinity motifs. The Fmoc group supports controlled peptide assembly or fragment synthesis prior to conjugation, while the Palm group helps suppress off-target ε-reactivity during precursor generation. The resulting lysine-functionalized peptides or peptidomimetics can serve as substrates for labeling studies, receptor-binding probe development, or mapping of biomolecular interactions where nitrogen-based linkage formation is required.

4. Peptidomimetics And SAR Studies

Fmoc-L-Lys(Palm)-OH is utilized in peptidomimetic and SAR-oriented synthesis where lysine side-chain chemistry influences binding, solubility, and conformational preferences. The protected ε-amine allows introduction of defined side-chain modifications after peptide or oligomer assembly, enabling systematic variation of charge density, hydrogen-bonding capacity, and steric bulk through ε-derivatization. The Fmoc-protected α-amine ensures consistent incorporation into peptide analogs, supporting reproducible fragment construction for comparative studies. Downstream functional group transformation of the lysine side chain supports generation of analog panels for structure-activity relationship investigations and fragment-based molecular design programs that require controlled stereochemical identity and protection-group orthogonality.

5. Pharmaceutical Manufacturing Intermediates

Fmoc-L-Lys(Palm)-OH can be employed as a protected amino acid intermediate in industrial peptide manufacturing routes that demand orthogonal protection to manage lysine side-chain reactivity. The Fmoc group provides a manufacturing-compatible N-protection strategy for iterative couplings, while the Palm masking of the ε-amino group helps limit undesired branching or side reactions during scale-up of peptide synthesis. The free carboxylic acid functionality enables incorporation into larger intermediates under peptide coupling conditions, supporting downstream processing such as purification of protected intermediates and controlled deprotection steps. The resulting lysine-containing protected building blocks can be used to prepare well-defined peptide intermediates for specialty chemical production and applied peptide manufacturing workflows where reproducible protection-group behavior is required.

1. Crystal Structure of BamB from Pseudomonas aeruginosa and Functional Evaluation of Its Conserved Structural Features

2. Oleic acid and glucose regulate glucagon-like peptide 1 receptor expression in a rat pancreatic ductal cell line

3. Cationic cell-penetrating peptides are potent furin inhibitors

4. Constitutive and inflammation-dependent antimicrobial peptides produced by epithelium are differentially processed and inactivated by the commensal Finegoldia magna and the pathogen Streptococcus pyogenes

5. Olfactory receptor based piezoelectric biosensors for detection of alcohols related to food safety applications