H-L-Lys(Fmoc)-OH is an Fmoc-protected lysine derivative in which the side chain is a basic ε-aminomethyl group and the α-amino and α-carboxyl functionalities are present on the amino acid backbone, with the α-amino protected by the Fmoc group. The molecule bears the fluorenylmethoxycarbonyl (Fmoc) protecting group on the amino functionality to control chemoselectivity during peptide assembly, while the lysine side chain remains as a free ε-amino group capable of forming salt or participating in amide bond formation after appropriate activation. H-L-Lys(Fmoc)-OH is used as a protected amino acid building block for stepwise peptide synthesis and for preparing lysine-containing peptide intermediates where orthogonal handling of the ε-amino side chain is required.
CAT No: CP26070
CAS No:84624-28-2
Chemical Name:N-epsilon-(9-Fluorenylmethyloxycarbonyl)-L-lysine
H-L-Lys(Fmoc)-OH is an Fmoc-protected L-lysine derivative in which the α-amino group is masked with a fluorenylmethoxycarbonyl (Fmoc) carbamate, while the ε-amino side chain remains unprotected and available for further functionalization. The molecule contains a free carboxylic acid for C-terminal compatibility and a stereogenic center at the lysine α-carbon, preserving the L-configuration required for stereochemically controlled peptide synthesis. The Fmoc group provides base-labile protection that can be removed under standard peptide-manufacturing conditions, exposing the α-amine for coupling without disturbing the ε-amino functionality. The presence of a primary side-chain amine enables selective derivatization, salt formation, and orthogonal protection strategies that support downstream peptide analog construction and biochemical probe development.
1. Protected Amino Acids
H-L-Lys(Fmoc)-OH is used in protected amino acid synthesis and peptide building block preparation where orthogonal functional group handling is required. The Fmoc-protected α-amino group supports stepwise peptide coupling, while the free ε-amino side chain can be protected or modified to tune chemoselectivity during chain assembly. The carboxylic acid enables direct activation for amide bond formation, supporting compatibility with common peptide coupling chemistries used in research and manufacturing workflows. Downstream use frequently includes preparing lysine-containing peptide fragments, generating N-terminally protected lysine units, and enabling controlled deprotection/coupling sequences for stereochemically defined products in amino acid chemistry.
2. Peptide Synthesis
H-L-Lys(Fmoc)-OH is applied in solid-phase peptide synthesis and related peptide construction strategies that rely on Fmoc deprotection and selective amide formation. The Fmoc carbamate masks the α-amine to prevent premature side reactions, while the unprotected ε-amino group can participate in controlled side-chain chemistry when orthogonally protected or selectively acylated. The L-lysine backbone stereochemistry supports incorporation into peptides with defined spatial presentation of the lysine side chain, which is often critical for sequence-dependent structure and binding motifs. The resulting lysine-containing peptide intermediates can be extended, cyclized, or converted into peptidomimetics, supporting peptide science from fragment assembly to larger synthetic targets.
3. Side-Chain Functionalization
H-L-Lys(Fmoc)-OH is suitable for side-chain functionalization workflows in chemical biology and synthetic organic chemistry that exploit the free ε-amino group. The primary amine can undergo acylation, sulfonylation, carbamate formation, or reductive amination to install handles such as linkers, affinity tags, or reactive groups for subsequent conjugation steps. The Fmoc-protected α-amine provides a stable differentiation point, allowing side-chain modification without disrupting the peptide-compatible N-protection state. Downstream derivative formation can include lysine-based conjugates, labeled peptide analogs, and intermediate preparation for constructing biomolecule-targeting scaffolds with controlled functional group density.
4. Bioconjugation Chemistry
H-L-Lys(Fmoc)-OH is used in bioconjugation chemistry and biomolecule modification efforts where lysine side chains serve as conjugation sites or anchoring points. The ε-amino functionality enables coupling to activated esters, isothiocyanates, aldehyde-derived linkers, or other electrophilic reagents to generate stable amide or related linkages under conditions compatible with peptide-derived materials. The Fmoc-protected α-carboxyl/amine framework supports preparation of conjugatable peptide fragments that can be incorporated into larger constructs before or after conjugation, depending on the orthogonal protection strategy. Downstream applications include preparing labeled peptides for analytical research, generating conjugate libraries for molecular recognition studies, and producing intermediate materials for multistep assembly of functional biomolecule derivatives.
5. Pharmaceutical Manufacturing
H-L-Lys(Fmoc)-OH is employed in pharmaceutical manufacturing contexts as a peptide synthesis intermediate for producing lysine-containing peptide intermediates and peptidomimetic building blocks. The Fmoc protection strategy aligns with scalable, stepwise synthesis logic, where base-labile deprotection can be paired with controlled coupling operations to build defined sequences. The free ε-amino group allows introduction of side-chain chemistry that can be tuned for solubility, stability, or downstream formulation-relevant properties, provided orthogonal protection is selected to match the process sequence. Industrial utility also extends to preparing chiral amino acid derivatives and protected lysine fragments used in fine chemical production, where consistent stereochemistry and functional group compatibility support reliable downstream conversion to final peptide-related materials.
6. Analytical Research
H-L-Lys(Fmoc)-OH is applied in analytical research and method development where defined lysine-containing standards or internal references are needed for peptide and amino acid analysis. The combination of a carboxylic acid and an Fmoc-protected α-amine supports predictable behavior during derivatization, chromatographic separation, and mass spectrometric detection of peptide-like analytes. The unprotected ε-amino group can be used to generate labeled or derivatized forms that improve detectability or enable targeted assay formats for amino acid derivative quantitation. Downstream use includes preparing calibration materials, supporting characterization of peptide coupling outcomes, and serving as a chiral starting point for constructing analytical probes and reference compounds in applied peptide chemistry.
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