L-3-Thiolisoleucine is an L-amino acid derivative belonging to the isoleucine family, featuring a branched aliphatic side chain bearing a sulfur-containing thioether substituent at the 3-position. The molecule contains a free amino group and a carboxyl group, with the side chain presenting a thioether functionality that can influence polarity and provide a sulfur-based chemical handle for derivatization or reactivity tuning. As a non-proteinogenic amino acid, it is used in peptide and structure-activity studies to introduce sulfur-containing side-chain character, and it can serve as a substrate building block in chemical synthesis routes that generate modified peptides or labeled analogues for analytical method development and chemical biology workflows.
CAT No: CP09402
L-3-Thiolisoleucine is an L-configured sulfur-containing amino acid featuring a chiral 3-position on the side chain and a thioether-linked thiolactone-like motif (thiolisoleucine), which provides a chemically distinct reactivity profile compared with standard aliphatic or aromatic side chains. The molecule retains the amino acid core with a primary amino functionality and a carboxylic acid group, enabling peptide coupling and controlled protection/deprotection strategies during synthesis. The sulfur atom and the thioether/thiol-associated functionality can participate in nucleophilic substitution, oxidation state adjustments, and selective derivatization to generate downstream handles for conjugation or scaffold diversification. As a chiral amino acid intermediate and peptide building block, L-3-thiolisoleucine supports stereochemically defined side-chain incorporation into peptides and can be transformed into protected or activated derivatives for synthetic organic chemistry workflows.
1. Peptide Synthesis
L-3-Thiolisoleucine serves as a side-chain functional amino acid building block for solid-phase or solution-phase peptide synthesis where a sulfur-bearing residue is required for conformational tuning and chemical reactivity. The amino acid backbone supports standard N-protection and C-terminal activation strategies, while the L-stereocenter at the 3-position preserves stereochemical fidelity during coupling and subsequent deprotections. The sulfur-containing side chain can be maintained under conditions compatible with peptide assembly and then converted to a desired oxidation state or functional group after chain elongation. Incorporation of L-3-thiolisoleucine into peptide sequences can enable access to thioether/thiol-reactive analogs used for mechanistic studies and peptide scaffold construction in amino acid chemistry.
2. Chemical Biology Probes
L-3-Thiolisoleucine can be applied in chemical biology research to introduce a sulfur-reactive side chain into peptides or small molecules used as recognition probes. The thioether/thiol-associated functionality provides a site for electrophile or oxidant-responsive transformations, enabling downstream attachment of tags for target engagement studies or pathway mapping. The amino acid core supports conjugation-compatible formats through selective protection of the amine and controlled activation of the carboxyl group to form amide or ester linkages. L-3-thiolisoleucine-derived constructs can be used to generate chemically defined biomolecular probes that reflect stereochemical side-chain effects on molecular recognition.
3. Bioconjugation Chemistry
L-3-Thiolisoleucine functions as a chiral sulfur-bearing precursor for bioconjugation workflows that require a controlled reactive handle for attaching peptides to proteins, polymers, or surfaces. The side-chain sulfur can be leveraged for site-specific derivatization, including conversion to conjugation-ready forms under orthogonal protection schemes that keep the peptide backbone intact. The amino acid functionality enables formation of stable amide bonds and facilitates incorporation into carrier peptides used for labeling strategies. L-3-Thiolisoleucine-based intermediates can support downstream linker installation and controlled conjugate generation for research-grade biomolecule modification.
4. Peptidomimetics And SAR Studies
L-3-Thiolisoleucine is suitable for peptidomimetic construction where a sulfur-containing stereodefined side chain is used to probe structure-activity relationship effects. The chiral center and sulfur-containing group can be retained or selectively transformed to modulate lipophilicity, polarizability, and potential redox sensitivity in analog libraries. The amino acid core enables systematic variation through N- and C-terminal modifications, supporting iterative synthesis of analog series for medicinal chemistry research intermediates. L-3-Thiolisoleucine-derived scaffolds can be employed to generate chemically comparable peptide analogs that support SAR studies focused on side-chain chemistry and stereochemical influence.
5. Process Chemistry Intermediate
L-3-Thiolisoleucine can be utilized as a chiral amino acid intermediate in process chemistry for manufacturing routes that require sulfur-functional stereodefined feedstocks. The presence of both amino and carboxylic acid functionalities allows conversion into protected amino acid derivatives, activated esters, or coupling-ready forms that align with scalable peptide coupling chemistry. The sulfur-containing side chain can be managed through appropriate protecting-group strategies to maintain stability during isolation, purification, and downstream transformations. L-3-Thiolisoleucine therefore supports fine chemical synthesis planning where chiral building blocks are converted into protected derivatives for consistent incorporation into larger molecular assemblies.
6. Analytical Standards And Labeling
L-3-Thiolisoleucine can be employed in analytical research as a reference material for method development involving sulfur-containing amino acid residues and peptide fragments. The defined stereochemistry and sulfur functionality support LC-MS/MS characterization and can serve as a calibration or identity standard when monitoring derivatized peptides or bioconjugates. The amino acid core enables preparation of labeled or derivatized standards through controlled N- or C-terminal chemistry, supporting reproducible detection of side-chain-modified species. L-3-Thiolisoleucine-derived analytical intermediates can thus contribute to robust characterization workflows in biochemical research and synthetic methodology assessment.
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