DL-3-Thiolisoleucine is a non-proteinogenic, sulfur-containing amino acid analogue featuring a branched aliphatic framework and a thioether substituent at the 3-position relative to the amino acid backbone. The molecule contains both an amino group and a carboxyl group, and the "DL" designation indicates a racemic mixture of stereoisomers at the stereogenic center, which can influence incorporation outcomes in peptide synthesis. As an amino acid building block, it is used in peptide and structure-activity studies where a thioether side chain provides a distinct chemical environment for conformational effects, chemical labeling strategies, or downstream derivatization of sulfur-containing functionality.
CAT No: CP09401
DL-3-Thiolisoleucine is a thioether-containing amino acid derivative featuring a chiral 3-position on the amino acid backbone and a side chain that incorporates a thiolisoleucine motif (thioether sulfur within an isoleucine-like carbon framework). The molecule bears the amino and carboxyl functionality typical of amino acid intermediates, with the side-chain sulfur providing distinct nucleophilicity and coordination behavior relative to purely hydrocarbon amino acids. The DL designation indicates a racemic mixture at the stereogenic center, which is relevant for stereochemical control in peptide coupling, chiral resolution workflows, and downstream assay interpretation. The thioether side chain can participate in selective functional transformations, including oxidation to sulfoxide/sulfone analogs or conversion to more reactive sulfur derivatives, making the compound a practical chiral amino acid intermediate and side-chain functionalization precursor.
1. Peptide Synthesis
DL-3-Thiolisoleucine is applied in peptide building workflows where a sulfur-bearing side chain is required for native or engineered peptide architectures. The amino acid backbone supports standard peptide coupling chemistry, while the thioether side chain can be retained as a stable sulfur handle or transformed after assembly to generate oxidation-state variants. Racemic stereochemistry can be leveraged for preliminary structure-activity relationship studies or for generating libraries where stereochemical effects are resolved later using chiral separation or stereospecific downstream steps. Peptides incorporating sulfur-functional side chains can then be used to probe conformational preferences, oxidation sensitivity, and side-chain-mediated interactions in biochemical research.
2. Side-Chain Functionalization
DL-3-Thiolisoleucine is suitable for synthetic organic chemistry routes that target sulfur chemistry for post-modification of amino acid derivatives. The thioether sulfur provides a reactive functional site for controlled oxidation to sulfoxide or sulfone analogs, enabling tuning of polarity, hydrogen-bond acceptor strength, and metal-binding behavior. The amino acid framework can be protected and deprotected as needed to maintain coupling compatibility while selective sulfur transformations proceed on the side chain. Downstream derivatives can serve as intermediates for peptidomimetic construction, conformational probes, or electrophile/ligand precursors derived from sulfur oxidation states.
3. Chiral Resolution Studies
DL-3-Thiolisoleucine is used as a chiral amino acid intermediate in workflows that evaluate stereochemical influence on peptide coupling, chromatographic behavior, and downstream structure-function outcomes. The presence of a single stereogenic center at C-3 means enantiomer separation can be performed to generate defined L- or D-enantiomers for stereochemically controlled synthesis. The thioether side chain can also influence chiral recognition during resolution, affecting salt formation, derivatization, or chromatographic selectivity. Isolated enantiomers can then be incorporated into protected amino acid synthesis and peptide building block preparation for stereodefined studies in chemical biology and medicinal chemistry research.
4. Chemical Biology Probes
DL-3-Thiolisoleucine is employed in chemical biology research where sulfur-containing side chains act as handles for molecular recognition and redox-sensitive labeling strategies. The thioether functionality can be oxidized or further derivatized to introduce functional groups that participate in binding, affinity capture, or bioconjugation-compatible chemistries after appropriate protection management. The amino acid backbone enables incorporation into peptides or peptide-like scaffolds used for probing protein interactions, mapping binding pockets, or generating substrate analogs for enzyme studies. Racemic material can support screening-stage experiments, with stereochemically defined analogs prepared subsequently to interpret stereoselective binding or processing.
5. Pharmaceutical Intermediate Preparation
DL-3-Thiolisoleucine is applicable to fine chemical synthesis and pharmaceutical intermediate preparation where sulfur-bearing amino acid derivatives are required for medicinal chemistry programs and peptidomimetic scaffolds. The amino and carboxyl functionalities support conversion into protected amino acid forms and coupling-ready derivatives, while the side-chain sulfur can be carried through synthesis as a stable thioether or converted into more polar oxidation-state variants during route design. The DL racemate can be used for process development studies that assess impurity profiles, conversion behavior, and downstream chiral separation feasibility. Resulting intermediates can feed into larger synthetic sequences that generate sulfur-modified building blocks for drug-discovery chemistry and related industrial manufacturing operations.
6. Analytical Research Standards
DL-3-Thiolisoleucine is suitable for analytical research and method development where sulfur-containing amino acid derivatives serve as reference materials for chromatography, derivatization, and mass spectrometric identification. The thioether side chain provides a distinct chemical signature that can be exploited through oxidation-based derivatization or targeted detection of sulfur-containing fragments. Racemic composition enables evaluation of enantiomeric separation methods and supports validation of chiral HPLC/UPLC workflows when paired with appropriate chiral selectors. Prepared standards of DL-3-Thiolisoleucine and its oxidation-state derivatives can support quality control of amino acid intermediates, peptide building block lots, and downstream sulfur-functional products in applied synthetic chemistry.
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