Boc-Thr(p-chloro-Bzl)-OH · DCHA

Boc-Thr(p-chloro-Bzl)-OH · DCHA is a Boc-protected threonine derivative bearing a side-chain benzyl ether substituted with p-chloro on the benzyl group, presented as a dicyclohexylamine salt (DCHA) that improves handling and crystallinity for synthetic use. The molecule contains a single stereogenic center at the threonine α-carbon, with the protected amino functionality arranged for controlled peptide coupling after deprotection. The Boc carbamate masks the amine while the benzyl-protected hydroxyl and the p-chloro benzyl group introduce an aromatic, electron-withdrawing handle that can modulate reactivity during downstream transformations. The salt form and the combination of protected functional groups make the compound a practical chiral amino acid building block and intermediate for peptide synthesis, peptidomimetic construction, and side-chain functionalization workflows.

1. Peptide Synthesis

Boc-Thr(p-chloro-Bzl)-OH · DCHA supports peptide building block preparation in solid-phase or solution-phase assembly where orthogonal protection is required. The Boc carbamate enables amide bond formation after Boc removal, while the benzyl-protected threonine hydroxyl prevents side-chain participation during coupling and subsequent chain elongation. The p-chloro benzyl ether provides an aromatic substituent that can be retained through multiple synthetic steps and later unmasked or transformed depending on the deprotection strategy. Downstream peptide analogs can incorporate this residue to tune sterics and electronics around the threonine side chain, supporting systematic peptide construction for biochemical research and SAR studies. The chiral threonine backbone ensures stereochemical fidelity during peptide coupling chemistry.

2. Side-Chain Functionalization

Boc-Thr(p-chloro-Bzl)-OH · DCHA is suitable for side-chain functionalization routes that begin from an O-benzyl-protected threonine motif. The benzyl ether with a para-chloro substituent acts as a protected hydroxyl group while simultaneously introducing a chlorinated aromatic handle that can participate in later derivatization, such as conversion to alternative benzyl-based protecting groups, aromatic substitution chemistry, or controlled deprotection to reveal the free threonyl alcohol. The presence of the Boc group allows selective manipulation of the side chain without premature amide formation, enabling stepwise synthesis of functionalized amino acid derivatives. Resulting intermediates can be used to generate threonine-containing peptidomimetics, kinase-binding motifs, or conformationally constrained analogs where side-chain geometry and aromatic electronics matter. The salt form can further facilitate reproducible weighing, dissolution behavior, and intermediate handling in multi-step synthesis.

3. Chiral Amino Acid Intermediate

Boc-Thr(p-chloro-Bzl)-OH · DCHA functions as a chiral amino acid intermediate for stereoselective synthesis and protected amino acid chemistry. The defined α-stereocenter of threonine, combined with orthogonal protection of the amine (Boc) and hydroxyl (p-chloro benzyl ether), enables downstream transformations that preserve stereochemical integrity while allowing controlled functional group interconversions. The aromatic p-chloro benzyl group can be leveraged as a stable protecting group element during chiral derivatization sequences, including preparation of C-terminal modified derivatives or incorporation into longer peptide fragments. The dicyclohexylamine salt form can be advantageous for scalable intermediate preparation where consistent physical properties support process chemistry workflows. This makes the compound applicable to chiral building block design for fine chemical synthesis and peptide science.

4. Bioconjugation Chemistry

Boc-Thr(p-chloro-Bzl)-OH · DCHA can be applied to bioconjugation chemistry workflows that require threonine-derived linkers with protected functional groups during reagent synthesis. The protected threonine hydroxyl and Boc-protected amine allow the compound to be processed into conjugation-ready amino acid derivatives while preventing undesired coupling or crosslinking during intermediate handling. The para-chloro benzyl aromatic substituent can serve as a structural element for constructing defined linkers that later undergo deprotection to expose a reactive alcohol for coupling chemistries such as esterification or ether-based attachment strategies. The chiral threonine core can be incorporated into peptide conjugates to influence solubility, spacing, and local conformation around the attachment point. Downstream conjugate synthesis benefits from the orthogonal protection pattern that separates amine activation from side-chain unmasking.

5. Pharmaceutical Intermediate Preparation

Boc-Thr(p-chloro-Bzl)-OH · DCHA is relevant to pharmaceutical intermediate preparation where protected amino acids are used to assemble peptide-like scaffolds and stereochemically defined fragments. The Boc-protected amine supports controlled coupling chemistry to form amide bonds while the benzyl ether protects the threonine hydroxyl from premature reactions under coupling and purification conditions. The p-chloro benzyl substituent provides an aromatic motif that can be retained in candidate molecules or converted during later synthetic stages to modulate polarity and binding-site interactions in structure-activity relationship studies. The salt form with dicyclohexylamine can be leveraged for practical manufacturing handling of chiral intermediates, supporting consistent feedstock preparation for downstream synthesis. The compound therefore serves as a process-compatible chiral building block for producing threonine-containing fragments used in medicinal chemistry and specialty chemical manufacturing.

6. Process Chemistry Intermediate

Boc-Thr(p-chloro-Bzl)-OH · DCHA aligns with process chemistry intermediate needs that emphasize stable, isolable protected amino acid forms. The combination of Boc protection and benzyl ether protection enables predictable reactivity control across multi-step sequences, reducing side reactions from free amine or alcohol functionalities during intermediate preparation. The p-chloro benzyl group can contribute to crystallinity and handling characteristics, while the DCHA salt form often improves physical robustness for filtration and isolation operations in synthetic manufacturing contexts. The chiral threonine framework allows incorporation into larger peptide building blocks with stereochemical consistency, supporting scalable fine chemical synthesis of protected fragments. The compound can be employed as a reliable input for downstream peptide coupling chemistry, peptidomimetic construction, and intermediate generation for industrial chemical production.

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