H-DL-Asp(OMe)-OH · HCl

H-DL-Asp(OMe)-OH · HCl is a hydrochloride salt of a methyl ester of aspartic acid, presented as a racemic (DL) mixture at the α-carbon. The molecule contains an α-amino functionality in salt form, a methyl ester at the side-chain carboxyl position (Asp(OMe)), and a free carboxylic acid at the α-position, creating a dual-carboxyl protected/functionalized pattern that supports controlled peptide coupling and downstream conversion. The stereochemical mixture enables access to both enantiomeric configurations for method development, while the salt form can improve handling and facilitate reproducible derivatization steps. The ester and acid groups provide orthogonal reactivity for selective hydrolysis, activation, and transformation into peptide building blocks, chiral intermediates, or functionalized aspartate derivatives.

1. Protected Amino Acid Chemistry

H-DL-Asp(OMe)-OH · HCl is applied in protected amino acid synthesis workflows where an aspartate scaffold requires orthogonal functional group management between the α-carboxylic acid and the side-chain methyl ester. The presence of the methyl ester enables selective hydrolysis or transesterification to access Asp side-chain carboxyl derivatives without immediately perturbing the α-acid, while the amino hydrochloride form supports controlled conversion to activated coupling partners. The racemic stereochemistry supports process development and analytical method screening for ester hydrolysis/activation sequences before committing to enantioselective routes. The resulting intermediates can be carried forward into peptide building block preparation and aspartate-based functional group installation strategies.

2. Peptide Synthesis Compatibility

H-DL-Asp(OMe)-OH · HCl is suitable for peptide coupling chemistry and aspartate residue incorporation studies where side-chain ester functionality can be used as a temporary handle during chain assembly. The α-amino component (as the HCl salt) and the α-carboxylic acid allow formation of activated derivatives for amide bond construction, while the side-chain methyl ester can be retained through coupling steps and later converted to the native aspartate carboxylate. The DL configuration supports method optimization for coupling conditions and protecting-group strategies using racemic material prior to stereochemically defined synthesis. Downstream, controlled ester deprotection yields aspartate-containing peptides or peptide fragments with a defined side-chain carboxyl for further derivatization.

3. Amino Acid Derivatization

H-DL-Asp(OMe)-OH · HCl functions as a practical intermediate for amino acid derivatization and functional group transformation, leveraging the methyl ester and carboxylic acid combination. Side-chain ester chemistry can be used to generate activated carboxylates, amide/ester analogs, or targeted functionalized aspartate motifs after selective conversion of the OMe group. Salt-form amino functionality supports derivatization into N-protected formats compatible with peptide coupling and orthogonal deprotection schemes. The compound's dual-carboxyl architecture enables downstream synthesis of aspartate-based building blocks used in peptidomimetic construction and chemical biology reagent preparation.

4. Process Chemistry Intermediate

H-DL-Asp(OMe)-OH · HCl is employed in process chemistry intermediate preparation where robust handling of amino acid esters and predictable functional group interconversions are required for manufacturing-scale synthesis planning. The hydrochloride salt form can be advantageous for consistent material transfer and for reproducible conversion to activated species during route design, while the methyl ester provides a controllable protecting-group element for side-chain carboxyl functionality. The racemic nature supports bulk intermediate supply for screening and scale-up of subsequent steps, including ester conversion to acid or activation for coupling into larger molecules. The resulting downstream aspartate derivatives can serve as feedstocks for fine chemical synthesis, peptide fragment production, and industrial intermediate generation.

5. Analytical Standards And Method Development

H-DL-Asp(OMe)-OH · HCl is applicable to analytical research as a reference material for monitoring amino acid ester hydrolysis, salt-form behavior, and aspartate-related derivatization workflows. The defined structure with an α-carboxylic acid and a side-chain methyl ester enables targeted LC-MS, HPLC, and ion-pairing method development for distinguishing esterified versus acid forms and for tracking conversion during protected amino acid synthesis. The DL stereochemical mixture can be used to validate analytical separation performance and to calibrate quantitation strategies when enantiomeric resolution is not required. The compound can also support impurity profiling for ester/acid interconversion sequences that are common in peptide building block and aspartate derivative manufacturing.

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