H-D-Asp(OMe)-OH · HCl

H-D-Asp(OMe)-OH · HCl is the hydrochloride salt of methyl esterified D-aspartic acid, featuring the D-configured α-amino acid backbone with a side-chain carboxyl group protected as a methyl ester (Asp(OMe)) and a free carboxylic acid at the α-position (-CO2H). The N-terminus is acetylated as an N-acetyl (H-D-Asp(OMe)-OH indicates the amino functionality is present as an acylated residue), while the esterified side chain introduces a controlled electrophilic carbonyl for subsequent functional group interconversions. The presence of the HCl salt form increases handling stability and solubility during peptide-coupling and intermediate preparation workflows. The combination of stereogenic D-configuration, orthogonally addressable carbonyl functionalities (α-acid and side-chain ester), and acid salt behavior makes the compound suitable as a chiral amino acid intermediate for protected amino acid synthesis and downstream peptide or peptidomimetic construction.

1. Peptide Synthesis

H-D-Asp(OMe)-OH · HCl supports peptide building block preparation where D-aspartate stereochemistry is required for β-peptide analogs, protease-resistant sequences, or stereochemically defined peptide fragments. The α-carboxylic acid and N-acylated amino functionality enable conversion into activated coupling derivatives, while the side-chain methyl ester can be retained during chain assembly and later transformed to the corresponding carboxylic acid for native-like Asp side-chain presentation. The orthogonal carbonyl pattern facilitates selective deprotection or hydrolysis strategies to control when the side-chain becomes reactive for salt formation, ion pairing, or further derivatization. Downstream peptide coupling compatibility makes the compound applicable to solid-phase or solution-phase workflows aiming at defined D-Asp incorporation and controlled side-chain functionality.

2. Amino Acid Derivatization

H-D-Asp(OMe)-OH · HCl functions as a chiral precursor for amino acid derivatization and functional group interconversion, leveraging the methyl ester side chain as a handle for controlled transformations. The D-configuration provides stereochemical fidelity for generating D-Asp-containing derivatives used in chiral synthesis, stereochemical probes, and non-proteinogenic scaffold construction. The ester group can be converted to carboxylic acid, activated for amide formation, or used as a temporary protection element during multi-step syntheses that also involve α-functionalization. The hydrochloride salt form can improve reproducibility in intermediate preparation and can be carried through to downstream coupling or derivatization steps where salt-controlled solubility supports process consistency.

3. Peptidomimetic Construction

H-D-Asp(OMe)-OH · HCl is suitable for peptidomimetic construction where controlled placement of an aspartate side chain and stereochemical inversion relative to L-Asp is required for receptor-binding studies or enzyme selectivity profiling. The methyl ester side chain provides a protected carbonyl that can be manipulated to generate carboxylate-bearing motifs, cyclic constraints, or side-chain-linked heterocycles after peptide or scaffold assembly. The N-acylated amino acid framework supports incorporation into amide-rich backbones while maintaining orthogonal functional group timing for later oxidation, reduction, or hydrolysis steps. The resulting D-Asp-containing intermediates can be used to generate chemically defined analog libraries that support structure-activity relationship studies and molecular recognition investigations.

4. Pharmaceutical Intermediate Preparation

H-D-Asp(OMe)-OH · HCl can be employed as a process chemistry intermediate for the manufacture of D-aspartate-derived fragments used in synthetic routes to enzyme inhibitors, peptidomimetic leads, and stereodefined building blocks. The compound's D-aspartate architecture and ester/acid differentiation allow stepwise functional group management, enabling selective activation of the α-carboxyl group while deferring side-chain acid exposure until the appropriate stage. Hydrochloride salt formation supports handling in industrial fine chemical synthesis where consistent salt behavior can simplify isolation and downstream conversion to coupling-ready derivatives. The compound's role as a chiral amino acid intermediate aligns with industrial manufacturing needs for reproducible stereochemistry and predictable functional group reactivity.

5. Analytical Research Standards

H-D-Asp(OMe)-OH · HCl is applicable to analytical research where D-Asp-containing standards or calibration materials are needed to verify stereochemical outcomes in amino acid derivatization and peptide coupling chemistry. The methyl ester side chain and free α-carboxylic acid provide distinct chromatographic and spectroscopic signatures that can help distinguish D- from L-aspartate derivatives and monitor ester hydrolysis or deprotection states. The hydrochloride salt form can improve reproducibility of sample preparation for LC-MS or derivatization-based assays that require consistent ionization behavior. The compound can also serve as a reference intermediate for method development in quantifying protected amino acid intermediates and confirming functional group integrity during peptide building block synthesis.

1. Tachykinin-related peptides modulate immune-gene expression in the mealworm beetle Tenebrio molitor L

2. Sex differences in oxidative stress level and antioxidative enzymes expression and activity in obese pre-diabetic elderly rats treated with metformin or liraglutide

3. Relatedness of antibodies to peptides containing homocitrulline or citrulline in patients with rheumatoid arthritis

4. GLP-1, exendin-4 and C-peptide regulate pancreatic islet microcirculation, insulin secretion and glucose tolerance in rats

5. Zeta-potential-changing nanoparticles conjugated with cell-penetrating peptides for enhanced transfection efficiency