N-α-Benzyl-L-asparagine methyl ester hydrochloride

N-α-Benzyl-L-asparagine methyl ester hydrochloride is an L-asparagine-derived amino acid ester bearing a benzyl-protected α-amino group and a methyl ester at the carboxyl terminus, with hydrochloride salt formation that supports handling of the basic sites. The side chain contains a primary amide characteristic of asparagine chemistry, enabling selective functional-group transformations and amide-preserving peptide coupling strategies. The stereogenic center at the α-position retains L-configuration, which is relevant for stereocontrolled peptide bond formation and for maintaining native-like backbone geometry in downstream analogs. The benzylic N-protection and ester functionality provide orthogonal reactivity patterns for sequential deprotection, conversion to activated carboxylic derivatives, and incorporation into peptide fragments or as a chiral intermediate in fine chemical synthesis.

1. Protected Amino Acid Synthesis

N-α-Benzyl-L-asparagine methyl ester hydrochloride supports protected amino acid synthesis workflows where orthogonal protection of the α-amino group and temporary ester masking of the carboxyl group are required for controlled coupling chemistry. The benzyl-protected nitrogen can be carried through ester-mediated intermediate steps while remaining compatible with standard peptide coupling conditions after conversion of the methyl ester to an activated carboxylate. The L-asparagine side-chain amide can remain intact during peptide fragment assembly, enabling downstream conversion to aspartamide-like motifs or retention for amide-based hydrogen bonding in analog libraries. Hydrochloride salt formation can improve operational stability during handling and can facilitate reproducible deprotection and activation sequences in synthetic planning for amino acid derivative preparation.

2. Peptide Synthesis Building Block

N-α-Benzyl-L-asparagine methyl ester hydrochloride functions as a peptide building block precursor for constructing asparagine-containing sequences in solid-phase or solution-phase peptide synthesis. The protected α-amino group (N-benzyl) and esterified carboxyl group allow preparation of coupling-ready fragments by transforming the methyl ester into an activated acid derivative while maintaining the stereochemical integrity of the L-α-center. The side-chain primary amide participates in peptide analog design by providing polar functionality that can influence solubility, secondary structure propensity, and intermolecular recognition in peptide scaffolds. Benzyl protection provides a practical deprotection handle, enabling generation of the free α-amine at the appropriate stage to support sequential chain elongation and controlled assembly of protected peptide intermediates.

3. Side-Chain Functionalization

N-α-Benzyl-L-asparagine methyl ester hydrochloride can be applied in side-chain functionalization programs that leverage the asparagine primary amide for targeted derivatization while preserving the α-backbone for further synthetic elaboration. The side-chain amide can be converted into alternative carbonyl-containing motifs or used as a handle for subsequent transformations that generate peptidomimetic features, hydrogen-bonding patterns, or polarity-tuned analogs. The N-benzyl protection and methyl ester masking enable selective chemistry at the side chain under conditions that avoid premature loss of the coupling-ready backbone functionalities. Downstream derivatives prepared from this intermediate can serve as research-grade reagents for structure-activity relationship studies, molecular recognition probes, and scaffold diversification in amino acid chemistry and peptide science.

4. Chiral Intermediate For Derivatization

N-α-Benzyl-L-asparagine methyl ester hydrochloride serves as a chiral amino acid intermediate for stereocontrolled synthesis of asparagine-based derivatives used in fine chemical production and synthetic organic chemistry. The maintained L-configuration at the α-carbon supports predictable stereochemical outcomes when the ester is converted to carboxyl-activated intermediates or when the α-amino group is liberated for further coupling steps. The combination of N-benzyl protection and methyl ester functionality provides a controlled reactivity profile that can be integrated into multi-step manufacturing routes for protected amino acid derivatives, peptide fragments, and chiral building blocks. The hydrochloride salt form can support consistent handling during scale-up of intermediate preparation where salt formation improves reproducibility of material transfer and downstream conversion steps.

5. Chemical Biology And Conjugation Chemistry

N-α-Benzyl-L-asparagine methyl ester hydrochloride can be utilized in chemical biology contexts where asparagine-like polar motifs and amide-bearing side chains are required for conjugation-compatible building blocks. The side-chain amide and the protected α-amino functionality enable staged modification strategies, including conversion of the carboxyl terminus to activated derivatives for attachment to linkers, tags, or biomolecule-reactive handles. The benzyl-protected nitrogen can be managed to control when the free amine becomes available, supporting selective conjugation timing relative to other functional groups on a target scaffold. Downstream conjugation products derived from this intermediate can support biomolecule labeling, probe construction, and peptide-based reagent generation for biochemical research workflows that require defined stereochemistry and preserved amide functionality.

1. Oleic acid and glucose regulate glucagon-like peptide 1 receptor expression in a rat pancreatic ductal cell line

2. SERS spectrum of the peptide thymosin‐β4 obtained with Ag nanorod substrate

3. C-Peptide replacement therapy and sensory nerve function in type 1 diabetic neuropathy

4. Odorant binding protein based biomimetic sensors for detection of alcohols associated with Salmonella contamination in packaged beef

5. Myotropic activity of allatostatins in tenebrionid beetles