H-D-Trp-OBzl · HCl

H-D-Trp-OBzl · HCl is a hydrochloride salt of an N-protected D-tryptophan benzyl ester, featuring a D-configured chiral center at the amino acid backbone and an indole side chain capable of aromatic and electrophilic substitution chemistry. The benzyl ester (OBzl) masks the carboxylate as a removable protecting group, while the N-terminal protection as H-D-Trp- indicates an amino functionality suited for controlled peptide coupling logic after appropriate activation or salt handling. The indole nitrogen and aromatic π-system enable downstream derivatization routes, including selective functionalization that preserves stereochemical integrity of the D-tryptophan scaffold. Salt formation with HCl improves handling and can modulate reactivity of the amino-derived functionality during protected amino acid synthesis and peptide-building workflows.

1. Peptide Synthesis

H-D-Trp-OBzl · HCl is applied in peptide synthesis as a D-tryptophan benzyl ester peptide building block where stereochemical inversion relative to L-tryptophan can be intentionally introduced into peptide sequences. The indole side chain remains protected from undesired aliphatic transformations while the benzyl ester supports C-terminal protection compatible with standard coupling strategies and subsequent ester cleavage when generating a free carboxyl terminus. The D-configuration enables incorporation into retro-inverso and stereochemically constrained peptide analogs, supporting studies of backbone chirality effects on conformational preferences and proteolytic stability. The hydrochloride form can facilitate reproducible handling of the amino acid derivative during protected amino acid assembly and downstream purification of peptide intermediates.

2. Peptidomimetics And SAR

H-D-Trp-OBzl · HCl supports peptidomimetic construction and structure-activity relationship studies by providing a chiral D-tryptophan unit with an indole aromatic pharmacophore for scaffold diversification. The benzyl ester enables C-terminal masking during iterative analog synthesis, while the indole ring can participate in electrophilic substitution or cross-coupling-compatible functionalization to generate substituted tryptophan mimetics. Stereochemical control from the D-center helps align molecular recognition elements in assays that probe how side-chain orientation and backbone chirality influence binding or activity trends. The resulting D-tryptophan-containing analogs can serve as SAR intermediates for rapid library generation and subsequent derivatization toward more stable or conformationally restricted peptide-like molecules.

3. Unnatural Amino Acid Incorporation

H-D-Trp-OBzl · HCl is suitable for unnatural amino acid incorporation workflows in chemical biology and protein engineering contexts where D-amino acid incorporation is used to modulate folding, resistance to proteases, or binding-site geometry. The protected benzyl ester and N-protection strategy allow the compound to be handled as a defined chiral building block that can be incorporated into larger constructs while minimizing premature hydrolysis or side reactions. The indole functionality can be retained for later functional group transformations, such as introducing substituents that tune polarity, hydrogen-bonding capacity, or aromatic stacking interactions. Downstream derivatives produced from this chiral intermediate can be used to generate D-tryptophan-containing proteins, peptide conjugates, or engineered biomolecular probes for mechanistic studies.

4. Side-Chain Functionalization

H-D-Trp-OBzl · HCl is employed in side-chain functionalization chemistry leveraging the indole aromatic system to access substituted D-tryptophan derivatives while maintaining the protected amino acid framework. The benzyl ester provides a stable handle for selective transformations on the indole ring without simultaneously exposing a free carboxylate that could interfere with electrophilic or oxidative conditions. The D-configuration ensures that stereochemical outcomes remain consistent across a series of indole-substituted analogs, supporting reproducible structure-function comparisons. Functionalized products derived from this intermediate can feed into peptidomimetic libraries, receptor-binding probes, and analytical standards where controlled indole substitution patterns are required.

5. Pharmaceutical Intermediate Preparation

H-D-Trp-OBzl · HCl is relevant to pharmaceutical intermediate preparation and fine chemical synthesis as a chiral D-tryptophan derivative used to build stereodefined fragments for peptide-like or indole-containing small molecules. The protected ester form supports manufacturing-oriented handling by reducing carboxylate reactivity during multistep synthesis, while the indole motif provides a chemically tractable aromatic core for subsequent elaboration. The hydrochloride salt can assist in consistent material handling and can be integrated into process chemistry sequences that require controlled exposure of functional groups for coupling, deprotection, or conversion to more reactive intermediates. Downstream, the compound can be converted into C-terminally functionalized D-tryptophan units that serve as inputs for larger assembly steps in industrial-scale synthesis of specialty intermediates.

6. Analytical Research Standards

H-D-Trp-OBzl · HCl is utilized in analytical research as a stereochemically defined D-tryptophan ester standard for method development, impurity profiling, and LC/GC-MS reference material preparation. The benzyl ester and indole aromatic features provide characteristic fragmentation patterns and retention behavior that can support identification of D-tryptophan-containing species in complex peptide matrices. The hydrochloride salt form can improve reproducibility of sample preparation and can help maintain consistent physicochemical behavior during derivatization or extraction steps. Analytical workflows can employ this compound as a calibration or comparison reference for protected amino acid synthesis monitoring, peptide coupling optimization studies, and verification of stereochemical incorporation in D-amino acid-containing products.

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

2. Myotropic activity and immunolocalization of selected neuropeptides of the burying beetle Nicrophorus vespilloides (Coleoptera: Silphidae)

3. Low bone turnover and low BMD in Down syndrome: effect of intermittent PTH treatment

4. Genetic, cellular, and structural characterization of the membrane potential-dependent cell-penetrating peptide translocation pore

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