H-Gln(isopropyl)-OH

H-Gln(isopropyl)-OH is a glutamine-derived amino acid derivative featuring a free carboxylic acid and an N-substituted amide side chain consistent with the Gln scaffold, where the alpha-amino group is acylated with an isopropyl group (N-isopropyl protected or masked amine character depending on synthetic context). The molecule retains the stereochemically defined glutamine backbone, providing a chiral center at the alpha carbon that can be carried through peptide coupling sequences with stereochemical integrity. The side-chain amide functionality supports hydrogen-bonding interactions and can participate in derivatization strategies after appropriate activation or protection-state adjustment. The N-isopropyl substitution modulates nucleophilicity and can be used to tune chemoselectivity during peptide building block preparation, downstream functional group transformations, and chiral intermediate handling.

1. Protected Amino Acids

H-Gln(isopropyl)-OH is suitable for protected amino acid synthesis workflows where controlled amine reactivity is needed during peptide building block preparation. The N-isopropyl substitution reduces direct amine nucleophilicity while the free carboxylic acid enables conversion to activated coupling derivatives for amide bond formation. The glutamine side-chain amide remains present for later functionalization or for incorporation into peptide sequences that require side-chain hydrogen-bonding. Protection-state tuning using N-alkyl masking can support selective coupling, intermediate isolation, and planned deprotection steps in peptide chemistry and chiral amino acid intermediate manufacturing.

2. Peptide Synthesis

H-Gln(isopropyl)-OH is applicable to peptide coupling chemistry as a glutamine-containing amino acid building block precursor for constructing peptide bonds at the alpha-carboxyl functionality. The chiral glutamine backbone provides the stereochemical information required for incorporation into peptides with defined spatial arrangement at the residue level. The side-chain amide can contribute to intramolecular and intermolecular hydrogen-bond networks in the growing peptide, affecting solubility and conformational preferences during synthesis and purification. N-isopropyl substitution can be employed to manage chemoselectivity during iterative coupling cycles and to prepare downstream derivatives for peptide analog construction and fragment assembly.

3. Chemical Biology Conjugation

H-Gln(isopropyl)-OH can be used in chemical biology research and biomolecule modification programs where glutamine-like side-chain chemistry supports targeted conjugation strategies. The free carboxylic acid enables formation of activated esters or amide linkers that can connect the amino acid residue to linkers, probes, or scaffold molecules. The side-chain amide offers an additional handle for hydrogen-bond-mediated recognition and can be retained during conjugation to maintain structural mimicry of glutamine motifs. N-alkyl masking at the amino terminus can help control coupling selectivity, supporting the preparation of amino acid-based intermediates for labeling, affinity reagent synthesis, and structure-defined conjugate generation.

4. SAR Studies

H-Gln(isopropyl)-OH is relevant to structure-activity relationship studies that require glutamine residue incorporation into peptidomimetic or constrained analog libraries. The defined stereochemistry at the alpha carbon supports consistent spatial presentation of the backbone geometry across analog series. The side-chain amide enables systematic modulation of polarity and hydrogen-bonding capacity, which can be used to probe receptor or binding-site interactions in SAR workflows. The N-isopropyl substitution provides a controllable protection-state variable that can be adjusted to match the coupling chemistry and downstream functional group transformations used to generate analogs for analytical screening and molecular design.

5. Process Chemistry Intermediate

H-Gln(isopropyl)-OH is suitable as a process chemistry intermediate for fine chemical synthesis routes that require glutamine-derived chiral building blocks with managed amine reactivity. The combination of a free carboxylic acid and an N-isopropyl substituted amino group supports stepwise conversion into coupling-ready forms while limiting undesired side reactions associated with unmasked amines. The glutamine side-chain amide can be carried through manufacturing sequences as a stable functional group under appropriately selected activation conditions, enabling predictable downstream incorporation into peptide intermediates. The stereochemically defined amino acid framework supports scalable preparation of peptide building blocks and amino acid derivatives used in industrial chemical manufacturing and applied research supply chains.

1. Immune responses to homocitrulline-and citrulline-containing peptides in rheumatoid arthritis

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

3. Proinsulin C-peptide and insulin: Limited pattern similarities of interest in inter-peptide interactions but no C-peptide effect on insulin and IGF-1 receptor signaling

4. A possible role of tachykinin-related peptide on an immune system activity of mealworm beetle, Tenebrio molitor L

5. Spatiotemporal delivery of nanoformulated liraglutide for cardiac regeneration after myocardial infarction