Laminarin, a complicated polysaccharide originating from brown algae, has emerged as a compelling candidate in the domain of biomedical research.

Gelatin methacryloyl (GelMA) hydrogels have gained significant recognition as versatile biomaterials in the biomedical domain. GelMA hydrogels emulate vital characteristics of the innate extracellular matrix by integrating cell-adhering and matrix metalloproteinase-responsive peptide motifs. These features enable cellular proliferation and spreading within GelMA-based hydrogel scaffolds. Moreover, GelMA displays flexibility in processing, as it experiences crosslinking when exposed to light irradiation, supporting the development of hydrogels with adjustable mechanical characteristics. The drug delivery landscape has been reshaped by GelMA hydrogels, offering a favorable platform for the controlled and sustained release of therapeutic actives. The tunable physicochemical characteristics of GelMA enable precise modulation of the kinetics of drug release, ensuring optimal therapeutic effectiveness. In tissue engineering, GelMA hydrogels perform an essential role in the design of the scaffold, providing a biomimetic environment conducive to cell adhesion, proliferation, and differentiation. Incorporating GelMA in three-dimensional printing further improves its applicability in drug delivery and developing complicated tissue constructs with spatial precision. Wound healing applications showcase GelMA hydrogels as bioactive dressings, fostering a conducive microenvironment for tissue regeneration. The inherent biocompatibility and tunable mechanical characteristics of GelMA provide its efficiency in the closure of wounds and tissue repair. GelMA hydrogels stand at the forefront of biomedical innovation, offering a versatile platform for addressing diverse challenges in drug delivery, tissue engineering, and wound healing. This review provides a comprehensive overview, fostering an in-depth understanding of GelMA hydrogel’s potential impact on progressing biomedical sciences.

A novel hybrid synthetic approach was developed for the enantioselective synthesis of unnatural α-amino acids, utilizing chiral square-planar Ni(II) Schiff base complexes in combination with an A³-coupling (Mannich-type) reaction. The methodology enabled the generation of a series of α-amino acid derivatives with excellent enantiomeric excess (≥99% ee) and high chemical yields under optimized reaction conditions involving CuI/FeCl₃ catalysis in toluene under argon. The reaction demonstrated strong dependence on the nature of the amine, with cyclic secondary amines yielding superior results compared to linear or primary analogs. The obtained products were structurally confirmed via X-ray crystallography and HPLC analysis, verifying the retention of stereochemical integrity. Molecular docking studies against collagenase indicated that all synthesized compounds could interact with the enzyme via various binding domains and interaction types, particularly hydrogen bonding. Subsequent in vitro collagenase inhibition assays revealed that all compounds, except 4a, exhibited inhibitory activity, with compound 4e demonstrating the highest potency (IC₅₀ = 0.75 mM), despite not having the most favorable docking score. This highlights the importance of complementary in silico and experimental evaluations for reliable biological profiling. The presented strategy provides a versatile platform for the synthesis of structurally diverse, enantiomerically pure non-proteinogenic amino acids with promising bioactivity, offering valuable prospects for drug discovery and enzymatic inhibition studies.

Ni(II) complex of the Schiff base of the chiral auxiliary (S)-2-N-(N′-benzylprolyl)aminobenzophenone (BPB) and dehydroalanine as the initial complex in the addition reaction was investigated. The obtained four new derivatives of α-alanine were investigated as inhibitors of aldose reductase. Only one of them: (S)-2-amino-3-[(4-methylbenzyl)amino]propanoic acid showed activity. It becomes a reason for studying the patterns of biological activity of the structure of α-amino acids. The results of docking analysis indicated that (S)-2-amino-3-[(4-methylbenzyl)amino]propanoic acid demonstrated the ability to form bonds with different functional groups of the enzyme which let us assume that some amino acids of nonfunctional groups, such as Trp²⁰ of ALR2, can play a key role in inhibitor–enzyme interactions. Received: 16 August 2022 Accepted after revision: 12 September 2022 Accepted Manuscript online: 12 September 2022 Article published online: 19 October 2022 © 2022. Thieme. All rights reserved Georg Thieme Verlag KG Rüdigerstraße 14, 70469 Stuttgart, Germany

Currently non-protein amino acids and synthetic peptides are widely used as blocks in drug design. Many proteases are of great interest for pharmacology due to their key role in various pathologies. Bacterial collagenase (EC 3.4.24.3) is quite an attractive target for drug development as the inhibitors of bacterial collagenolytic protease may stop propagation of diseases caused by infections. The interaction of peptides containing unusual amino acids with Clostridium histolyticum collagenase has been evaluated by molecular docking followed by the measurement of enzyme inhibition by selected compounds. According to the docking analysis, 4 compounds were selected and synthesized for further research. Measurement of enzyme activity revealed that all tested compounds inhibited collagenase activity with IC₅₀ values ranging within 1.45–2.08 μM. The antibacterial activity of synthesized compounds against some resistant strains was characterized by MICs values ranging within 4.6–9.2 μg/ml.

Ni(II) complexes of the Schiff base of the chiral auxiliary (S)-2-N-(N′-benzylprolyl)aminobenzophenone (BPB) and α-substituted propargylglycines as the initial complexes in the Glaser reaction were investigated. Three new bis-derivatives of propargylglycine were obtained with high chemical yields. To study the patterns of biological activity of the structure of bis-derivatives of propargylglycine, mono analogs of these amino acids were obtained. Bis-derivative of propargylglycine selectively inhibited ALR2 while did not inhibit ALR1. Thus, (2S,9S)-2,9-diamino-2,9-bis(2-chlorobenzyl)deca-4,6-diynedioic selectively inhibited ALR2 with IC₅₀ = 0.335 mM, while (S)-2-(2-chlorobenzyl)-2-aminopent-4-ynoic and (2S,9S)-2,9-diamino-2,9-bis(3-fluorobenzyl)deca-4,6-diynedioic acids showed inhibitory effect on ALR1 with IC₅₀ = 0.49 mM and IC₅₀ = 0.289 mM, respectively. The results of docking analysis indicated that both amino acids demonstrated the ability to form bonds with different functional groups of the enzyme. We assume that some amino acids of nonfunctional groups, such as Trp²⁰ of ALR2, can play a key role in inhibitor–enzyme interactions. Graphical Abstract