Russian Journal of Bioorganic Chemistry最新文献

Objective: This article focuses on the design, synthesis, and characterization of C-19 acylamino-functionalized isosteviol derivatives, and their evaluation for LSD1 inhibitory activity as well as molecular docking studies. Methods: The novel C-19 acylamino-functionalized isosteviol derivatives were designed based on the principle of drug combination, and were subsequently synthesized via acetylation with acyl chlorides and condensation with amines. The LSD1 inhibitory activity of the synthesized compounds was evaluated using the LSD1 small molecule inhibitor screening platform. Molecular docking studies were performed using MOE (Version 2019). Results and Discussion: The synthesized C-19 acylamino-functionalized isosteviol derivatives were characterized by IR, NMR, and HR-MS spectra. The results of the anti-LSD1 activity assays showed that compounds with cyclic substituents generally exhibited excellent inhibitory activity. In particular, compound IIIl exhibited the best LSD1 inhibitory effect, with an IC₅₀ value of 8.523 ± 0.882 μM. Further molecular docking studies revealed that the 16-carbonyl group of compound IIIl formed a hydrogen bond with the Ser289 residue, and its aromatic ring formed a π-H interaction with the Met332 residue. Additionally, the top-ranked docking pose of compound IIIl showed a strong binding affinity to the LSD1 protein, with a docking score of –5.273.Conclusions: This study lays the groundwork for the development and structural modification of new isosteviol-based drugs.

Objective: Benzothiazole derivatives linked to coumarin exhibit a broad spectrum of biological activities. Based on this rationale, we synthesized several compounds containing triheterocyclic structures, which are connected via a methine (–CH) group and also feature a biologically relevant thioether bond (–C–S). Methods: We used L-proline as a catalyst in a multicomponent one-pot synthesis. The structures of the synthesized compounds were confirmed by various instrumental techniques, including IR, ¹H, ¹³C NMR, and mass spectrometry. Results and Discussion: The obtained benzothiazole thioether derivatives were screened for antibacterial activity against Eю coli and Sю aureus using the zone of inhibition method. Compounds IVa and IVc exhibited promising antibacterial activity. Conclusions: The synthesized benzothiazole thioether derivatives show potential antibacterial activity, particularly compounds IVa and IVc.

Objective: The tetrapeptide Ac–Trp–Pro–Arg–Gly–NH₂, a C-terminal fragment of arginine vasopressin (AVP), is of high interest as a potential pharmaceutical agent for developing new antidepressant and anxiolytic drugs. In this work we aimed to improve synthetic approach for obtaining the compound and perform its toxicological evaluation. Methods: Ac–Trp–Pro–Arg–Gly–NH₂ was synthesized by classical methods of peptide chemistry using a convergent approach to chain assembly and activated ester and carbodiimide methods as condensation methods. The cytotoxicity of the synthesized peptide against human fibroblast cells was assessed by the MTT assay. Acute toxicity was studied on ICR mice (n = 16 in experimental group; n = 16 in control group) with intranasal administration of the tetrapeptide. The toxicity of Ac–Trp–Pro–Arg–Gly–NH₂ was assessed by monitoring changes in the body weight of rodents and visual changed in their internal organs. Results and Discussion: This study shows that the new “block” scheme allows to produce the tetrapeptide in higher yields (2–3 times) than was shown previously. Ac–Trp–Pro–Arg–Gly–NH₂ demonstrated no cytotoxicity on fibroblasts in the range of expected therapeutic doses (IC₅₀ >1000 μM) and did not exhibit any clearly expressed pathological effect on the internal organs of experimental mice under conditions of the experiment. Conclusions: The low toxic effects of tryptophan-containing AVP analog demonstrated in this work makes the tetrapeptide a promising substance for further investigations of biological activity, toxicity and mechanisms of action with the aim of creating new, safer and more effective anxiolytics and antidepressants based on the compound.

Objective: Synthesis of a new series of fluorescent dyes based on Kaede chromophore moiety for selective mitochondria and nucleus staining. Methods: [3+2]-cycloaddition of carboxyimidate to aromatic imines. Reaction of arylidene imidazolone with BBr₃ followed by treatment with aqueous HF was used in synthesis of difluoroboranyl compound. Condensation of corresponding aromatic aldehydes with active methyl group of arylidene-imidazolone was used for Kaede chromophore analogues synthesis. UV-VIS spectroscopy and fluorimetry was used to study optical properties of new chromophores. The widefield fluorescence microscopy was used for imaging of cellular structures. Results and Discussion: We discovered that 5-((Z)-4-(dimethylamino)-3-hydroxybenzylidene)-3-methyl-2-((E)-2-(pyridin-4-yl)vinyl)-3,5-dihydro-4H-imidazol-4-one can act as a fluorogen for mitochondria and nucleus. Conclusions: We created a series of three new arylidene imidazolone fluorogens and showed that compound can be used as a dye for mitochondria and nucleus in widefield fluorescence microscopy.

Objective: One of the most promising approaches to addressing the problem of bacterial resistance is the development of antibacterial drugs with a novel mechanism of action. Oxazolidinones are a class of synthetic antibacterial drugs with high activity against a wide range of Gram-positive bacteria, including resistant strains. A library of 11 pyridoxine derivatives containing 1,3-oxazolidin-2-one fragments at the second, fifth, and sixth positions was synthesized. Methods: The structures of the synthesized compounds were confirmed by ¹H, ¹³C NMR spectroscopy and mass spectrometry. The target oxazolidinone derivatives were obtained using organic synthesis methods. Numerous biological experiments were performed to evaluate the antibacterial activity and toxicity of the synthesized compounds. Results and Discussion: The antimicrobial activity testing on 6 reference strains and 6 clinical isolates of Gram-positive bacteria, as well as in vitro toxicity against a panel of normal human cells (HSF, MSC, and HEK-293), revealed a highly active and low-toxicity lead compound containing a 1,3-oxazolidin-2-one fragment at the fifth position of pyridoxine. Subsequent studies on bacterial biofilms of S. aureus and E. faecium demonstrated comparable and, in some cases, superior efficacy to linezolid. The lead compound, unlike linezolid, did not exhibit a mutagenic effect in the Ames test and also showed high safety upon intragastric administration to mice (LD₅₀ >2000 mg/kg). Conclusions: The results indicate that pyridoxine derivatives containing 1,3-oxazolidin-2-one fragments are of interest for antibacterial drug development.

Objectives: Isatin and 2-oxoindole are valuable synthetic building blocks with diverse biological properties, including antifungal, antibacterial, antitumor, and anticancer activities. Due to the growing threat of pathogen resistance to current antimicrobial, nematicidal, and antienzymatic agents, our research group focuses on discovering new compounds with promising biological potential. Methods: N-1 alkylated isatin was synthesized in the presence of K₂CO₃. The N-1 alkylated isatin was then reacted with 2-oxoindole in the presence of the acid-base catalyst ZrCl₄ to afford N-1 alkylated isoindigo derivatives, which were characterized using ¹H, ¹³C NMR, and FT-IR spectroscopy. The synthesized derivatives were evaluated for their antimicrobial activity against Dickeya sp., Streptomyces sp., Fusarium oxysporum, and Rhizoctonia solani, their nematicidal efficacy against the plant pathogen Meloidogyne incognita, and their inhibitory potential against acetylcholinesterase. Results and Discussion: Among all synthesized derivatives, the isoindigo compound VIj (3-(1-decyl-2-oxoindolin-3-ylidene)indolin-2-one) exhibited the highest biological activity. It demonstrated significant antibacterial activity, with MIC values of 39 and 36 μg/mL against Dickeya sp. and Streptomyces sp., respectively. Similarly, the compound showed remarkable antifungal activity, with MFC values of 278 and 292 μg/mL against Fusarium oxysporum and Rhizoctonia solani, respectively. Regarding its nematicidal activity, VIj displayed potent inhibition against Meloidogyne incognita. The LC₅₀ and LC₉₅ values for egg hatch inhibition were determined as 0.193 and 1.462 mg/mL, respectively, while for juvenile mortality, the LC₅₀ and LC₉₅ values were 0.152 and 0.995 mg/mL, respectively. Additionally, the inhibitory activity of VIj against the acetylcholinesterase enzyme of M. incognita was evaluated, revealing an IC₅₀ value of 210.4 μg/mL. These findings highlight VIj as a novel scaffold with significant antimicrobial, antifungal, and nematicidal properties. Conclusions: Its promising biological activities make it a valuable candidate for the agrochemical sector, where such compounds are in high demand for potential agricultural applications.

Objective: The transcriptional coactivator CREBBP (cyclic AMP response element binding protein-binding protein), neuron-specific transcriptional regulator HTT (huntingtin) and histone-lysine methyltransferase KMT2D (lysine methyltransferase 2D) cooperatively participate in post-translational modification of histones and regulation of differential gene expression. The mechanism of protein-protein interactions has been poorly studied. Methods: Computer analysis of the primary structure of proteins using the principal components method revealed the presence of the highest possible correlation between the main components of amino acid sequences in the CREBBP–HTT and CREBBP–KMT2D pairs with glutamine. Results and Discussion: The trajectory of the first principal component of CREBBP practically coincides with the graph of the positional frequency of glutamine along the protein molecule. It is shown that in the secondary structure of CREBBP a significant share is occupied by E-strand (extended strand) elements with an open conformation of the peptide chain. Polyglutamine tracts localized at the C-terminus of CREBBP, N-terminus of HTT, N-, C-termini and in the center of KMT2D also have an open conformation facilitating the formation of intermolecular hydrogen bonds. Conclusions: It is assumed that the polyglutamine tracts of the C-terminus of CREBBP and the N-terminus of HTT are directly involved in the protein-protein contact of CREBBP–HTT. A similar connection between the polyglutamine tracts of the C-terminus of CREBBP and the central region of KMT2D fixes the physical interaction in this pair of proteins. The identified features of the studied proteins can be used to design new pharmacological drugs using physicochemical methods.

Objective: The development of effective antiviral agents targeting whitefly-transmitted begomoviruses using a one-pot multicomponent reaction (MCR) approach. Methods: The synthesis was performed via a one-pot multicomponent reaction of aryl aldehydes, thiourea, and ethyl cyanoacetate in an ethanolic solution of potassium carbonate. The compounds were characterized using ¹H, ¹³C NMR, FT-IR spectroscopy, and mass spectrometry. In vivo antiviral studies of the resulting compounds were conducted against whitefly-transmitted begomovirus using simultaneous, protective, and curative approaches. Results and Discussion: The results revealed that the synthesized derivative 6-(4-chlorophenyl)-4-oxo-2-thioxo-1,2,3,4-tetrahydropyrimidine-5-carbonitrile IVa exhibited the best antiviral activity at 125 µg/mL in the protective approach. Conclusions: The synthesized compound IVa shows promising antiviral activity and could be considered for further development.

Objective: Methods for obtaining new derivatives of N⁴-dodecylamino-2′-deoxycytidine and cytidine have been developed with the aim to prepare convenient synthons for the introduction of tags (above all, fluorescent dyes) into biopolymers and cells for further study of their cellular localization. Methods: The new derivatives contain 5-ethynyl, 5-(prop-2-in-1-yl)oxymethyl, or 5′-azido groups necessary for the introduction of dyes in vitro using click chemistry methods. Results and Discussion: The obtained compounds, like N⁴-dodecylamino-2′-deoxycytidine, showed significant antibacterial activity against Gram-positive bacteria. Conclusions: The new nucleosides can be used for visualizing their subcellular localization, which may help in determining the potential mechanism of action of antibacterial agents of this type.

Objective: Hemolysin II (HlyII) is a key pathogenic factor of Bacillus cereus. This pore-forming toxin has a β-barrel spatial structure and possesses a C-terminal extension of 94 amino acid residues, designated the C-terminal domain of HlyII (HlyIICTD). In this work, site-directed mutagenesis was performed on amino acid residues located on the surface of the HlyIICTD protein globule. It was demonstrated that the C-terminal domain can exist simultaneously in several structural isoforms. The transition of the 3D HlyIICTD structure into a stable form within the water-soluble full-length toxin monomer was observed. Methods: Recombinant proteins and their mutant forms were obtained using the Escherichia coli BL21(DE3) producing strain. Their interaction with monoclonal antibodies HlyIIC-16 and HlyIIC-23 was studied by ELISA. To define the epitopes of HlyIIC-16 and HlyIIC-23, phage display, site-directed mutagenesis, gene cloning of individual parts of the HlyIICTD molecule, and 3D modeling of HlyIICTD fused to SlyD using the AlphaFold program were employed. Results and Discussion: Monoclonal antibodies against HlyIICTD interacted more effectively with intact HlyIICTD than with the full-size toxin or the chimeric protein HlyIICTD fused with SlyD. The HlyIIC-16 and HlyIIC-23 antibodies effectively inhibited each other's interaction with immobilized HlyIICTD in ELISA, indicating partial or complete overlap of their epitopes. The HlyIIC-16 and HlyIIC-23 epitopes are localized within the Gly341–Gly364 region of the HlyII protein. Conclusions: The multiplicity of structural isoforms of the C-terminal domain is disrupted when it is incorporated into the water-soluble full-size toxin monomer or into a recombinant protein containing the chaperone SlyD.