Acta Chimica Slovenica最新文献

Silver nanoparticles synthesized using Verbascum uschakense extract at a reaction temperature of 60 °C were characterized through multiple analytical techniques. These included ultraviolet-visible absorption spectroscopy, X-ray diffraction analysis, high-resolution transmission electron microscopy, and scanning electron microscopy coupled with energy dispersive X-ray spectroscopy. Ultraviolet-visible spectral analysis revealed a surface plasmon resonance peak at 432 nanometers, indicating the successful formation of silver nanoparticles. Microscopic analyses demonstrated that the nanoparticles were predominantly spherical in shape, with particle sizes ranging between 4 and 14 nanometers. X-ray diffraction analysis confirmed that the silver nanoparticles possessed a face-centered cubic crystal structure, as evidenced by characteristic diffraction peaks at 2θ values of 38.21°, 44.46°, 64.59°, and 77.48°, corresponding to the (111), (200), (220), and (311) planes, respectively. Regarding the biological activities, the antioxidant capacity of the aqueous extract of V. uschakense was evaluated by its ability to scavenge free radicals. At a concentration of 1 milligram per milliliter, the extract demonstrated a 86.93 percent scavenging effect against the stable radical 2,2-diphenyl-1-picrylhydrazyl. In comparison, the silver nanoparticles synthesized from the plant extract exhibited a 60.04 percent scavenging effect at the same concentration. Additionally, the silver nanoparticles showed strong inhibition in the 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) radical scavenging assay, with values comparable to those obtained using the standard antioxidant TroloxThe antimicrobial properties of the biosynthesized silver nanoparticles were examined using the disc diffusion method. The nanoparticles exhibited inhibitory activity against several pathogenic microorganisms, including Staphylococcus aureus, Streptococcus mutans, Escherichia coli, Pseudomonas aeruginosa, Listeria monocytogenes, and fungal species belonging to the Candida genus. These results highlight the potential of V. uschakense-mediated silver nanoparticles as multifunctional bioactive agents with both antioxidant and antimicrobial properties. The study demonstrates that green synthesis offers a sustainable and effective approach to producing nanomaterials with potential applications in biomedical and pharmaceutical fields.

An organic-inorganic polyaniline-silica (PANI/SiO₂) nanocomposite was synthesized through a combination of electrospinning and in-situ polymerization. This synthetic strategy effectively minimized PANI aggregation during polymerization, resulting in a higher yield and improved structural uniformity. Taking advantage of these enhanced properties, the nanocomposite was electrodeposited onto a stainless-steel wire and employed as an efficient sorbent for the extraction of linear alkylbenzenes (LABs) via headspace solid-phase microextraction (HS-SPME), followed by analysis using gas chromatography coupled with flame ionization detection (GC-FID).  The structure and morphology of the synthesized sorbent were characterized using scanning electron microscopy (SEM) and Fourier-transform infrared spectroscopy (FT-IR) techniques. Response surface methodology (RSM) involving central composite design (CCD) was employed to evaluate the important experimental variables. Under the optimal conditions, linear dynamic ranges (LDRs) were in the range of 0.05-12  ng mL-1 for Φ-C11 (undecylbenzene) and Φ-C13 (tridecylbenzene), 0.02-12 ng mL-1 for Φ-C12 (dodecylbenzene) and Φ-C14 (tetradecylbenzene) with regression coefficient greater than 0.99. The limits of detection (LODs) were found to be 0.007-0.015 ng mL- 1. The developed HS-SPME-GC-FID method was successfully applied for extraction and determination of LABs in water and wastewater samples.

Modern nanofabrication technologies combined with electrochemical techniques offer benefits in terms of extremely high sensitivity, low limit of detection, minimum power requirement, simplicity, and low cost of the electrochemical sensors making them powerful for food quality evaluation. The limited number of electrochemical non-enzymatic sensing platforms for bisphenol A (BPA) successfully applied for safety assessment of foods and beverages, testifies that the food matrices present significant challenges and there is still a need to improve the analytical performances of these devices. This review systematically explores the contributions of diverse functional nanomaterials, metal-organic frameworks, ionic liquids, and molecular imprinting in improving the sensor performance. A critical discussion on the latest interesting innovations and most promising electrochemical tools for BPA analysis is presented. By addressing the electrochemical aspects and challenges in the design of BPA sensors and exploring innovative solutions, the article offers insights into future prospects and avenues, paving the way for advancements in this field.

In this study, the efficient method was introduced for the preparation of copper-periodic mesoporous organosilica nanocomposites (Cu@MOS NCs) as a high performance heterogeneous nanocatalyst. Then the nanocomposite was characterized with various methods such as X-ray diffraction (XRD), BET analysis, SEM and EDS microscopy and thermogravimetric analysis (TGA). The Cu@MOS NC as nanocatalyst was applied for one-pot three component reactions of aromatic aldehydes, dimedone, and malononitrile for the effective and green synthesis of 2-amino-4H-benzo[b]pyran derivatives in high yields, with operational simplicity, environmental friendliness, wide applicability and reusability and easy recovery of the catalyst.

A novel poly(1,4-diaminonaphthalene) was synthesized from the monomer 1,4-diaminonaphthalene at the nanoscale via an oxidative polymerization method. The reaction was conducted in an acidic (HCl) medium under an ultrasound homogenizer at 0 °C, while potassium persulfate was used as a radical initiator. This polymer has been characterized using various techniques, including FTIR, UV-Vis spectroscopy, thermogravimetric analysis (TGA), scanning electron microscopy (SEM), NMR analysis, and electron paramagnetic resonance (EPR) methods. The nanopolymers were found to be thermally stable up to 200 °C. EPR data further substantiated the presence of unpaired electrons on the nitrogen atoms within the polymer backbone.

The crystal structure of the Schiff base compound 4-hydroxy-N-[(1Z)-1-(naphthalen-2-yl)ethylidene]benzohydrazide was determined using X-ray diffraction analysis, confirming the molecular structure previously inferred from spectroscopic data. The molecule exhibits nearly planar rings with specific dihedral angles. The crystal structure features intermolecular O-H···O and N-H···O hydrogen bonds that form a two-dimensional network, significantly stabilizing the structure. Hirshfeld surface analysis identified key intermolecular interactions, with notable contributions from H···C/C···H and H···H contacts. Energy calculations highlighted the dominant role of electrostatic interactions in the overall stability of the crystal. In vitro studies identified significant anticancer effects, with IC50 values of 38 µM for MCF7 cells and 57 µM for MDA-MB-231 cells, demonstrating dose-dependent inhibition of cell viability, migration, and clonogenic growth. In silico analyses revealed a strong binding affinity to ERRγ and predicted favorable oral bioavailability. KEGG pathway enrichment analysis of the predicted targets indicated their significant involvement in cancer-related pathways. The combined structural, in vitro, and in silico analyses provide a comprehensive understanding of the compound's properties, laying a strong foundation for future preclinical and clinical studies.

A new Schiff base compound N,N'-bis(4-bromo-2-hydroxybenzylidene)ethylenediamine (H2L) was prepared by reaction of 4-bromosalicylaldehyde with ethane-1,2-diamine in methanol. Reaction of H2L with copper acetate and zinc acetate in methanol, respectively, afforded two mononuclear complexes [CuL] (1) and [ZnL(OH2)] (2). Reaction of H2L with cobalt nitrate in the presence of ammonium thiocyanate in a mixture of methanol and DMF afforded a mononuclear cobalt(III) complex [CoL(NCS)(OH2)]·DMF (3). The free Schiff base and the complexes were characterized by elemental analysis and infrared spectra, as well as single crystal X-ray determination. 1H NMR spectrum was also performed for H2L. The deprotonated form of the Schiff base coordinates to the metal atoms through all the phenolate oxygen and imino nitrogen atoms. The Cu(II) atom in complex 1 is in square planar coordination. The Zn(II) atom in complex 2 is in square pyramidal coordination. The Co(III) atom in complex 3 is in octahedral coordination. The urease inhibitory assay reveals that the copper(II) complex has the most effective activity.

A new thiazolidinone derivative, (Z)-ethyl 2-((E)-2-((E)-(4-(methylthio) benzylidene) hydrazono)-4-oxo-3-phenylthiazolidin-5-ylidene) acetate (EMBTh), was synthesized via condensation method. This study employs a multidisciplinary approach, including compound characterization, molecular properties evaluation, and biological activity analysis. Single-crystal X-ray diffraction (SC-XRD) revealed that the compound crystallizes in the monoclinic crystal system with the P21/c space group. A theoretical model of EMBTh has been developed and substantiated by comparing SC-XRD results with theoretical calculations using density functional theory (DFT), employing the B3LYP function at a 6-311++G(d,p) level of theory. The study also explores the electronic behavior of the molecule and its molecular interactions, especially highlighting van der Waals forces via analysis of the molecular frontier orbitals and Hirshfeld surface. The results underscore the stability of the molecule and the significant contribution of hydrogen bonds to the crystal packing. Moreover, we conducted a molecular docking study to evaluate the anti-eczema activity of the EMBTh compound. The results revealed a good affinity in inhibiting the receptor (IL-4Rα), pinpointing the therapeutic potential of EMBT against the target protein of atopic eczema.

4-Amino-5-substituted-4H-1,2,4-triazole-3-thiols are versatile synthons for constructing of various biologically active heterocycles. This is provided by the close proximity of the amino and mercapto groups, which serve as readily accessible nucleophilic centers for the preparation of N-bridged heterosystems. One of the possible and convenient directions of using 4-amino-4H-1,2,4-triazole-3-thiols in heterocyclic synthesis based on their utilization in reaction with various carboxylic acids in the presence of dehydrating reagents, most often phosphorus oxochloride. Synthesized as follows [1,2,4]triazolo[3,4-b][3,4-b]thiadiazole derivatives may differ by various substituents in positions 3 and 6 such as alkyl-, aryl-, aryl(oxy)alkyl-, heteryl- etc. In this review, we presented the synthetic strategies and subsequent chemical transformations of the resulting triazolo[3,4-b]thiadiazoles, providing certain important class of functionalized compounds.

Herein, a series of new 2-amino-4,6-dihydropyrano[3,2-c]isochromene-3-carbonitrile derivatives (4a-o) have been synthesized by one-pot three component reaction of 4-hydroxyisocoumarin, various aromatic aldehydes, and malononitrile in the presence of triethylamine in EtOH at reflux conditions. All the newly synthesized compounds were characterized using standard spectroscopic techniques (FT-IR, 1H and 13C NMR) and elemental analysis. The cytotoxicity of the synthesized compounds was determined by MTT assay on one normal (3T3) and two cancer cell lines (A549 and MCF-7). It was revealed that some of these compounds (4b, 4f, and 4j) are toxic especially for MCF-7 cell line and can be considered as lead compounds for further investigation. Howevere, the other compounds had low cytotoxicity and can be suitable candidates for other pharmacological effects such as antibacterial, antifungal, antiviral, etc.