Research on Chemical Intermediates最新文献

A straightforward ultrasound-assisted green multicomponent strategy was developed for synthesising benzo[h]pyrimido[4,5-b]quinoline-8,10(7H,9H)-dione derivatives. The protocol involves the condensation of 1-aminonaphthalene, barbituric acid, and various aromatic, aliphatic, and heterocyclic aldehydes under ultrasonic irradiation in aqueous ethanol as a benign solvent system. Ultrasound-promoted acoustic cavitation affords excellent yields, shorter reaction times, and high selectivity under mild, environmentally friendly conditions, in line with green chemistry principles. The synthesised derivatives were fully characterised by spectroscopic techniques. ADMET predictions indicated favourable pharmacokinetic properties. Molecular docking revealed strong binding affinities, particularly for compounds 4(e–o), with docking scores ranging from –7.05 to –9.80 kcal/mol against the progesterone receptor (PDB ID: 4OAR). Density functional theory (DFT) studies, including HOMO–LUMO analysis, provided valuable insights into the electronic structures and reactivity patterns of the molecules. Overall, this work demonstrates ultrasound-assisted multicomponent synthesis as a sustainable strategy for constructing bioactive heterocycles and suggests that the obtained derivatives hold potential for further development as anti-breast cancer agents.

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A series of hierarchical nanosheet-structured ZSM-5 zeolites were successfully synthesized via a dual-template synthesis strategy. The impacts of the material ratio in the gel include meso-/microporogen and Si/Al molar ratio, as well as the type of microporogen on the morphology of the hierarchical structure of zeolites, pore architecture, and acidic properties were systematic explored. Moreover, the relationship between the morphological changes and the arrangement of the template within the uncalcined zeolite was unveiled. The results indicated that the molar ratio of C_18-6-6Br (mesoporogen)/TPAOH exerted a remarkable influence on the morphology of zeolites. With the increase in the proportion of the C_18-6-6Br, the morphology of the zeolites shifted rapidly from massive to lamellar. Concomitantly, N₂ adsorption–desorption experiments show that both the specific surface area (ranging from 380 to 570 m²/g) and the external specific surface area (ranging from 188 to 382 m²/g) increased significantly. While the Si/Al ratio variations adjusted acid strength and quantity through crystallinity interplay, the type of microporogen influenced crystallization via electrostatic interactions and steric effects. Light olefins were produced by the catalytic cracking of waste cooking oil model compound in laboratory-scale fixed-bed reactors to evaluate the catalytic performance of these zeolites. The maximum light olefin yield (38.8%) could be obtained owing to the suitable acid amount and relatively large specific surface area of zeolite (500 m²/g). While meeting the yield requirements, it also achieved a relatively low coke deposition (23.54% coke content) through excellent diffusion performance.

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Having already been extensively studied due to containing two of the three most common heteroatoms, thiocarbohydrazone derivatives represent an intriguing class of compounds for many scientists. They have shown great biological activity as antioxidative, antimicrobial, and anticancer agents. In this paper, previous studies have been continued—from the series of monothiocarbohydrazones, asymmetrical bisubstituted derivatives were synthesized. Eighteen new bisthiocarbohydrazones were obtained and characterized. Purity and composition of synthesized compounds were determined with NMR (¹H, ¹³C) and FT-IR spectroscopy and elemental analysis. Six derivatives were successfully isolated in the form of single crystals, and X-ray analysis was applied. Intermolecular interactions were studied using multiple linear correlations based on LSER and LFER principles. In order to examine the antioxidative potential of new bisthiocarbohydrazones, the DPPH assay was used, and all compounds showed good activity. Derivatives with hydroxyl and methoxy groups, as well as those with a fluorine atom, proved to be the best antioxidant agents in this series of thiocarbohydrazones.

A novel dicationic Brønsted acidic ionic liquid (DBAIL) was synthesized via an acid–base reaction between 1-((3-dimethylammonium)propyl)pyridinium chloride and sulfuric acid. The obtained ionic liquid was thoroughly characterized by Fourier transform infrared (FT-IR) spectroscopy, proton nuclear magnetic resonance (¹H NMR) spectroscopy, carbon-13 nuclear magnetic resonance (¹³C NMR) spectroscopy, thermogravimetric analysis (TGA)/differential thermogravimetric analysis (DTG), mass spectrometry (MS), and the Hammett acidity function, thereby confirming its structural features and ionic properties. The DBAIL catalyzed the reaction of aldehydes, dimedone, and ammonium chloride at 110 (^{circ })C with 20 mol % of the DBAIL under solvent-free conditions, affording a series of 1,8-dioxodecahydroacridine derivatives with yields of up to 95 %. This synthetic method offers several advantages, including short reaction times, high yields along with low catalyst loading in neat conditions, and a simple work-up. Furthermore, the antibacterial activity of DBAIL was assessed against a panel of pathogenic microorganisms, revealing strong antimicrobial effects against both Gram-positive and Gram-negative bacteria, while no activity was observed against Candida albicans. These results underscore the potential of the DBAIL for applications in both synthetic chemistry and biomedicine. Finally, the in vitro cytotoxicity of the DBAIL was evaluated by MTT assay.

Lignin quantum carbon dots (CQDs) were prepared using basic lignin as the carbon source. They were loaded onto Z-type ZnIn₂S₄/WO₃ heterojunction semiconductor materials by a one-step hydrothermal method to construct a ternary composite photocatalyst. Taking the photocatalytic water hydrogen evolution reaction performance as an indicator, it was found that the 33% CQDs/ZnIn₂S₄/WO₃ composite photocatalyst exhibited the highest hydrogen evolution reaction rate of 15.355 mmol·h⁻¹·g⁻¹, which was twice as high as that of ZnIn₂S₄/WO₃ (7.522 mmol·h⁻¹·g⁻¹). This study successfully constructed CQDs/ZnIn₂S₄/WO₃ tenary heterojunction photocatalyst with excellent and stable hydrogen production performance, which fully demonstrated the feasibility of loading lignin-based CQDs to enhance the photocatalytic performance of ZnIn₂S₄ for high-value utilization of lignin.

A novel drug delivery system based on amorphous zeolite derived from kanemite for doxorubicin (Dox) has been constructed. Structural analysis indicated that the initial Na-Ka was an orthorhombic structure with lattice parameters of a = 7.267(9)Å, b = 21.03(3)Å, and c = 4.878(8)Å. After protonation of Na-Ka by HCl solution, the resulting H-Ka was an zeolite with orthorhombic structure, and its lattice parameters are a = 7.45(2)Å, b = 11.85(5)Å, and c = 4.905(9)Å. Then the H-Ka was reacted with tetra-n-butyl ammonium hydroxide (TBAOH) solution, yielding Ka-TBA colloid suspension, and the Ka-TBA sediment exhibited amorphous state. While the Ka-TBA colloid suspension was reacted with doxorubicin (Dox) hydrochloride solution by ion exchange, the yielded Ka-Dox was amorphous. Composition analyses revealed that the chemical formula of Na-Ka, H-Ka, and Ka-Dox was estimated to be NaHSi₂O₄(OH)₂·2.0H₂O, H₂Si₂O₅·0.72H₂O, and H_1.82(C₂₇H₃₀NO₁₁)_0.18·Si₂O₄(OH)₂·1.31H₂O, respectively. The loading capacity of Ka-Dox for Dox was about 35.24%. Drug release suggested that the Ka-Dox exhibited extremely slow and sustained release of drug in phosphate buffer solution (PBS, pH = 7.4), and the drug release percentages were 2.42%, 2.84%, 3.12%, and 3.40% after 24 h, 48 h, 72 h, and 96 h, respectively. This extremely slow and sustained release of drug may be potential application in the medical field, such as maintaining stable blood drug concentrations over prolonged periods, improving the compliance and safety of drug treatment, and reducing the toxic side effects.

This study highlights the design of a novel organo-nanocatalyst by grafting of thiourea onto dendritic fibrous nanosilica (DFNS). The resulting catalyst, named KCC-1-nPr-thiourea, was characterized using advanced techniques, such as FE-SEM, TEM, FT-IR, EDAX, mapping analysis. Also, pore size, pore volume and surface area of KCC-1-nPr-thiourea was determined by BET-BJH adsorption/desorption method which were 14.44 nm, 0.36 cm³/g and 100 m²/g, respectively. The analysis revealed that the catalyst exhibits uniform spherical morphologies with a fibrous dendritic structure. The fabricated nanocatalyst (KCC-1-nPr-thiourea) demonstrates outstanding performance due to its unique dendritic structure, which greatly enhances the accessibility of its active sites. KCC-1-nPr-thiourea as an advanced heterogeneous nanocatalyst, enhance the efficiency of 1,8-dioxo decahydroacridine synthesis through a one-pot, four-component reaction involving aromatic aldehydes, dimedone, and ammonium acetate, under solvent-free conditions. Its specialized structure optimizes the dispersion and adsorption of reactants and products within its pores and channels, contributing to its effectiveness in catalysis. This innovative approach dramatically reduces reaction times to just 10–20 min, yielding impressive product outputs of 93–98%, outperforming previously documented methods. With its multifunctional nature and environmentally friendly design, this organo-nanocatalyst offers a highly efficient and sustainable platform for producing diverse organic compounds. The porosity, high surface area and stability of silica nanoparticles as a support enhances the catalytic activity, recoverability and reusability of thiourea functional group.

The environmental pollution caused by organic dye wastewater presents a significant threat to human health. Photocatalysis has emerged as a promising approach for addressing wastewater contamination. In this study, a novel synthesis strategy was developed using the MOF-5 template method. By precisely regulating the amount of Bi³⁺ ions introduced into the MOF-5 precursor and employing controlled calcination, Bi-doped ZnO nanomaterials were successfully synthesized. XRD, SEM, TEM, and XPS analyses demonstrated that a 4% Bi doping level resulted in uniform incorporation of Bi into the ZnO crystal lattice, inducing local coordination modifications. EPR results indicated that the surface oxygen vacancy density of Bi–ZnO (4%) was higher than that of pure ZnO, which contributed to enhanced photocatalytic performance. UV degradation experiments revealed that at a Bi content of 4%, the degradation efficiency of methyl orange reached a maximum of 92%, significantly surpassing the 57.5% efficiency observed for pristine ZnO. Furthermore, cycling experiments confirmed the excellent stability of the catalyst. Reaction mechanism investigations indicated that photogenerated holes (h⁺) played a dominant role in the degradation of methyl orange by Bi–ZnO. Density functional theory (DFT) calculations indicate that bismuth doping renders the material metallic, thereby facilitating the efficient separation of photogenerated charge carriers. Under light irradiation, these doping-induced holes facilitated the formation of a space charge layer, thus facilitating the effective separation of photoinduced electron–hole pairs.

This study investigated the use of commercial chitosan as a simple, eco-friendly, and efficient organocatalyst for the synthesis of xanthene and tetraketone derivatives via a cascade reaction. The reaction between various salicylaldehydes and dimedone (1:2 molar ratio), conducted in water at 75 °C, and catalyzed by chitosan, produced xanthene derivatives (3a–g) in good to excellent isolated yields (73–93%) within short reaction times (10–60 min). When benzaldehyde was employed as the aldehyde component, tetraketone derivatives (5a–g) were formed instead of xanthene derivatives. A series of substituted benzaldehydes were also investigated, efficiently affording the corresponding Tetraketone derivatives in high yields (82–94%) and short reaction times (10–20 min). The reusability of chitosan was confirmed, with no significant decrease in catalytic activity or structural integrity after six consecutive cycles. The synthesized compounds were evaluated for their cytotoxic activity against K-562, A-549, and HCT-116 tumor cell lines, as well as the non-tumor cells MRC-5. Xanthene derivatives demonstrated superior activity, particularly compound 3f, which exhibited low IC₅₀ value for HCT-116 (5.54 µM) and SI of 0.54 (SI = IC_{50 (MRC-5)}/IC_{50 (HCT-116)}). These findings indicate the potential of these molecules as anticancer agents, while also highlighting the need for further structural optimization to enhance selectivity, especially against colon cancer cells.

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A microwave-assisted method was developed for rapid synthesis of histidine-functionalized copper nanoclusters (His@CuNCs) as fluorescent probes for vitamin B12 (VB12) detection. This method uses histidine as a stabilizer and ascorbic acid as a reducing agent, enabling single-step green synthesis within 1 min, much faster than traditional methods. The nanomaterial exhibited intense blue–green fluorescence (λem = 466 nm) with quantum yield of 10.38%. Moreover, the His@CuNCs showed exceptional environmental stability, maintaining their optical properties under varying ionic strengths, pH conditions, and prolonged UV exposure. Upon VB12 introduction, specific electron transfer from VB12 to His@CuNCs caused fluorescence quenching via static quenching and IFE mechanisms. The probe demonstrated a linear response from 0.5 to 270 μM with 0.033 μM LOD, outperforming most of existing nanocluster-based sensors. The platform demonstrated practical utility of determination of vitamin B12 in vitamin drink and bovine serum samples, and sensing temperature.