Preparation, characterization, and application of curcumin Schiff base complexes.

Condensation of curcumin with furfuryl amine led to the synthesis of H₂L Schiff base in a 1:1 Molar ratio. Subsequently, complexes of this Schiff base with several transition metal ions were prepared also in one-to-one molar ratio. Multiple characterization techniques were employed to identify the structure of all compounds. Infrared, UV, proton magnetic resonance spectroscopic tests, elemental analysis, mass spectrometry, thermal analysis, molar conductivity, and density function theory (DFT) calculations were utilized to gain a comprehensive understanding of their structures. Except for the nickel (II) complex, which exhibits non-electrolyte behavior, all complexes were found to exhibit electrolytic behavior based on molar conductivity studies. Additionally, thermogravimetric analysis was employed to learn more about the complexes' thermal breakdown and the Schiff base ligand's thermal behavior. From DFT studies, some parameters were obtained as bond angles and lengths, chemical hardness, softness, energy levels of highest occupied molecular orbital and lowest unoccupied molecular orbital, electrophilic index, dipole moment, electronegativity, and other variables. Against one or more bacterial species, it was discovered that the antibacterial activity of the metal complexes was superior to that of the free Schiff base. Furthermore, the complexes exhibited notable antioxidant activity according to the results obtained using DPPH scavenging. Overall, a detailed characterization of the synthesized compounds was performed, revealing their structural features, functional properties, and potential applications. Lastly, research on molecular docking was investigated toward all compounds against 3C1L antioxidant protein receptor.

In vitro, antituberculosis, anti-inflammatory, antibacterial, and antifungal activities of transition metal (II) complexes having thiosemicarbazone ligands were carried out. Further, molecular docking, DFT, MESP, and ADMET studies were proposed to give new insights into the research and to support in vitro results.

Infectious diseases have held a prominent place in the history of humanity, shaping societies, influencing medical advances, and affecting the lives of individuals on a global scale and are caused by a variety of pathogens that lead to a wide range of illnesses. Among this diverse group of ailments, tuberculosis (TB), inflammatory conditions, and various bacterial and fungal diseases stand out as major challenges that have long plagued humanity. Thus, the aim of this research is delve a significant combatting agent against TB, inflammation, bacterial and fungal deformities. To explore the above facts and to examine the therapeutic potential, the previously synthesized thiosemicarbazones (1–2) and their Co (II), Ni (II), Cu (II), Zn (II) complexes (3–10) of benzaldehydes and 4-(4-ethylphenyl)-3-thiosemicarbazide were proposed for in vitro investigation by microplate Alamar Blue, bovine serum albumin, and serial dilution methods. The compound (10) demonstrates almost double effectiveness in controlling TB dysfunction (minimum inhibitory concentration [MIC] value 0.006 ± 0.001 μmol/mL), surpassing streptomycin, whereas (6) and (9) have comparable TB inhibition efficacy to streptomycin. The compound (10) also has the highest potency for inflammation (6.75 ± 0.09 μM), bacterial (0.0066 μmol/mL), and fungal (0.0066 μmol/mL) ailments among the tested compounds with comparable inhibition abilities to their respective standard drugs. Moreover, molecular docking (targeting the PDB ID 6H53 and 1CX2 proteins), density functional theory (DFT), molecular electrostatic potential (MESP), and absorption, distribution, metabolism, excretion, and toxicity (ADMET) evaluations were performed against the highly efficient ligand (2) and its complexes (7–10) to validate the in vitro results. In this endeavor, our aim is to actively participate in the continuous initiatives aimed at fighting infectious diseases and enhancing global health and overall well-being.

Biochar was modified with ternary metal oxides ZnO, Sm₂O₃, and MgO via the one-step pyrolysis method. The removal efficiency of 2b-ZnSm/Mg-biochar was 99.46% for 410-mg g⁻¹ RhB solution. Second-order and Langmuir models well described the adsorption kinetics of ZnSm/Mg-biochar.

To boost the adsorption-photocatalytic performances of biochar in wastewater treatment, biochar was modified with ternary metal oxides ZnO, Sm₂O₃, and MgO (ZnSm/Mg-biochar) via the one-step pyrolysis method. The optimal 2b-ZnSm/Mg-biochar with a Zn/Sm molar ratio of 1:1 exhibited the better removal activity of RhB in comparison with biochar, 2-Mg/biochar, and b-ZnSm/biochar. The removal efficiency and adsorption capacity of 2b-ZnSm/Mg-biochar was 99.46% and 979.22 mg g⁻¹ for RhB solution of 410 mg g⁻¹, respectively. The adsorption kinetics and isotherms of ZnSm/Mg-biochar composites were as described by second-order and Langmuir models, respectively. The abundant vacant sites at the junction interface of ZnO, Sm₂O₃, MgO, and biochar were favorable for the adsorption and photon capturing, achieving the efficient photo-conversion of RhB under the stimulated solar-light irradiation.

Boehmite (AlOOH) is a stable phases of alumina, which was prepared by addition NaOH solutions to Al(NO₃)₃.9H₂O solution, and further, its surface was modified with (3-aminopropyl)triethoxysilane. Then, di(pyridin-2-yl)methanone was immobilized on the surface of modified AlOOH as a heterogeneous Schiff-base ligand. In the final step, a palladium complex was stabilized on its surface (Pd-di(PM)@AlOOH) as a reusable, practical, and novel catalyst in the C-C coupling of Suzuki reaction. This catalyst was characterized by TGA, FT-IR, TEM, SEM, EDS, WDX, and ICP techniques. Due to recoverability and heterogeneous nature of this catalyst, it can be reused for several runs without palladium leaching or any reactivation.

Boehmite is one of the stable phases of alumina that is easily available, and it also has a variety of applications. Therefore in this work, for preparation of AlOOH, Sodium hydroxide (NaOH) solutions was added to aluminum nitrate nonahydrate (Al(NO₃)₃.9H₂O) solution. Then, the surface of AlOOH was modified with (3-aminopropyl)triethoxysilane (APTES), due to high condensation of hydroxyl groups on its surface. Then, di(pyridin-2-yl)methanone (di(PM)) was immobilized on the surface of modified AlOOH toward synthesis of immobilized Schiff-base on AlOOH (di(PM)@AlOOH) as a heterogeneous Schiff-base ligand. Finally, a palladium complex was immobilized on its surface (Pd-di(PM)@AlOOH) as a reusable, practical, and novel nanocatalyst. Pd-di(PM)@AlOOH was characterized by thermogravimetric analysis (TGA) analysis, Fourier-transform infrared spectroscopy (FT-IR), transmission electron microscopy (TEM), scanning electron microscope (SEM) imaging, energy-dispersive X-ray spectroscopy (EDS) analysis, wavelength-dispersive X-ray spectroscopy (WDX) analysis, and inductively coupled plasma (ICP) analysis. After the characterization of Pd-di(PM)@AlOOH, its performance was used as a highly practical, stable, retrievable, and hybrid organic–inorganic catalyst in the C-C coupling of the Suzuki reaction. The hot filtration study of Pd-di(PM)@AlOOH revealed that it acts heterogeneously in the Suzuki reaction. We found that this catalyst can be recycled for five runs without palladium leaching, as studied by hot filtration test and ICP analysis.

Yolk–shell Ni–Co bimetallic nitride/oxide (NiCoNO) heterostructures, derived from NiCo-glycerate solid spheres, demonstrates excellent electrochemical performance as supercapacitor electrode.

Hierarchical core–shell structure is benefit for the fast diffusion and bulk storage of electron/ion while metal nitrides (MN) exhibit metal-like behavior with excellent conductivity. Herein, nickel cobalt glycerate solid spheres (NiCo-G) and nickel cobalt glycerate yolk–shell structure (NiCo-GYS) were successfully synthesized via solvothermal reactions, accompanied by annealing using urea as a cheap and convenient nitrogen source to obtain metal nitride/bimetallic oxide core–shell heterostructure (NiCoNO). Excellent specific capacitance of 1878 F g⁻¹ at 1 A g⁻¹ is displayed by the prepared NiCoNO. Amazingly, the distinct core–shell construction guarantees high stability during the charge/discharge operation. NiCoNO maintains an 83.9% specific capacitance after 5000 cycles at 10 A g⁻¹. Furthermore, the all-solid-state hybrid supercapacitor was assembled using NiCoNO cathode and active carbon (AC) anode components. The device has an excellent capacitive retention rate of 81.1% after 5000 cycles at 10 A g⁻¹ and a good energy density of 64.2 Wh kg⁻¹ at a power density of 900 Wh kg⁻¹. A light-emitting diode (LED) bulb can be lighted for 3 min, indicating the promising practical application prospect of the supercapacitor.

In this article, a strategy for the preparation of the Pd@CN@TiO₂ composite photocatalyst with the co-regulation of oxygen vacancies and heterojunction structure were developed. The catalyst exhibited excellent catalytic activity in the photocatalytic Suzuki coupling reaction (30 W LED: 455 nm, r.t, 3 h, Yield = 99%).

This paper reports a concise strategy for the controlled preparation of Pd@g-C₃N₄/TiO₂ photocatalysts rich in oxygen vacancies. The scheme forms black TiO₂ with oxygen vacancies on a carbon nitride material by in-situ growth and heat treatment, and then utilizes solvothermal reduction to load metallic palladium into the material. The composites were structurally analyzed using Fourier transform infrared (FT-IR), X-ray photoelectron spectroscopy (XPS), X-ray diffraction analysis (XRD), transmission electron microscopy (TEM), electron paramagnetic resonance (EPR), scanning electron microscopy (SEM), elemental mapping, diffuse reflectance spectroscopy (DRS), and inductively coupled plasma (ICP) analysis. The results show that the oxygen vacancies in the black TiO₂ materials prepared by the method reported in this paper can effectively improve the separation efficiency of the photogenerated electron–hole pairs and prolong the lifetime of the charge carriers by inhibiting charge recombination. In addition, the heterojunction structure formed between TiO₂ and g-C₃N₄ materials also enhances the photocatalytic performance of the materials to some extent. After a simple optimization of the conditions, the Pd@g-C₃N₄/TiO₂ photocatalyst could promote the Suzuki–Miyaura CC coupling reactions under mild conditions (room temperature, 30 W LED lamp, λ = 455 nm), and good biaryl yields were obtained (optimum yield = 99%). It is very noteworthy that the photogenerated electrons and holes generated by the photoexcited catalyst were confirmed to be the main active species in the photocatalytic process of the catalyst by radical trapping assay and EPR test. The Pd@g-C₃N₄/TiO₂ material reported in this paper has excellent photocatalytic activity and stability in use, which provides a new reference scheme for wider green synthesis and catalysis.

Metal complexes of thionine, azure C and azure A with copper(II) chloride were prepared using two easy steps as dissolving and then slow evaporation in acetonitrile. Cl⁻ anion in the chloride salt of PTZ dyes was formed [CuCl₃]⁻ with CuCl₂ in the solvent environment, producing its own ionic character (PTZ⁺[CuCl₃]⁻). ThCu, ACCu and AACu complexes were characterized with theoretical computations, thermal, spectral, electrochemical and fluorescence techniques. Such PTZ⁺[Metal Sult]⁻ complexes can be useful for the applications in optoelectronics with their interesting ionic characters.

Structures held together by secondary interactions such as intramolecular or intermolecular hydrogen bonding, electrostatic and π–π interaction without covalent bonds can exhibit new properties such as high orientation, optoelectronics, biocompatibility and reversibility (self-renewal). Recently, interest has been growing surrounding novel molecules fashioned through non-covalent interactions. These molecules have garnered attention due to their significant roles in both physical and chemical applications. However, the formation of complexes between cationic phenothiazine derivative dyes, commonly employed in electrochemical studies, and diverse metal groups presents a challenge. Therefore, the existing literature contains only a scant number of studies concerning the formation of phenothiazine complexes with metal salts. In this study, metal complexes of thionine, azure C and azure A with copper(II) chloride were prepared using two steps: dissolving and then slow evaporation of dyes-copper(II) chloride in acetonitrile. Besides the theoretical computations, thermal, spectral, electrochemical and fluorescence techniques were performed to determine the characteristics of the monoclinic crystals of Cu–dyes complexes. Cl⁻ ion in the dyes and copper(II) chloride conjugated to form [CuCl₃]⁻, then this anion electrostatically bound to cationic phenothiazine ring bond to be phenothiazine⁺[CuCl₃]⁻. Cu–dye complexes showed interestingly high electron transportation. In addition, prepared Cu–dye complexes have a great potential to be used in optical and spectral applications with extraordinary behaviour of their spectral and fluorescence features.