Development of New Thiazole Complexes as Powerful Catalysts for Synthesis of Pyrazole-4-Carbonitrile Derivatives under Ultrasonic Irradiation Condition Supported by DFT Studies

Efficient extraction of nickel from chloride system using a cleaner extractant: Taking the example of processing nickel-aluminum slag remaining from spent hydroprocessing catalysts

The efficient recovery of nickel from chloride systems has long presented a challenge in the field. While solvent extraction is a viable approach, conventional extractants have been associated with drawbacks such as a high requirement for chloride ions and substantial consumption of acids and alkalis. In response to these challenges, this investigation developed and synthesized a novel thiazole-based extractant, N, N-Bis(4-thiazolylmethyl)octylamine (NNBT), tailored for the selective extraction of nickel from chloride systems. Findings from the study indicate that the nitrogen atom situated on the benzylamine framework within NNBT can interact synergistically with the chelating thiazole ring, facilitating effective nickel extraction and notably reducing the need for chloride ions. Furthermore, the extractant can be regenerated using deionized water, thereby obviating the necessity for additional consumption of acids and alkalis. Following the validation of NNBT as an environmentally sustainable and efficient nickel extractant within the chloride ion system, it was successfully employed to selectively and effectively extract nickel from the nickel-aluminum slag of spent HDP catalyst. The extracted nickel and aluminum were subsequently processed into electroplated nickel chloride and polyaluminum chloride, respectively, meeting the national standards of China. These outcomes underscore the eco-friendliness and promise of NNBT for nickel extraction from chloride systems.

Design, spectroscopic characterizations, and biological investigation of oxospiro[chromine-4,3-indolene]-based compounds as promising antiproliferative EGFR inhibitors and antimicrobial agents

Utilizing microwave heating and an aqueous saturated solution of K2CO3 as a catalyst, a rapidone-pot synthesis of oxospiro[chromene-4.3-indoline] derivatives was produced in high yields. The experimental results confirmed that the saturated solution of K2CO3 gives outstanding yield to dangerous metals and strong bases during investigations into high-performance catalysts. The used catalyst is green, affordable, incredibly mild, and widely accessible. However, it generates samples, reduces the amount of byproducts, and is expected to be used in industrial-scale heterocyclic derivatives. New oxospiro[chromene-4.3-indoline] derivatives have been created from various isatin by condensing with various phenols. The biological activities results showed that when compared to erlotinib, the derivatives 3b, 4b, 5b, and 6b were the most effective analogues on A549, MCF-7, HepG-2, and HCT-116 cells, with an IC50 range of 3.32 to 11.88 µM. In A549 cells, compounds 3b, 4b, 5b, and 6b induced apoptosis, as shown by the up-regulation of Bax, the up-regulation of Bcl-2, and the stimulation of caspase-3 and -9. With IC50 value of 0.19 ± 0.09, compound3b was demonstrated to be the most effective against EGFRWT. Compounds 4b and 6b have good antibacterial activity toward Staphylococcus aureus, comparable to ciprofloxacin, and about half as much activity as ampicillin, according to the MIC value. Compound 6b's MIC is about 25% lower than clotrimazole drug. The in silico molecular docking outcomes of compounds 3b, 4b, 5b, and 6b in the EGFR active site depicted their ability to adopt essential binding interactions compared to the reference Erlotinib. Moreover, the investigation of the physicochemical properties of the most promising dual acting antiproliferative and antimicrobial compounds 4b and 6b through the egg-boiled method illustrated acceptable lipophilicity, GIT absorption, and blood-brain barrier penetration characteristics.

Application of Photocatalysis and Sonocatalysis for Treatment of Organic Dye Wastewater and the Synergistic Effect of Ultrasound and Light

Organic dyes play vital roles in the textile industry, while the discharge of organic dye wastewater in the production and utilization of dyes has caused significant damage to the aquatic ecosystem. This review aims to summarize the mechanisms of photocatalysis, sonocatalysis, and sonophotocatalysis in the treatment of organic dye wastewater and the recent advances in catalyst development, with a focus on the synergistic effect of ultrasound and light in the catalytic degradation of organic dyes. The performance of TiO₂-based catalysts for organic dye degradation in photocatalytic, sonocatalytic, and sonophotocatalytic systems is compared. With significant synergistic effect of ultrasound and light, sonophotocatalysis generally performs much better than sonocatalysis or photocatalysis alone in pollutant degradation, yet it has a much higher energy requirement. Future research directions are proposed to expand the fundamental knowledge on the sonophotocatalysis process and to enhance its practical application in degrading organic dyes in wastewater.

One-pot multicomponent synthesis of benzophenazine tethered tetrahydropyridopyrimidine derivatives

A simple, facile, and efficient green methodology has been developed for the synthesis of benzophenazine tethered tetrahydropyridopyrimidine derivatives by the one-pot four-component reaction of cinnamaldehyde/crotonaldehyde, 2-hydroxy-1,4-naphthoquinone, 1,3-dimethyl-6-amino uracil, and o-phenylenediamine in ethanol medium under reflux conditions using p-TSA as a catalyst. In this environmentally benign methodology, three C-N and two C-C bonds are formed in one pot. The hybrid products have three bioactive moieties such as benzophenazine, tetrahydropyridine, and pyrimidine. Operational simplicity, metal-free conditions, wide substrate scope, readily available starting materials, moderate to good yields of the desired products, presence of pharmaceutically active moieties, and easy purification process are the notable features of this methodology.

Design, Synthesis, Spectroscopic Inspection, DFT and Molecular Docking Study of Metal Chelates Incorporating Azo Dye Ligand for Biological Evaluation

A new heterocyclic azo dye ligand (L) was synthesized by the combination of 4-amino antipyrine with 4-aminophenol. The new Cr(III), Mn(II), Fe(III), Co(II), Ni(II), Cu(II), Zn(II), and Cd(II) complexes were synthesized in excellent yields. The metal chelate structures were elucidated using elemental analyses, FT-IR, ¹H-NMR, mass, magnetic moment, diffused reflectance spectral and thermal analysis (TG-DTG), and molar conductivity measurement. According to the FT-IR study, the azo dye ligand exhibited neutral tri-dentate behavior, binding to the metal ions with the azo N, carbonyl O, and protonated phenolic OH. The ¹H-NMR spectral study of the Zn(II) complex supported the coordination of the zo dye ligand without proton displacement of the phenolic OH. Diffused reflectance and magnetic moment studies revealed the octahedral geometry of the complexes, as well as their good electrolytic nature, excepting the Zn(II) and Cd(II) complexes, which were nonelectrolytes, as deduced from the molar conductivity study. The theoretical calculations of optimized HOMO-LUMO energies, geometrical parameters, electronic spectra, natural atomic charges, 3D-plots of MEP, and vibrational wavenumbers were computed and elucidated using LANL2DZ and 6-311G (d, p) basis sets of density functional theory (DFT) with the approach of B3LYP DFT and TD-DFT methods. The ligand and complexes have been assayed for their antimicrobial activity and compared with the standard drugs. Most of the complexes have manifested excellent antimicrobial activity against various microbial strains. A molecular docking investigation was also performed, to acquire more information about the binding mode and energy of the ligand and its metal complexes to the Escherichia coli receptor using molecular docking. Altogether, the newly created ligand and complexes showed positive antibacterial effects and are worth future study.

Development of New Azomethine Metal Chelates Derived from Isatin: DFT and Pharmaceutical Studies

Through the condensation of isatin (indoline-2, 3-dione) and aniline in a 1:1 ratio, a Schiff base ligand was synthesized and characterized via (¹H-NMR, mass, IR, UV-Vis) spectra. Elemental analyses, spectroscopy (¹H-NMR, mass, UV-Vis), magnetic susceptibility, molar conductivity, mass spectra, scanning electron microscope (SEM), and thermal analysis have all been used to characterize a series of Cr(III), Mn(II), Fe(III), Co(II), Ni(II), Cu(II), Zn(II), and Cd(II) metal complexes derived from the titled ligand. The metal-to-ligand ratio is 1:1, according to the analytical data. The Schiff base ligand displayed bidentate behavior with NO coordination sites when it bonded to metal ions, as seen by the IR spectra. The magnetic moment measurement and UV-Vis spectral investigation showed the octahedral geometry of the Cr(III), Fe(III), Co(II), Ni(II), and Zn(II) complexes, whereas they suggested the tetrahedral geometry of the Mn(II), Cu(II), and Cd(II) complexes. The thermal analysis study confirmed the presence of both hydrated and coordinated water molecules in all the compounds, except for the Mn(II) complex, and showed that the complexes decomposed in three or five decomposition steps leaving the corresponding metal oxide as a residue. The ligand and its metal complexes' antibacterial efficacy were evaluated. The findings showed that the metal complexes had stronger antibacterial properties than the ligand alone. The ligand and its metal complexes' anticancer properties were also investigated. A DFT investigation is also reported to gather information regarding the electronic features of the ligand and its metal complexes. Finally, drug-likeness and ADME characteristics were also calculated as parameters.

Thieno[2,3-b]thiophene Derivatives as Potential EGFRWT and EGFRT790M Inhibitors with Antioxidant Activities: Microwave-Assisted Synthesis and Quantitative In Vitro and In Silico Studies

Microwave-assisted synthesis and spectral analysis of certain novel derivatives of 3,4-diaminothieno[2,3-b]thiophene-2,5-dicarbonitrile 1-7 were carried out. Compounds 1-7 were examined for cytotoxicity against MCF-7 and A549 cell lines using the quantitative MTT method, and gefitinib and erlotinib were used as reference standards. Compounds 1-7 were shown to be more active than erlotinib against the two cell lines tested. Compound 2 outperformed regular erlotinib by 4.42- and 4.12-fold in MCF-7 and A549 cells, respectively. The most cytotoxic compounds were subsequently studied for their suppression of kinase activity using the homogeneous time-resolved fluorescence assay versus epidermal growth factor receptor (EGFR^WT) and EGFR^790M. With IC₅₀ values of 0.28 ± 0.03 and 5.02 ± 0.19, compound 2 was demonstrated to be the most effective against both forms of EGFR. Furthermore, compound 2 also had the best antioxidant property, decreasing the radical scavenging activity by 78%. Molecular docking research, on the other hand, was carried out for the analyzed candidates (1-7) to study their mechanism of action as EGFR inhibitors. In silico absorption, distribution, metabolism, excretion, and toxicity tests were also performed to explain the physicochemical features of the examined derivatives.

Microwave-assisted synthesis, spectroscopic characterization, and biological evaluation of fused thieno[2,3-d]pyrimidines as potential anti-cancer agents targeting EGFRWT and EGFRT790M

Epidermal growth factor receptor (EGFR) is a transmembrane protein tyrosine kinase that is usually overexpressed in many types of cancers. In the present study, an effort was done in synthesis of new 3,4-diaminothieno[2,3-b] thiophene-2,5-dicarbonitrile derivatives 2-8, assisted by a microwave device. Different spectroscopic instruments were used for their analysis and confirmed their chemical structures. The antimicrobial properties of the produced compounds were investigated and found to be promising. Next, they were tested for cytotoxicity against MCF-7, HepG-2, HCT-116, and A549 cell lines. Moreover, in vitro cytotoxicity evaluation against well-known standards, namely, gefitinib and erlotinib was achieved using MTT method. The obtained compounds (2-8) were found to be more effective against the two tested cancer cell lines than erlotinib. In MCF-7 and A549 cells, compound 3 was found to be 4.42 and 4.12 times more active than erlotinib, respectively. The activity of radical scavenging was inhibited by 78%. The most cytotoxic compounds were subsequently studied for their kinase inhibitory effect against EGFR^WT and EGFR^T790M using the HTRF assay. Compound 3 was shown to be the most powerful against both kinds of EGFR, with IC₅₀ values of 0.28 and 5.02. Furthermore, compound 2 demonstrated the highest antioxidant activity as it has a radical scavenging activity of 78%. Compounds 2,6,7 and 8 revealed to be the most safe compounds, none hepatotoxic, none carcinogenic, none immunotoxic, none mutagenic and none cytotoxic.

5-N-Arylaminothiazoles with pyridyl groups and their first-row transition metal complexes: synthesis, photophysical properties, and Zn sensing

A series of 5-N-arylaminothiazoles were synthesized with facile diversity-oriented synthesis from readily available starting materials via the reaction of thioamide dianions and thioformamides. The introduction of various substituents at the 2-position of a thiazole ring (i.e., 2-pyridyl, 4-methylpyridyl, and phenyl groups) and on the nitrogen atom (i.e., p-tolyl and phenyl groups) significantly influenced the absorption and emission spectra of the isolated compounds. X-ray analysis confirmed that the substituents at the amino site were twisted from a thiazole ring, while the formation of its nickel complex showed dinuclear metal complexes bridged with chlorine atoms. Moreover, the formation of zinc-thiazole complexes showed enhanced emission properties in solution and noticeable emission in a solid state. In addition, thiazole-bridged dypyrromethene type ligands showed high selectivity toward Zn+2, which make them good candidates for zinc sensing.

Development of 1-(4-(Substituted)piperazin-1-yl)-2-((2-((4-methoxybenzyl)thio)pyrimidin-4-yl)oxy)ethanones That Target Poly (ADP-Ribose) Polymerase in Human Breast Cancer Cells

A number of uracil amides cleave poly (ADP-ribose) polymerase and therefore novel thiouracil amide compounds were synthesized and screened for the loss of cell viability in a human-estrogen-receptor-positive breast cancer cell line. The synthesized compounds exhibited moderate to significant efficacy against human breast cancer cells, where the compound 5e IC₅₀ value was found to be 18 μM. Thouracil amide compounds 5a and 5e inhibited the catalytical activity of PARP1, enhanced cleavage of PARP1, enhanced phosphorylation of H2AX, and increased CASPASE 3/7 activity. Finally, in silico analysis demonstrated that compound 5e interacted with PARP1. Hence, specific thiouracil amides may serve as new drug-seeds for the development of PARP inhibitors for use in oncology.

Fabrication, DFT Calculation, and Molecular Docking of Two Fe(III) Imine Chelates as Anti-COVID-19 and Pharmaceutical Drug Candidate

Two tetradentate dibasic chelating Schiff base iron (III) chelates were prepared from the reaction of 2,2′-((1E,1′E)-(1,2-phenylenebis(azanylylidene))bis(methanylylidene))bis(4-bromophenol) (PDBS) and 2,2′-((1E,1′E)-((4-chloro-1,2-phenylene)bis(azanylylidene))-bis(methanylylidene))bis(4-bromophenol) (CPBS) with Fe³⁺ ions. The prepared complexes were fully characterized with spectral and physicochemical tools such as IR, NMR, CHN analysis, TGA, UV-visible spectra, and magnetic moment measurements. Moreover, geometry optimizations for the synthesized ligands and complexes were conducted using the Gaussian09 program through the DFT approach, to find the best structures and key parameters. The prepared compounds were tested as antimicrobial agents against selected strains of bacteria and fungi. The results suggests that the CPBSFe complex has the highest activity, which is close to the reference. An MTT assay was used to screen the newly synthesized compounds against a variety of cell lines, including colon cancer cells, hepatic cellular carcinoma cells, and breast carcinoma cells. The results are expressed by IC50 value, in which the 48 µg/mL value of the CPBSFe complex indicates its success as a potential anticancer agent. The antioxidant behavior of the two imine chelates was studied by DPPH assay. All the tested imine complexes show potent antioxidant activity compared to the standard Vitamin C. Furthermore, the in vitro assay and the mechanism of binding and interaction efficiency of the tested samples with the receptor of COVID-19 core protease viral protein (PDB ID: 6lu7) and the receptor of Gram-negative bacteria (Escherichia coli, PDB ID: 1fj4) were investigated using molecular docking experiments.

Microwave-Assisted Synthesis, Biological Activity Evaluation, Molecular Docking, and ADMET Studies of Some Novel Pyrrolo [2,3-b] Pyrrole Derivatives

Novel pyrrolo [2,3-b] pyrrole derivatives were synthesized and their hypolipidemic activity was assessed in hyperlipidemic rats. The chemical structures of the new derivatives were confirmed through spectral analysis. Compounds 5 and 6 were revealed to be the most effective hypolipidemic agents, with considerable hypocholesterolemic and hypotriglyceridemic effects. They appear to be promising candidates for creating new powerful derivatives with anti-atherosclerotic and hypolipidemic properties. As for antimicrobial activity, some of the tested compounds showed moderate activity against Pseudomonas aeruginosa: compound 2 revealed an MIC value of 50 μg/mL, compared to 25 μg/mL for ciprofloxacin. Compound 3 showed good antimicrobial activity against Staphylococcus aureus, comparable to ciprofloxacin, and roughly half the activity of ampicillin, according to MIC values. Compound 2 has an MIC approximately 25% of that of clotrimazole against Candida albicans. Compound 2 also showed the highest antioxidant activity with 59% inhibition of radical scavenging activity. Additionally, the cytotoxic activity of these new derivatives 1–7 was investigated and most of them showed good anticancer activity against the three tested cell lines.