Rapidly, highly yielded and green synthesis of dihydrotetrazolo[1,5‐ a ]pyrimidine derivatives in aqueous media using recoverable Pd (II) thiazole catalyst accelerated by ultrasonic: Computational 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.

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.

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.

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.

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

In this study, we are interested in preparing Fe(III), Pd(II), and Cu(II) complexes from new thiazole derivatives. All syntheses were elaborately elucidated to estimate their molecular and structural formulae, which agreed with those of mononuclear complexes. The square-planer geometry of Pd(II) complex (MATYPd) was the starting point for its use as a heterocatalyst in preparing pyrazole-4-carbonitrile derivatives 4a-o using ultrasonic irradiation through a facile one-pot reaction. The simple operation, short-time reaction (20 min), and high efficiency (97%) were the special advantages of this protocol. Furthermore, this green synthesis strategy was advanced by examination of the reusability of the catalyst in four consecutive cycles without significant loss of catalytic activity. The new synthesis strategy presented remarkable advantages in terms of safety, simplicity, stability, mild conditions, short reaction time, excellent yields, and use of a H₂O solvent. This catalytic protocol was confirmed by the density functional theory (DFT) study, which reflected the specific characteristics of such a complex. Logical mechanisms have been suggested for the successfully exerted essential physical parameters that confirmed the superiority of the Pd(II) complex in the catalytic role. Optical band gap, electrophilicity, and electronegativity features, which are essential parameters for the catalytic behavior of the Pd(II) complex, are based mainly on the unsaturated valence shell of Pd(II).