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The Cossee–Arlman mechanism of nickel-catalyzed oligomerization and dimerization with various N∩N-type ligands was studied using the DFT method. For the L1 ligands (L1 = 2,9-disubstituted 1,10-phenanthroline), the dimerization energy barriers for R = Me and R = Ph are about 17.9 and 15.8 kcal mol−1, respectively. However, the presence of Ph substituents at positions 2 and 9 of the L1 ligand reduces the free energy barriers for the dimerization and trimerization processes by approximately 2.1 and 8.1 kcal mol−1, respectively. Therefore, the Ph substituents prevent the removal of β-H from 1-butene, thus promoting the formation of 1-hexene. This result is consistent with experimental observations. In the case of the L2 ligands (L2 = substituted 2-benzoxazole-pyridines) with R1 = H and R2 = H or Me, and R3 = H, the calculated dimerization energy barriers for the systems (H-H) and (H-Me) are about 12.8 and 20.5 kcal mol−1, respectively. The energy barrier for the system with R1 = H and R2 = R3 = Me (Me-Me) is about 20.9 kcal mol−1. Thus, the activity of these systems towards the formation of 1-butene can be arranged as (H-H) > (H-Me) > (Me-Me). As for L3 ligands (L3 = 2-benzimidazolylpyridine derivatives), six systems with R1 = H, Me, tBu; R2 = H, Me, were studied. The calculated dimerization energy barrier values indicate that the (H-H), (H-Me), and (H-tBu) systems (10.8, 11.1, and 10.9 kcal mol−1, respectively) are more active than the (Me-H), (Me-Me) and (Me-tBu) systems (18.8, 19.1 and 19.0 kcal mol−1, respectively). Finally, for the L4 ligand (L4 = 2-benzoimidazol-8-alkylquinoline derivatives), nine systems were studied, divided into three groups: A system (R1 = H and R2 = H or Me or Et), B system R1 = Me with identical R2 substituents, and C system (R1 = Et with identical R2 substituents). Based on the values of the calculated energy barriers for dimerization and trimerization, the B system shows higher activity than the other systems. [ABSTRACT FROM AUTHOR]

This study presents a comprehensive investigation into the structural, morphological, and electrical properties of sol-gel synthesized Ba0.75Ni0.25Tc0.88Mn0.12O3 perovskite ceramic (BNTMO). The meticulous preparation protocol, involving solvating various precursors, was followed by an extensive characterization employing X-ray diffraction, scanning electron microscopy, and dielectric studies. XRD analysis affirmed the single-phase single-phase cubic structure with Pm-3m space, while SEM revealed a well-defined morphology with an average particle size of 243 nm. The electrical conductivity exploration, elucidated through Jonscher's universal power law, provided insights into charge carrier dynamics, exhibiting semiconductor behavior. Impedance spectroscopy unraveled a distinctive relaxation peak, corroborated by Cole-Cole plots, unveiling a unique charge carrier mechanism. Dielectric studies showcased intriguing polarization dynamics, indicating promising applications in energy storage. The convergence of activation energy values from various analyses underscores the coherence in the charge carrier relaxation process. Overall, our findings contribute to a nuanced understanding of the electrical intricacies of BNTMO, presenting avenues for its utilization in advanced technological applications. Highlight: X-ray diffraction (XRD) confirmed that Ba0.75Ni0.25Tc0.88Mn0.12O3 (BNTMO) has a cubic structure (Pm-3m). Scanning electron microscopy (SEM) showed BNTMO has a well-defined morphology with 243 nm average particle size. BNTMO exhibited semiconductor behavior, with electrical conductivity following Jonscher's universal power law. Impedance spectroscopy showed a relaxation peak and Cole-Cole plots indicated a unique charge carrier mechanism. Dielectric studies suggested potential energy storage applications with consistent activation energy values. [ABSTRACT FROM AUTHOR]

Low-cost carbonaceous materials have been synthesized and explored for the removal of harmful colored pollutants from an aqueous medium. However, most of them are not economically viable under continuous-flow conditions and because of their slow kinetics. In this study, we report an economically viable, magnetically reparable adsorbent material synthesized by incorporating spinel zinc ferrite within a waste-char matrix obtained from municipal solid waste (MSW). X-ray diffraction (XRD), fourier transform infrared (FTIR) spectroscopy, X-ray photoelectron spectroscopy (XPS), transmission electron microscopy (TEM), and elemental mapping analyses confirm the successful incorporation of cube-shaped ZnFe2O4 into the multichannel system of the waste-char matrix. The as-prepared waste-char-ZnFe2O4 possesses a large surface area with multiple functional groups that aid in fast catalysis and in the removal of contaminants. Waste-char-ZnFe2O4 follows pseudo-first-order kinetics with photocatalytic degradation efficiencies of ∼72% and 92% and first-order rate constant (K1) values equal to 0.023 and 0.0039 min−1 for tetracycline and rhodamine B, respectively. The adsorption of model contaminants onto waste-char-ZnFe2O4 is best described by the Langmuir isotherm model with an R2 value of 0.99 and a pseudo-second-order kinetic model with an adsorption capacity of 25 mg g−1. The as-synthesized composite gives excellent results for real water samples with negligible interference due to other salt ions present in water. Moreover, the superparamagnetic nature of ZnFe2O4 facilitates the separation and reusability of the nanocomposite material. The material offers the advantage of converting MSW into a functional and more robust magnetic nanotrap for contaminants. [ABSTRACT FROM AUTHOR]

The Schiff base was synthesized and characterized with Infrared, Raman, UV, fluorescence, and NMR studies. The present work is theoretically investigated using DFT/WB97XD/cc-pVTZ basis set. The local energy decomposition (LED) has been performed using PBE0-D3/deft-TZVP basis set and DLPNO-CCSD(T) coupled cluster level. The DFT was used to define the molecular structure and geometry of the compound. To identify the primary binding sites and weak interactions, compound was subjected to a series of topological analyses, including ELF, LOL, ALIE, and RDG. The UV-Visible spectrum was analyzed using the TD-SCF method. The DFT/WB97XD/cc-pVTZ was used to measure the HOMO-LUMO, MEP, and NLO. The NBO calculations investigate the intermolecular and intramolecular movement of charges, as well as the molecule stability. To determine whether the 4CLBDA molecule has the potential to become a drug, computational drug-likeness studies were conducted. The docking study done against the 6X7Q protein is performed and reported. [ABSTRACT FROM AUTHOR]

In the title compound, C17H12N2O,the quinoxaline moiety shows deviations of 0.0288 (7) to -0.0370 (7) Å from the mean plane (r.m.s. deviation of fitted atoms = 0.0223 Å). In the crystal, corrugated layers two molecules thick are formed by C--H⋯N hydrogen bonds and π-stacking interactions. [ABSTRACT FROM AUTHOR]

AbstractPyridazinone derivatives, 6-aryl-pyridazinone (2a–f) and 2-(N-substituted)-6-aryl-pyridazinone (3a–h) derivatives were synthesized and assessed for cytotoxicity action using brine shrimp assessment method and in silico molecular studies. In silico molecular study of pyridazine derivatives used as NNRTIs and Doravirine is used as reference drug. The compounds were investigated for docking modes onto probable binding sites with HIV reverse transcriptase. The majority of these demonstrated favorable binding interactive connections with the active receptor domain. The majority of the compounds exhibited a remarkable docked binding affinity score when compared with the reference drugs. Among the synthesized pyridazine derivatives, compounds 3a and 3c–h exhibited a good docking score. For the designed compounds, in silico ADME assessment indicated the favorable physicochemical properties to be a suitable drug candidate. The synthesized compounds could serve as a novel alternative in designing safe and effective anti-HIV options with reverse transcriptase inhibitor potential. In the cytotoxicity study, all the compounds were evaluated at dose levels 10, and 20 (μg/mL), and potassium dichromate was used as a reference. Compounds 2c and 2e have shown potent lethality through LC50 2.23 and 3.20 μg respectively. Various compounds, including 2a, 2b, 2d, and 2f have demonstrated significant cytotoxicity. Their LC50 values are 7.58, 6.76, 8.91, and 4.46 μg, respectively. Additionally, compounds 3b and 3d exhibited potent lethality with LC50 values of 4.023 and 4.20 μg. Other compounds, namely 3g, 3f, 3c, 3h, 3a, and 3e, displayed noteworthy cytotoxicity ability13.91, 12.58, 11.91, 11.76, 10.58, 9.76, and 7.46 μg, respectively having LC50 values. This study supports the use of in silico molecular design and the brine shrimp bioassay as a suitable, reliable, and simple method for assessing the bioactivity of compounds. It provides further evidence for their use in medicine. [ABSTRACT FROM AUTHOR]

Background: Alzheimer's disease (AD) is a prevalent neurodegenerative condition characterized by progressive cognitive decline and memory impairment resulting from the degeneration and death of brain neurons. Acetylcholinesterase (AChE) inhibitors are used in primary pharmacotherapy for numerous neurodegenerative conditions, providing their capacity to modulate acetylcholine levels crucial for cognitive function. Recently, quinazoline derivatives have emerged as a compelling model for neurodegenerative disease treatment, showcasing promising pharmacological features. Their unique structural features and pharmacokinetic profiles have sparked interest in their potential efficacy and safety across diverse neurodegenerative disorders. The exposure of quinazoline derivatives as a potential therapeutic way underscores the imperative for continued research exploration. Their multifaceted mechanisms of action and ability to target various pathways implicated in neurodegeneration offer exciting prospects for developing novel, effective, and well-tolerated treatments. Further investigations into their pharmacological activities and precise therapeutic roles are essential to advance our understanding of neurodegenerative disease pathophysiology and promote the development of modern therapeutic strategies to address this critical medical challenge., Methods: Quinazoline derivatives have gained eminent acetylcholinesterase (AChE) inhibitory activity. Their ability to effectively modulate AChE activity makes them promising candidates for treating neurological disorders, particularly Alzheimer's disease (AD). Their intricate molecular structures confer selectivity and affinity for AChE, offering potential for the development of novel therapeutic agents targeting cholinergic pathways. Hence, in this study, we designed, synthesized, and characterized a series of spiro[cycloalakane-1,2'-quinazoline derivatives (1-6) to assess their possible AChE inhibiting ability using docking into the active sites., Results: The AChE inhibitory potential of spiro[cycloalkane-1,2'-quinazoline derivatives (1-6) was explored via docking studies of the AChE active site. The findings revealed significant inhibitory activity and highlighted the promising nature of these derivatives., Conclusion: The synthesized spiro[cycloalkane-1,2'-quinazoline derivatives (1-6) exhibited their notable potential as AChE inhibitors. The observed significant inhibitory activity suggested that these derivatives warrant further exploration as candidates for developing therapeutic agents in AChE inhibitory pathways. This study emphasizes the relevance of quinazoline derivatives in searching for novel treatments for neurological disorders, particularly associated with cholinergic dysfunction, and they could be a useful alternative therapeutic agent., (Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.net.)

In the title compound, C 31 H 24 N 4 O 2 , the di-hydro-quinoxaline units are both essentially planar with the dihedral angle between their mean planes being 64.82 (4)°. The attached phenyl rings differ significantly in their rotational orientations with respect to the di-hydro-quinoxaline planes. In the crystal, one set of C-H⋯O hydrogen bonds form chains along the b -axis direction, which are connected in pairs by a second set of C-H⋯O hydrogen bonds. Two sets of π-stacking inter-actions and C-H⋯π(ring) inter-actions join the double chains into the final three-dimensional structure., (© Abad et al. 2024.)

In the title mol-ecule, C 21 H 17 N 3 O 2 , the five-membered ring is slightly ruffled and dihedral angles between the pendant six-membered rings and the central, five-membered ring vary between 50.78 (4) and 86.78 (10)°. The exocyclic nitro-gen lone pair is involved in conjugated π bonding to the five-membered ring. In the crystal, a layered structure is generated by O-H⋯N and N-H⋯O hydrogen bonds plus C-H⋯π(ring) and weak π-stacking inter-actions., (© Elmoutaouakil Ala Allah et al. 2024.)

A lysine-specific demethylase is an enzyme that selectively eliminates methyl groups from lysine residues. KDM5A, also known as JARID1A or RBP2, belongs to the KDM5 Jumonji histone demethylase subfamily. To identify novel molecules that interact with the LSD5A receptor, we created a quantitative structure-activity relationship (QSAR) model. A group of 435 compounds was used in a study of the quantitative relationship between structure and activity to guess the IC50 values for blocking LASD5A. We used a genetic algorithm-multilinear regression-based quantitative structure-activity connection model to forecast the bioactivity ( P IC 50 ) of 1615 food and drug administration pharmaceuticals from the zinc database with the goal of repurposing clinically used medications. We used molecular docking, molecular dynamic simulation modelling, and molecular mechanics generalised surface area analysis to investigate the molecule's binding mechanism. A genetic algorithm and multi-linear regression method were used to make six variable-based quantitative structure-activity relationship models that worked well ( R 2 = 0.8521, Q 2 LOO = 0.8438, and Q 2 LMO = 0.8414). ZINC000000538621 was found to be a new hit against LSD5A after a quantitative structure-activity relationship-based virtual screening of 1615 zinc food and drug administration compounds. The docking analysis revealed that the hit molecule 11 in the KDM5A binding pocket adopted a conformation similar to the pdb-6bh1 ligand (docking score: -8.61 kcal/mol). The results from molecular docking and the quantitative structure-activity relationship were complementary and consistent. The most active lead molecule 11, which has shown encouraging results, has good absorption, distribution, metabolism, and excretion (ADME) properties, and its toxicity has been shown to be minimal. In addition, the MTT assay of ZINC000000538621 with MCF-7 cell lines backs up the in silico studies. We used molecular mechanics generalise borne surface area analysis and a 200-ns molecular dynamics simulation to find structural motifs for KDM5A enzyme interactions. Thus, our strategy will likely expand food and drug administration molecule repurposing research to find better anticancer drugs and therapies.Communicated by Ramaswamy H. Sarma.

In the title compound, C 31 H 24 N 4 O 2 , the quinoxaline units are distinctly non-planar and twisted end-to-end. In the crystal, C-H⋯O and C-H⋯N hydrogen bonds link the mol-ecules into chains extending along the a -axis direction. The chains are linked through π-stacking inter-actions between inversion-related quinoxaline moieties., (© Abad et al. 2024.)