Complexes 2c Research Articles

Antimicrobial Activity of Anionic Bis(N-Heterocyclic Carbene) Silver Complexes

The antimicrobial properties of a series of anionic bis(carbene) silver complexes Na3[Ag(NHCR)2] were investigated (2a–2g and 2c′, where NHCR is a 2,2′-(imidazol-2-ylidene)dicarboxylate-type N-heterocyclic carbene). The complexes were synthesized by the interaction of imidazolium dicarboxylate compounds with silver oxide in the presence of aqueous sodium hydroxide. Complexes 2f,g were characterized analytically and spectroscopically, and the ligand precursor 1f and complexes 2c and 2g were structurally identified by X-ray diffraction methods. The anions of 2c and 2g, [Ag(NHCR)2]3−, showed a typical linear disposition of Ccarbene-Ag-Ccarbene atoms and an uncommonly eclipsed conformation of carbene ligands. The antimicrobial properties of complexes 2a–g, which contains chiral (2b–2e and 2c′) and non-chiral derivatives (2a,f,g), were evaluated against Gram-negative bacteria, Escherichia coli and Pseudomonas aeruginosa, and a Gram-positive bacterium, Staphylococcus aureus. From the observed values of the minimal inhibitory concentration and minimal bactericidal concentration, complexes 2a and 2b showed the best antimicrobial activity against all strains. An interesting chirality–antimicrobial relationship was found, and eutomer 2c′ showed better activity than its enantiomer 2c against the three bacteria. Furthermore, these complexes were investigated experimentally and theoretically by 109Ag nuclear magnetic resonance, and the electronic and steric characteristics of the dianionic carbene ligands were also examined.

Antidiabetic and Antihyperlipidemic Activities and Molecular Mechanisms of Phyllanthus emblica L. Extract in Mice on a High-Fat Diet.

We planned to explore the protective activities of extract of Phyllanthus emblica L. (EPE) on insulin resistance and metabolic disorders including hyperlipidemia, visceral obesity, and renal dysfunction in high-fat diet (HFD)-progressed T2DM mice. Mice treatments included 7 weeks of HFD induction followed by EPE, fenofibrate (Feno), or metformin (Metf) treatment daily for another 4-week HFD in HFD-fed mice. Finally, we harvested blood to analyze some tests on circulating glycemia and blood lipid levels. Western blotting analysis was performed on target gene expressions in peripheral tissues. The present findings indicated that EPE treatment reversed the HFD-induced increases in blood glucose, glycosylated HbA1C, and insulin levels. Our findings proved that treatment with EPE in HFD mice effectively controls hyperglycemia and hyperinsulinemia. Our results showed that EPE reduced blood lipid levels, including a reduction in blood triglyceride (TG), total cholesterol (TC), and free fatty acid (FFA); moreover, EPE reduced blood leptin levels and enhanced adiponectin concentrations. EPE treatment in HFD mice reduced BUN and creatinine in both blood and urine and lowered albumin levels in urine; moreover, EPE decreased circulating concentrations of inflammatory NLR family pyrin domain containing 3 (NLRP3) and kidney injury molecule-1 (KIM-1). These results indicated that EPE displayed antihyperglycemic and antihyperlipidemic activities but alleviated renal dysfunction in HFD mice. The histology examinations indicated that EPE treatment decreased adipose hypertrophy and hepatic ballooning, thus contributing to amelioration of lipid accumulation. EPE treatment decreased visceral fat amounts and led to improved systemic insulin resistance. For target gene expression levels, EPE enhanced AMP-activated protein kinase (AMPK) phosphorylation expressions both in livers and skeletal muscles and elevated the muscular membrane glucose transporter 4 (GLUT4) expressions. Treatment with EPE reduced hepatic glucose-6-phosphatase (G6Pase) and phosphoenolpyruvate carboxykinase (PEPCK) expressions to suppress glucose production in the livers and decreased phosphorylation of glycogen synthase kinase 3β (GSK3β) expressions to affect hepatic glycogen synthesis, thus convergently contributing to an antidiabetic effect and improving insulin resistance. The mechanism of the antihyperlipidemic activity of EPE involved a decrease in the hepatic phosphorylation of mammalian target of rapamycin complex C1 (mTORC1) and p70 S6 kinase 1 (S6K1) expressions to improve insulin resistance but also a reduction in hepatic sterol regulatory element binding protein (SREBP)-1c expressions, and suppression of ACC activity, thus resulting in the decreased fatty acid synthesis but elevated hepatic peroxisome proliferator-activated receptor (PPAR) α and SREBP-2 expressions, resulting in lowering TG and TC concentrations. Our results demonstrated that EPE improves insulin resistance and ameliorates hyperlipidemia in HFD mice.

In the search for new gold metalloantibiotics: In vitro evaluation of Au(III) (C^S)-cyclometallated complexes

A series of (C^S)-cyclometallated Au(III) cationic complexes of general formula [Au(dppta)(dtc)]+, [Au(dppta)(azmtd)]+ and [Au(dppta)(azc)Cl]+ (dppta = N,N-diisopropyl-P,P-diphenylphosphinothioic amide-κ2C,S; dtc = dithiocarbamate-κ2S,S′; azc = azolium-2-dithiocarboxylate-κ1S; azmdt = azol(in)ium-2-(methoxy)methanedithiol-κ2S,S′) were synthetized and tested against a panel of bacterial strains belonging to different Gram-positive and Gram-negative species of the ESKAPE group of pathogens. Among the tested compounds, complex 4c had the higher Therapeutic Index (TI) against multidrug resistant strains of S. aureus, S. epidermidis and A. baumannii, showing a more favourable cytotoxicity profile than the reference gold metalloantibiotic Auranofin.© 2024 xxxxxxxx. Hosting by Elsevier B.V. All rights reserved.

Lie algebras arising from two-periodic projective complex and derived categories

Let A be a finite-dimensional C-algebra of finite global dimension and A be the category of finitely generated right A-modules. By using of the category of two-periodic projective complexes C2(P), we construct the motivic Bridgeland's Hall algebra for A, where structure constants are given by Poincaré polynomials in t, then construct a C-Lie subalgebra g=n⊕h at t=−1, where n is constructed by stack functions about indecomposable radical complexes, and h is by contractible complexes. For the stable category K2(P) of C2(P), we construct its moduli spaces and a C-Lie algebra g˜=n˜⊕h˜, where n˜ is constructed by support-indecomposable constructible functions, and h˜ is by the Grothendieck group of K2(P). We prove that the natural functor C2(P)→K2(P) together with the natural isomorphism between Grothendieck groups of A and K2(P) induces a Lie algebra isomorphism g≅g˜. This makes clear that the structure constants at t=−1 provided by Bridgeland in [5] in terms of exact structure of C2(P) precisely equal to that given in [30] in terms of triangulated category structure of K2(P).

Long-term effects of nitrogen and phosphorus fertilization on profile distribution and characteristics of dissolved organic matter in fluvo-aquic soil

Dissolved organic matter (DOM) drives numerous biogeochemical processes (e.g. carbon cycling) in agro-ecosystems and is sensitive to fertilization management. Nevertheless, changes in the quantity and quality of DOM in the vertical soil profile following long-term continuous nitrogen (N) and phosphorus (P) inputs remain unclear. In this study, the contents and optical characteristics of DOM along a 2-m soil profile were investigated using a 40-year wheat/maize rotation combined with experiments using different N and P fertilization rates in the North China Plain. The results revealed that the dissolved organic carbon (DOC) content decreased with an increase in soil depths. Compared with that in the control (no fertilization), 40-year N, P, and N + P additions increased the soil DOC content by 26%–69%, except for 270-kg N, and 67.5-kg P treatments. N + P application resulted in higher DOC contents than N-alone and P-alone applications. N, P, and N + P inputs increased or did not affect the aromaticity and hydrophobicity of DOM at 0–40 cm but reduced them from 40 to 200 cm. Compared with that in the control, N, P, and N + P inputs enhanced the content of humic acid-like substances (C1+C2+C3+C4) and decreased the content of protein-like substance (C5). C1 was the dominant component among the five DOM, representing the microbial humic component. Optical indices also indicated that soil DOM primarily originated from microbial sources. Nutrient addition accelerated transformation between complex C1 and simple C5 via promoting microbial activities. These results imply that N and P fertilizers increased the DOM content and altered its composition, thereby potentially affecting the stability of soil organic matter in the agroe-cosystems.

Nickel complexes bearing quinoline derived NNS donor ligands as catalytic activators for N-alkylation of anilines with alcohols.

Herein, we have reported a new series of NNS-donor ligands coordinated Ni(II) complexes and utilized them as catalytic activator to synthesize N-alkylated aminesand 1,2-disubstituted benzimidazoles. Theseparate reaction of [C9H6N-NH-C(O)-CH2-S-Ar] [Ar = C6H5 (L1); C6H4Cl-4 (L2);C6H4Me-4 (L3) and C6H4-OMe-4 (L4)]with Ni(OAc)2 in methanol at 80°C for 3 hours resulted in octahedral nickel complexes [(L1-H)2Ni] (C1), [(L2-H)2Ni] (C2), [(L3-H)2Ni] (C3), and [(L4-H)2Ni] (C4), respectively. All compounds have been characterized by micro and spectroscopic analysis. The molecular structure of complexes C1-C3 has also been determined by single crystal X-ray diffraction data. The utility of complexes C1-C4 were evaluated for the N-alkylation of aniline with benzyl alcohols, and for 1,2-disubstituted benzimidazoles synthesis. The obtained results indicate that complex C1 showed better catalytic activity in both N-alkylation of amines with benzyl alcohols [catalyst loading: 2.0 mol%; Yield up to 92%], and for 1,2-disubstituted benzimidazoles derivatives [catalyst loading: 2.0 mol%; Yield up to 94%)]. The mechanistic studies suggested that the reaction works through hydrogen borrowing from benzyl alcohol and its subsequent utilization for in situ reduction of imine. The experimentally observed catalytic reactivity patterns of complexes C1-C4 have found in good agreement with the HOMO-LUMO energy gaps obtained by DFT analysis of corresponding complexes.

Fe(µ2-OH)6]3- Linked Fe3O Triads: Mössbauer Evidence for Trigonal µ3-O2- or µ3-OH- Groups in Bridged versus Unbridged Complexes.

The syntheses, coordination chemistry, and Mössbauer spectroscopy of hepta-iron(III) complexes using derivatised salicylaldoxime ligands from two categories; namely, 'single-headed' (H2L) and 'double-headed' (H4L) salicylaldoximes are described. All compounds presented here share a [Fe3-µ3-O] core in which the iron(III) ions are µ3-hydroxo-bridged in the complex C1 and µ3-oxo-bridged in C2 and C3. Each compound consists of 2 × [Fe3-µ3-O] triads that are linked via a central [Fe(µ2-OH)6]3- ion. In addition to the charge balance and microanalytical evidence, Mössbauer measurements support the fact that the triads in C1 are µ3-OH bridged and are µ3-O bridged in C2 and C3.

Co-targeting CDK 4/6 and C-MYC/STAT3/CCND1 axis and inhibition of tumorigenesis and epithelial-mesenchymal-transition in triple negative breast cancer by Pt(II) complexes bearing NH3 as trans-co-ligand

In search of potential anticancer agents, we synthesized SNO-donor salicylaldimine main ligand-based Pt(II) complexes bearing NH3 as co-ligand at trans-position (C1-C6). These complexes showed similarity in structure with transplatin as the two N donor atoms of the main ligand and NH3 co-ligand were coordinated to Pt in trans position to each other. Each complex with different substituents on the main ligand was characterized thoroughly by detailed spectroscopic and spectrophotometric methods. Four of these complexes were studied in solid state by single crystal X-ray analysis. The stability of reference complex C1 was measured in solution state in DMSO‑d6 or its mixture with D2O using 1H NMR methods. These complexes were further investigated for their anticancer activity in triple-negative-breast (TNBC) cells including MDA-MB-231, MDA-MB-468 and MDA-MB-436 cells. All these complexes showed satisfactory cytotoxic effect as revealed by the MTT results. Importantly, the highly active complex C4 anticancer effect was compared to the standard chemotherapeutic agents including cisplatin, oxaliplatin and 5-fluorouracil (5-FU). Functionally, C4 suppressed invasion, spheroids formation ability and clonogenic potential of cancer cells. C4 showed synergistic anticancer effect when used in combination with palbociclib, JQ1 and paclitaxel in TNBC cells. Mechanistically, C4 inhibited cyclin-dependent kinase (CDK)4/6 pathway and targeted the expressions of MYC/STAT3/CCND1/CNNE1 axis. Furthermore, C4 suppressed the EMT signaling pathway that suggested a role of C4 in the inhibition of TNBC metastasis. Our findings may pave further in detailed mechanistic study on these complexes as potential chemotherapeutic agents in different types of human cancers.

C[sbnd]H activation of furanyl and thiofuranyl substrates catalyzed by trans-dichloro[1-cinnamyl-3-arylmethyl-benzimidazol-2-yliden]pyridine palladium(II) complexes

The present study explores the potential of six NHC-palladium(II) complexes derived from N-cinnamyl-N’-alkylbenzimidazolium salts, namely trans-dichloro[1,3-dicinnamyl-benzimidazol-2-yliden]pyridine palladium(II) (3a), trans-dichloro[1-cinnamyl-3-benzyl-benzimidazol-2-yliden]pyridine palladium(II) (3b), trans-dichloro[1-cinnamyl-(fluorobenzyl)-benzimidazol-2-yliden]pyridine palladium(II) (2-fluorobenzyl 3c, 3-fluorobenzyl 3d and 4-fluorobenzyl 3e,) and trans-dichloro[1-cinnamyl-(4-nitrobenzyl)-benzimidazol-2-yliden]pyridine palladium(II) (3f), as precatalyst for the cross-coupling reactions between furanyl and thiofuranyl derivatives and arylbromides via CH activation of the heterocycles. The structure of the six palladium(II) complexes has been elucidated through the use of multinuclear NMR, FT-IR and mass spectroscopy. Furthermore, the square-planar geometry of the organometallic ion was confirmed by single crystal X-ray diffraction study carried out on complex 3c. The latter complex proved to be the most effective precatalyst agent, with observed conversions higher than 78% when 4-bromoacetophenone and 1-bromonaphthalene were employed.

Digital-Twin-Assisted Skill Learning for 3C Assembly Tasks.

The utilization of robots in computer, communication, and consumer electronics (3C) assembly has the potential to significantly reduce labor costs and enhance assembly efficiency. However, many typical scenarios in 3C assembly, such as the assembly of flexible printed circuits (FPCs), involve complex manipulations with long-horizon steps and high-precision requirements that cannot be effectively accomplished through manual programming or conventional skill-learning methods. To address this challenge, this article proposes a learning-based framework for the acquisition of complex 3C assembly skills assisted by a multimodal digital-twin environment. First, we construct a fully equivalent digital-twin environment based on the real-world counterpart, equipped with visual, tactile force, and proprioception information, and then collect multimodal demonstration data using virtual reality (VR) devices. Next, we construct a skill knowledge base through multimodal skill parsing of demonstration data, resulting in primitive policy sequences for achieving 3C assembly tasks. Finally, we train primitive policies via a combination of curriculum learning, residual reinforcement learning, and domain randomization methods and transfer the learned skill from the digital-twin environment to the real-world environment. The experiments are conducted to verify the effectiveness of our proposed method.

Catalytic ethylene oligomerization reactions of terpyridine (NNN)-based nickel(II) complexes – Studies on catalytical intermediates

The present work demonstrates the synthesis of four new terpyridine (tpy) ligands (4′-(4-(pent-4-en-1-yloxy)phenyl)-2,2′:6′,2″-terpyridine (3), 4-((3-([2,2′:6′,2″-terpyridin]-4′-yl)phenoxy)methyl)benzonitrile (4), 4′-(3-(pent-4-en-1-yloxy)phenyl)-2,2′:6′,2″-terpyridine (5), and 4-([2,2′:6′,2″-terpyridin]-4′-yl)phenyl 5-chlorothiophene-2-carboxylate (6)), the corresponding Ni(II) complexes (3C–6C), and their usage as catalysts in ethylene oligomerization reactions. The purity of all the ligands and the complexes employed in the present study was assessed by various analytical and spectroscopic techniques. One of the tpy-Ni(II) complexes (6C) was structurally characterized by single-crystal XRD analysis. Notably, the nature of ligands as well as temperature strongly influence the organic product distribution, i.e. elevated temperatures facilitate C6 product in significant amounts. Among all the complexes, the Ni(II)-tpy (6C) substituted with 5-chloro-thiophenyl group at 4′ position showed high selectivity for 1-hexene (C6, 80%) at room temperature and 1-octene (C8, 91%) at elevated temperatures. Though both mechanistic pathways were proved to be feasible, the present study is also intended to identify and analyze the key intermediate species of the reactions. In order to shed more light on mechanistic aspects, ethylene insertion reactions were compared with selected platinacycloalkane complexes in a high-pressure autoclave reactor, and the formation of large metallacycloalkane species was observed in the mass spectral data.

In-vitro antioxidant and antidiabetic effects of Rorippa indica (L.) extract and fractions with molecular docking, dynamics simulation, ADMET, and PASS studies

Rorippa indica (L.) is an annual herb of the Brassicaceae family that has the potential as a traditional medicine. In this research, the antioxidant, and antidiabetic effects of R. indica were systematically studied by computational and experimental techniques. The prepared methanolic extract of R. indica (MRI) was fractionated with petroleum ether (PRI), dichloromethane (DRI), ethyl acetate (ERI), and distilled water (WRI). The total phenols (TPC) and flavonoids (TFC) of the extract and fractions were measured applying the Folin-Ciocalteu and AlCl3 methods, respectively, and the ERI fraction showed the highest TPC and TFC values. Spectrophotometric techniques estimated the total antioxidant capacity and ERI showed the highest antioxidant (IC50: 30.35±3.58 µg/ml in DPPH, EC50: 24.98±7.11 µg/ml in FRPT) potentials. In an in-vitro antidiabetic investigation, ERI demonstrated maximum α-glucosidase and α-amylase inhibitory action where the IC50 values were 25.13 and 19.96 μg/ml, respectively. Further, the GC‒MS study revealed 23 compounds, among them molecular docking of (±)-Kusunokinin (C2) exhibited the highest binding scores with antioxidant (2HE3) (-6.6 kcal/mol), antidiabetic α-glucosidase (5NN5) (-8.3 kcal/mol), and α-amylase (4GQR) protein (-8.0 kcal/mol), respectively. Molecular dynamics by YASARA demonstrated that the complex C2 had an initial higher RMSD trend, reduced its profile after 30 ns, stabilized after 40 ns, and maintained a stable state until 100 ns. Moreover, the ADMET results depicted the non-hepatotoxic, and well-absorbed behaviour. In contrast, the PASS prediction and drug-likeness data revealed their effectiveness as antioxidant, antidiabetic, and anticancer agents, and excellent oral bioavailability. Overall, the R. indica plant could be an expected source of lead compounds for the discovery and advancement of a fresh potential drug.

Synthesis and anti-cancer investigations of copper(II) complexes based on adenine

Platinum-based chemotherapeutics have played a critical role in oncology for decades. However, their broader utility is hindered by the advent of severe side effects and the emergence of drug resistance. The pursuit of alternative agents, particularly non-platinum (non-Pt) metal complexes, has gained momentum in current research. Designing efficacious non-Pt metal agents that target DNA poses a complex challenge. In this study, we present the strategic design, synthesis, and thorough characterization of two innovative copper(II) complexes leveraging adenine as a ligand, a potential avenue to overcome these challenges. Our investigation demonstrates the superior cytotoxicity of these copper(II) complexes compared to the benchmark cisplatin, with complex C2 exhibiting the most promising anticancer activity, showcasing an impressive IC50 value of 4.51 μM in MGC-803 cells. Mechanistic insights underscore that complex C2 executes its cytotoxic effects by instigating DNA damage, orchestrating cell cycle arrest at the G2 phase, perturbing mitochondrial membrane potential, inducing ROS production, and ultimately triggering apoptotic pathways. These findings significantly emphasize the potential of designing novel adenine-based anticancer metal complexes targeting DNA, portraying a compelling trajectory for advancing anticancer drug development.

Synthesis and characterization of sulfonamide appended rigid phenyl-based and non-rigid 1,4-benzodioxan-based ring systems and their Pt(II) complexes towards potential therapeutic targets

Two novel non-rigid; 1,4-benzodioxan (bzd) based and rigid; 4-methylbiphenyl (4-Mebip) based di-(2-picolyl)amine derived sulfonamide ligands, and their cis-dichloroplatinum(II) complexes have been synthesized. The ligands; L1: N(SO2)(bzd)dpa and L2: N(SO2)(4-Mebip)dpa were synthesized via N-sulfonylation of di-(2-picolyl)amine in good yield. Their platinum(II) complexes; C1: [PtCl2(N(SO2)(bzd)dpa)], C2: [PtCl2(N(SO2)(4-Mebip)dpa)]·CH3CN were synthesized and characterized by 1H NMR, FTIR, UV–Vis and fluorescence spectroscopies. Structural studies revealed that the L1 and L2 ligands coordinate Pt(II) in a bidentate mode in C1 and C2 complexes, forming an eight-membered chelate ring. Interestingly, L1 possesses two conformations because the dioxan ring exists with a 95:5 occupancy ratio. The L2 ligand crystal undergoes a phase transition to triclinic form with twinning at 90 K whereas, at 150 K, the ligand exists in a monoclinic system; the populations of the two orientations for one pyridine substituent are approximately 78:22. The 1H NMR spectra of both Pt complexes obtained in DMSO‑d6 revealed two doublets (exo-CH2 and endo-CH2) for the magnetically inequivalent methylene protons, in contrast to their uncoordinated ligands, which show a singlet peak for the methylene protons. The NCI-H292 (non-small cell lung cancer cells) and MRC-5 (human normal lung fibroblast cells) were used to examine the in vitro cytotoxic activity of all synthesized compounds. All tested compounds demonstrated notable cytotoxicity against NCI-H292 cells, with the most pronounced cytotoxic effect being displayed by [PtCl2(N(SO2)(4-Mebip)dpa)]·CH3CN (C2). Docking studies strengthen in vivo antiproliferation activity where specific interactions with AKT1, BAX, STK-11, and BCL-2 were explored. Further predictions revealed that the compounds have inhibitory effects on COX-2 and PDE10A proteins.

Terpyridine complexes as superior catalysts for methylene blue dye degradation: Synthesis, characterization, mechanistic insights, kinetic study and recyclability assessment

This manuscript investigates the catalytic potential of terpyridine-based metal complexes (C1–C6) in the efficient degradation of methylene blue dye. The synthesized terpyridine complexes were characterized using various spectroscopic techniques, and their catalytic activity was evaluated in the degradation of methylene blue dye under different experimental conditions. The study reveals that the target complex compounds exhibit notable catalytic efficiency, leading to the effective degradation of the envisioned dye. The reaction kinetics, mechanism, and the influence of various parameters on the catalytic performance were systematically explored. Among different synthesized complexes, Zn-complexes showed better performance than Fe-complexes. Remarkably, the complex C5 showed the best photocatalytic efficiency with a degradation of 79.84 % at optimized conditions of initial dye concentration = 15 mg/L, catalyst dosage = 10 mg, pH = 4, and temperature = 323 K. The recyclability test indicated good stability of the photocatalyst over five cycles with a very small loss of photocatalytic efficiency (∼11.64 %) and the photocatalytic reaction followed pseudo-first order kinetics with a high-rate constant of 0.009 min−1. The trapping experiment revealed the active role of hydroxyl radicals (OH•) and superoxide anions (•O2−) as reactive species on the basis of which a plausible degradation mechanism is proposed. This research contributes valuable insights into the development of terpyridine-based catalysts for the degradation of organic dyes, paving the way for further advancements in the field of catalysis and environmental remediation.

New phthalazine based nickel (II), cobalt (II), and copper (II) mixed-ligand complexes; characterization, physicochemical properties, anti-inflammatory, antifungal, antibacterial, DFT and molecular docking exploration

In this study, we have employed a straightforward and easily synthesized ligand, namely 1,4-dioxo-3,4-dihydrophthalazine-2(1H)-carbothioamide (DDPC), in conjunction with 8-hydroxyquinoline (QOL) to create new mixed-ligand complex compounds such as Co (II) (C1), Ni (II) (C2), and Cu (II) (C3). Recent research has been dedicated to investigating their antibacterial, antifungal, & anti-inflammatory efficacy. Our approach involved the synthesis and characterization of these novel C1, C2, and C3 mixed-ligand complexes using various analytical methods, having elemental analysis, MS, FT-IR, UV spectroscopy, magnetic, TGA, and stoichiometry analysis by molar ratio methods. Octahedral structures were identified for isolated metal complexes. Utilizing density functional theory (DFT), we estimated the quantum chemical characteristics and optimized molecular structures for each compound. To evaluate their effectiveness in inhibiting the proliferation of harmful microorganisms, a disc diffusion test was conducted. The produced complex compounds displayed meaningfully improved antibacterial & antifungal effectiveness in comparison with the free ligands. Additionally, we investigated the anti-inflammatory effects employing the Egg albumin denaturation method. C1, C2, and C3 complexes demonstrated substantial anti-inflammatory potential, surpassing the free ligands & showing analogous efficacy to standard references. Molecular docking analyses against 5JQ9 and 6CLV from Escherichia coli, Staphylococcus aureus, and COX-2 (5IKT) as an anti-inflammatory effectiveness of enzymes confirmed the bioactivity. Among the tested compounds, C3 exhibited the highest binding affinity, suggesting its potential as a building block for the development of new antibiotics. Finally, we correlated the DFT and molecular docking results with in vitro activities and provided a comprehensive discussion.

Design, synthesis and mechanistic studies of novel arylformylhydrazone butylphenyltin complexes as potential anticancer agents

Many diorganotin complexes with various alkyl groups exhibit excellent in vitro anticancer activity. However, most diorganotin is the same alkyl group, and the asymmetric alkyl R group has been rarely reported. Hence, in this paper, twenty butylphenyl mixed dialkyltin arylformylhydrazone complexes have been synthesized by microwave “one-pot” reaction with arylformylhydrazine, substituted α-keto acid or its sodium salt and butylphenyltin dichloride. The crystal structures of nine complexes were determined, indicating that the complexes C1, C2, C11, C12, and C16 ∼ C19 possessed a central symmetric structure of a dinuclear Sn2O2 tetrahedral ring; while the complex C9 is a trinuclear tin-oxygen cluster with a 6-membered ring encased in a 12-membered macrocyclic structure. The inhibiting activity of complexes was tested against the human cell lines NCI-H460, MCF-7, HepG2, Huh-7 and HL-7702. Complex C2 demonstrated the optimal inhibitory effect on HepG2 cells, with an IC50 value of 0.82 ± 0.03 μM. Cellular biology experiments revealed that complex C2 could induce apoptosis and G2/M phase cell cycle arrest in HepG2 and Huh-7 cells. The complex also caused the collapse of the mitochondrial membrane potential and increased intracellular reactive oxygen species in HepG2 and Huh-7 cells. Western blot analysis further clarified that complex C2 could induce cell apoptosis through the mitochondrial pathway along with the release of reactive oxygen species.

New Schiff bases and their vanadium complexes: Synthesis, characterization, and biological assessment for antibacterial and antiviral action

From the perspective of possible antiviral and antibacterial activity of vanadium‐based complexes, we report the synthesis of new Schiff base ligand (L4) and a new Schiff‐base‐vanadium complex (C2). Both the ligand and the complex were characterized by Fourier transform infrared spectroscopy and Nuclear magnetic resonance techniques. Single‐crystal X‐ray Diffraction analysis has been used to confirm the structure of ligand L4 and complex C2. In addition, L1–4 and C1–3 were tested for their antibacterial effects against Escherichia coli and Staphylococcus aureus. Among the compounds, L2 demonstrated the most potent inhibition of both bacteria, exhibiting the lowest values for minimum inhibitory concentration (CMI) and minimum bactericidal concentration (CMB) (CMI = 0.16, CMB = 0.31 against E. coli, and CMI = CMB = 0.16 against S. aureus). Additionally, L2 produced the largest inhibition zones with diameters of 15.5 ± 0.15 against E. coli and 14.5 ± 0.04 against S. aureus. Furthermore, the antiviral efficacy of L1, L2, L4, C1, C2, and C3 against RNA viruses was assessed. C2 and C3 exhibited the most potent antiviral activity among the tested compounds.

Barbituric acid‐derived azo dye metal complexes: Synthesis, characterization, DFT, and antimicrobial analysis

Two novel metal complexes, C1 and C2, were synthesized through the reaction of an azo dye ligand, obtained by coupling 4‐chloroaniline with 1,3‐dimethyl barbituric acid. The structure of the ligand was confirmed using Fourier‐transform infrared spectroscopy (FTIR) and Nuclear magnetic resonance (NMR). UV–Vis spectroscopy was employed to assess the ligand's sensing ability toward six different metal ions. Comprehensive characterization of the synthesized metal complexes was conducted using elemental analysis, X‐ray photoelectron spectroscopy (XPS), thermogravimetric analysis–difference thermogravimetry (TGA‐DTG), FTIR, UV–Vis spectroscopy, electron paramagnetic resonance (EPR) spectroscopy, and single‐crystal X‐ray diffraction (SC‐XRD). X‐ray analysis revealed octahedral coordination geometry with a 2:1 ligand‐to‐metal ratio and dimethylformamide (DMF) coordination with the metal atom in both complexes. Hirshfeld analysis and 2D fingerprint plots were employed to investigate supramolecular and intermolecular interactions within the crystal system. Density functional theory (DFT/B3LYP) calculations were utilized to compute energy gaps and other important theoretical features. Sensing experiments with tetrabutylammonium fluoride (TBAF) were conducted at a concentration of 1 × 10−5 M. Furthermore, the bioactivity of the synthesized metal complexes and ligand L was evaluated through molecular docking studies against Protein Data Bank (PDB IDs) 4XUY (Staphylococcus aureus) and 3BQW (Aspergillus niger). Also, antimicrobial activity was assessed using the agar well diffusion technique, revealing that complexes C1 and C2 exhibited enhanced antimicrobial activities against the tested organisms compared to the parent azo dye ligand. The computational and experimental bioactivity data are in good agreement with each other.

Alkylaluminium complexes supported by Schiff base as pre-catalysts in hydroboration of alkynes and nitriles

Dinuclear Schiff base aluminium complexes (C1, C2) were synthesized from salicylaldehyde derivatives and 2-aminopyridine. Complexes C1 and C2 were characterized by NMR and single-crystal X-ray diffraction. Subsequently, the catalytic activity of C1 as a pre-catalyst for the hydroboration of alkynes and nitriles was investigated. It exhibited good functional group tolerance towards both terminal alkynes and nitriles under solvent-free and low-load conditions. The potential mechanism for the C1-catalyzed reaction of alkynes and nitriles with HBpin are proposed by the NMR spectroscopy of the intermediates.