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Carbon nitrides can form coordination compounds or metallic oxides in the presence of transition metals, depending on the reaction conditions. By adjusting the pH to basic levels for mild synthesis with metals, composites like g-C 3 N 4 -M(OH) x (where M represents metals) were obtained for nickel (II) and manganese (II), while copper (II) yielded coordination compounds such as Cu-g-C 3 N 4 . These materials underwent spectroscopic and electrochemical characterization, revealing their photocatalytic potential to generate superoxide anion radicals-a feature consistent across all metals. Notably, the copper coordination compound also produced significant hydroxyl radicals. Leveraging this catalytic advantage, with band gap energy in the visible region, all compounds were activated to disinfect E. coli bacteria, achieving total disinfection with Cu-g-C 3 N 4 . The textural properties influence the catalytic performance, with copper's stabilization as a coordination compound enabling more efficient activity compared to the other metals. Additionally, the determination of radicals generated under light in the presence of dicloxacillin supported the proposed mechanism and highlighted the potential for degrading organic molecules with this new material, alongside its disinfectant properties.

Copper complexes have shown promising anticancer properties, but they are often poorly soluble in aqueous solutions, thus limiting their possible medical developments and applications. We have recently isolated some copper(II) complexes with salicylaldehyde thiosemicarbazone ligands exhibiting remarkable nanomolar cytotoxic activity, but in vivo tests evidenced several difficulties related to their poor solubility. To overcome these limitations and increase solubility in aqueous solution, herein we report the synthetic strategy that led to the introduction of the sulfonic group on the ligands, then separated as salts (NaH 2 L 1 - NaH 2 L 5 ), as well as the synthesis and characterization of the related copper(II) complexes. The characterization of the complexes is completed by the analysis of the structures obtained by X-rays diffraction on single crystals on the species [Cu(HL 5 )(H 2 O)] 2 . 2H 2 O, [Cu(HL 2 )(H 2 O) 2 ] . 2H 2 O, and [Cu(HL 1 )(H 2 O] 2 . 2H 2 O. While the uncoordinated ligands do not affect cancer cell viability, copper(II) complexes exhibit low to sub-micromolar cytotoxic activity, which is maintained in 3D (HCT-15 and 2008) spheroidal models of cancer cell. Notably, copper(II) complexes were selective towards cancer cells, showing high selectivity indexes. Investigations focused on elucidating the mechanism of action evidenced the protein disulfide-isomerase as an innovative molecular target for this class of water-soluble copper(II) complexes. Finally, preliminary in vivo experiments performed with the most representative derivative in the murine Lewis Lung Carcinoma, highlight its significant antitumor efficacy and better tolerability profile with respect to the reference metallodrug, suggesting for this sulfonated Cu(II) complex a potential clinical relevance., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 The Authors. Published by Elsevier Masson SAS.. All rights reserved.)

A new photoactive cobalt coordination compound, [Co(NH 3 ) 5 NO 2 ]BrNO 3 (I), was obtained. Its crystal structure was shown to be isostructural with previously known [Co(NH 3 ) 5 NO 2 ]ClNO 3 (II) for which linkage isomerization accompanied with mechanical response of the crystal has been already reported. Single crystals of I are transformed into nitrito isomer [Co(NH 3 ) 5 ONO]BrNO 3 (III) on irradiation with blue light (λ = 465 nm) without being destroyed. The crystal structure of III was also solved using single-crystal X-ray diffraction and compared with previously known [Co(NH 3 ) 5 ONO]ClNO 3 (IV). A detailed comparison of the structures of I, II, III and IV, including unit-cell parameters, the distribution of free space (in particular, reaction cavities around the nitro ligand), the lengths of hydrogen bonds, coordination and Voronoi-Dirichlet polyhedra has been performed. Single-crystal X-ray diffraction data were complemented with IR spectra. The effect of the replacement of Cl - by Br - on the crystal structure and on the nitro-nitrito photoisomerization is discussed.

Two new lanthanide-complexes based on the 5-nitropicolinate ligand (5-npic) were obtained and fully characterized. Single-crystal X-ray diffraction revealed that these compounds are isostructural to a Dy-complex, previously published by us, based on dinuclear monomers link together with an extended hydrogen bond network, providing a final chemical formula of [Ln 2 (5-npic) 6 (H 2 O) 4 ]·(H 2 O) 2 , where Ln = Dy (1), Gd (2), and Tb (3). Preliminary photoluminescent studies exhibited a ligand-centered emission for all complexes. The potential antitumoral activity of these materials was assayed in a prostatic cancer cell line (PC-3; the 2nd most common male cancerous disease), showing a significant anticancer activity (50-60% at 500 μg·mL -1 ). In turn, a high biocompatibility by both, the complexes and their precursors in human immunological HL-60 cells, was evidenced. In view of the strongest toxic effect in the tumoral cell line provided by the free 5-npic ligand (~ 40-50%), the overall anticancer complex performance seems to be triggered by the presence of this molecule., (© 2024. The Author(s).)

Candida spp. are the commonest fungal pathogens worldwide. Antifungal resistance is a problem that has prompted the discovery of novel anti-Candida drugs. Herein, 25 compounds, some of them containing copper(II), cobalt(II) and manganese(II) ions, were initially evaluated for inhibiting the growth of reference strains of Candida albicans and Candida tropicalis. Eight (32%) of the compounds inhibited the proliferation of these yeasts, displaying minimum inhibitory concentrations (MICs) ranging from 31.25 to 250 μg/mL and minimum fungicidal concentration (MFCs) from 62.5 to 250 μg/mL. Drug-likeness/pharmacokinetic calculated by SwissADME indicated that the 8 selected compounds were suitable for use as topical drugs. The complex CTP, Cu(theo) 2 phen(H 2 O).5H 2 O (theo = theophylline; phen = 1,10-phenanthroline), was chosen for further testing against 10 medically relevant Candida species that were resistant to fluconazole/amphotericin B. CTP demonstrated a broad spectrum of action, inhibiting the growth of all 20 clinical fungal isolates, with MICs from 7.81 to 62.5 μg/mL and MFCs from 15.62 to 62.5 μg/mL. Conversely, CTP did not cause lysis in erythrocytes. The toxicity of CTP was evaluated in vivo using Galleria mellonella and Tenebrio molitor. CTP had no or low levels of toxicity at doses ranging from 31.25 to 250 μg/mL for 5 days. After 24 h of treatment, G. mellonella larvae exhibited high survival rates even when exposed to high doses of CTP (600 μg/mL), with the 50% cytotoxic concentration calculated as 776.2 μg/mL, generating selectivity indexes varying from 12.4 to 99.4 depending on each Candida species. These findings suggest that CTP could serve as a potential drug to treat infections caused by Candida species resistant to clinically available antifungals., (© 2023. The Author(s), under exclusive licence to Springer Nature B.V.)

Background: New chemotherapeutics are urgently required to treat Candida infections caused by drug-resistant strains. Methods: The effects of 16 1,10-phenanthroline (phen)/1,10-phenanthroline-5,6-dione/dicarboxylate complexed with Mn(II), Cu(II) and Ag(I) were evaluated against ten different Candida species. Results: Proliferation of Candida albicans , Candida dubliniensis , Candida famata , Candida glabrata , Candida guilliermondii , Candida kefyr , Candida krusei , Candida lusitaniae , Candida parapsilosis and Candida tropicalis was inhibited by three of six Cu(II) (MICs 1.52-21.55 μM), three of three Ag(I) (MICs 0.11-12.74 μM) and seven of seven Mn(II) (MICs 0.40-38.06 μM) complexes. Among these [Mn 2 (oda)(phen) 4 (H 2 O) 2 ][Mn 2 (oda)(phen) 4 (oda) 2 ].4H 2 O, where oda = octanedioic acid, exhibited effective growth inhibition (MICs 0.4-3.25 μM), favorable activity indexes, low toxicity against Vero cells and good/excellent selectivity indexes (46.88-375). Conclusion: [Mn 2 (oda)(phen) 4 (H 2 O) 2 ][Mn 2 (oda)(phen) 4 (oda) 2 ].4H 2 O represents a promising chemotherapeutic option for emerging, medically relevant and drug-resistant Candida species.

Most diseases that affect human beings across the world are now treated with drugs of organic origin. However, some of these are associated with side effects, toxicity, and resistance phenomena. For the treatment of many illnesses, the development of new molecules with pharmacological potential is now an urgent matter. The biological activities of metal complexes have been reported to have antitumor, antimicrobial, anti-inflammatory, anti-infective and antiparasitic effects, amongst others. Metal complexes are effective because they possess unique properties. For example, the complex entity possesses the effective biological activity, then the formation of coordination bonds between the metal ions and ligands is controlled, metal ions provide it with extraordinary mechanisms of action because of characteristics such as d-orbitals, oxidation states, and specific orientations; metal complexes also exhibit good stability and good physicochemical properties such as water solubility. Platinum is a transition metal widely used in the design of drugs with antineoplastic activities; however, platinum is associated with side effects which have made it necessary to search for, and design, novel complexes based on other metals. Copper is a biometal which is found in living systems; it is now used in the design of metal complexes with biological activities that have demonstrated antitumoral, antimicrobial and anti-inflammatory effects, amongst others. In this review, we consider the open horizons of Cu(II)- and Pt(II)-based complexes, new trends in their design, their synthesis, their biological activities and their targets of action.

Redox non-innocent ligands react with metal precursors to form complexes where the oxidation states of the ligand and thus the metal atom cannot be easily defined. A well-known example of such ligands is bis( o -aminophenol) N , N '-bis(3,5-di- tert butyl-2-hydroxy-phenyl)-1,2-phenylenediamine, previously developed by the Wieghardt group, which has a potentially tetradentate coordination mode and four distinct protonation states, whereas its electrochemical behavior allows for five distinct oxidation states. This rich redox chemistry, as well as the ability to coordinate to various transition metals, has been utilized in the syntheses of metal complexes with M 2 L, ML and ML 2 stoichiometries, sometimes supported with other ligands. Different oxidation states of the ligand can adopt different coordination modes. For example, in the fully oxidized form, two N donors are sp 2 -hybridized, which makes the ligand planar, whereas in the fully reduced form, the sp 3 -hybridized N donors allow the formation of more flexible chelate structures. In general, the metal can be reduced during complexation, but redox processes of the isolated complexes typically occur on the ligand. Combination of this non-innocent ligand with redox-active transition metals may lead to complexes with interesting magnetic, electrochemical, photonic and catalytic properties.

Coumarin (2H-1-benzopyran-2-one) presents the fundamental structure of an enormous class of biologically active compounds of natural, semi-synthetic, and synthetic origin. Extensive efforts are continually being put into the research and development of coumarin derivatives with medicinal properties by the broad scientific community. Transition metal coordination compounds with potential biological activity are a "hot topic" in the modern search for novel drugs. Complexation with transition metals can enhance the physiological effect of a molecule, modify its safety profile, and even imbue it with novel attributes of interest in the fields of medicine and pharmacy. The present review aims to inform the reader of the latest developments in the search for coumarin transition metal complexes with biological activity, their potential applications, and structure-activity relationships, where such can be elucidated. Each section of the present review addresses a certain kind of biological activity (antiproliferative, antioxidant, antimicrobial, etc.), explores the most recent discoveries in the field, and, at the same time, tries to offer useful perspectives for potential future investigations., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2024 Todorov and Kostova.)

As an inherent metal ion, copper has been the subject of investigation for developing a novel antitumoral compound that exhibits fewer adverse effects. Copper serves as a cofactor in multiple enzymes, generates reactive oxygen species (ROS), facilitates tumour evolution, metastasis and angiogenesis and has been detected at elevated concentrations in the serum and tissues of various human cancer types. In the given setting, utilising two methodologies in developing novel Copper-based pharmaceuticals for anti-cancer applications is standard practice. These approaches involve either the sequestration of unbound Copper ions or the synthesis of Copper complexes that induce cellular apoptosis. In the past four decades, the latter system has been used, leading to numerous reviews that have examined the anticancer characteristics of a wide range of Copper complexes. These analyses have consistently demonstrated that multiple factors frequently influence the efficacy of these compounds. This review examines the possible anticancer properties of copper and Cu(II) complexes that incorporate Schiff base ligands containing 1,10-phenanthroline. The present study will comprehensively analyse the examined cell lines and mechanistic research associated with each complex., Competing Interests: Declaration of Competing Interest The authors assert that they do not possess any identifiable conflicting financial interests or personal affiliations that could have potentially influenced the research findings presented in this study., (Copyright © 2023 Elsevier Inc. All rights reserved.)

Tetrahedral copper(II) and zinc(II) coordination compounds from 5-nitroimidazole derivatives, viz. 1-(2-chloroethyl)-2-methyl-5-nitroimidazole (cenz) and ornidazole 1-(3-chloro-2-hydroxypropyl)-2-methyl-5-nitroimidazole (onz), were synthesized and spectroscopically characterized. Their molecular structures were determined by X-ray diffraction studies. The complexes [Cu(onz) 2 X 2 ], [Zn(onz) 2 X 2 ], [Cu(cenz) 2 X 2 ] and [Zn(cenz) 2 X 2 ] (X -  = Cl, Br), are stable in solution and exhibit positive LogD 7.4 values that are in the range for molecules capable of crossing the cell membrane via passive difussion. Their biological activity against Toxoplasma gondi was investigated, and IC 50 and lethal dose (LD 50 ) values were determined. The ornidazole copper(II) compounds showed very good antiparasitic activity in its tachyzoite morphology. The interaction of the coordination compounds with DNA was examined by circular dichroism, fluorescence (using intercalating ethidium bromide and minor groove binding Hoechst 33258) and UV-Vis spectroscopy. The copper(II) compounds interact with the minor groove of the biomolecule, whereas weaker electrostatic interactions take place with the zinc(II) compounds. The spectroscopic data achieved for the two series of complexes (namely with copper(II) and zinc(II) as metal center) agree with the respective DNA-damage features observed by gel electrophoresis., (© 2023. The Author(s).)

Reactive oxygen species (ROS) are closely related to oxidative stress, aging, and the onset of human diseases. To mitigate ROS-induced damages, extensive research has focused on examining the antioxidative attributes of various synthetic/natural substances. Coordination compounds serving as synthetic antioxidants have emerged as a promising approach to attenuate ROS toxicity. Herein, we investigated the antioxidant potential of a series of Fe(III) (1), Mn(III)Mn(II) (2) and Cu(II) (3) coordination compounds synthesized with the ligand N-(2-hydroxybenzyl)-N-(2-pyridylmethyl)[(3-chloro)(2-hydroxy)]-propylamine in Saccharomyces cerevisiae exposed to oxidative stress. We also assessed the antioxidant potential of these complexes in the alternative model of study, Galleria mellonella. DPPH analysis indicated that these complexes presented moderate antioxidant activity. However, treating Saccharomyces cerevisiae with 1, 2 and 3 increased the tolerance against oxidative stress and extended yeast lifespan. The treatment of yeast cells with these complexes decreased lipid peroxidation and catalase activity in stressed cells, whilst no change in SOD activity was observed. Moreover, these complexes induced the Hsp104 expression. In G. mellonella, complex administration extended larval survival under H2O2 stress and did not affect the insect's life cycle. Our results suggest that the antioxidant potential exhibited by these complexes could be further explored to mitigate various oxidative stress-related disorders., (© The Author(s) 2023. Published by Oxford University Press on behalf of FEMS.)

Seed-mediated growth has been widely used to synthesize noble metal nanoparticles with controlled size and shape. Although it is becoming possible to directly observe the nucleation process of metal atoms at the single atom level by using transmission electron microscopy (TEM), it is challenging to control the formation and growth of seeds with only a few metal atoms in homogeneous solution systems. This work reports site-selective formation and growth of atomic scale seeds of the Au nanoparticle in a nanospace of an organic cage molecule. We synthesized a cage molecule with amines and phenols, which were found to both capture and reduce Au(III) ions to spontaneously form the atomic scale seeds containing Au(0) in the nanospace. The growth reaction of the atomic scale seeds afforded Au nanoparticles with an average diameter of 2.0±0.2 nm, which is in good agreement with the inner diameter of the cage molecule., (© 2023 Wiley-VCH GmbH.)

A skin wound is prone to bacterial infection and growth. An antibacterial topical hydrogel that can act as a self-drug-delivery (SDD) system is reported here. Two bidentate ligands ( L2/L1 ) derived from imidazole/benzimidazole derivatives when reacted with Zn(NO 3 ) 2 and a series of nonsteroidal-anti-inflammatory drugs (NSAIDs) produced crystalline products, which were characterized by single-crystal X-ray diffraction (SXRD). Simple mixing of the ingredients of the crystalline products (stoichiometry guided by the corresponding crystal structure) produced an aqueous gel (DMSO/water) when the bidentate ligand was water-insoluble L2 , whereas water-soluble L1 readily produced hydrogels under similar conditions. Dynamic rheology and scanning electron microscopy (SEM) were employed to characterize the gels. Zone inhibition diameters, minimum inhibitory concentration (MIC), minimum bactericidal concentration (MBC), and hemolysis data suggested that among the hydrogelators, L1MEC derived from L1 , meclofenac and Zn(NO 3 ) 2 , was found to be the best against the Gram-negative bacteria Escherichia coli . The corresponding hydrogel L1MEC_HG and a piece of a dried cloth bandage coated with the hydrogel also showed appreciable activity against E. coli . The antibacterial property of L1MEC_HG against E. coli , thus demonstrated, is relevant in developing an antibacterial SDD system because E. coli is reported to be present in infected wounds.

Constructing multifunctional interphases to suppress the rampant Zn dendrite growth and detrimental side reactions is crucial for Zn anodes. Herein, a phytic acid (PA)-ZnAl coordination compound is demonstrated as a versatile interphase layer to stabilize Zn anodes. The zincophilic PA-ZnAl layer can manipulate Zn 2+ flux and promote rapid desolvation kinetics, ensuring the uniform Zn deposition with dendrite-free morphology. Moreover, the robust PA-ZnAl protective layer can effectively inhibit the hydrogen evolution reaction and formation of byproducts, further contributing to the reversible Zn plating/stripping with high Coulombic efficiency. As a result, the Zn@PA-ZnAl electrode shows a lower Zn nucleation overpotential and higher Zn 2+ transference number compared with bare Zn. The Zn@PA-ZnAl symmetric cell exhibits a prolonged lifespan of 650 h tested at 5 mA cm -2 and 5 mAh cm -2 . Furthermore, the assembled Zn battery full cell based on this Zn@PA-ZnAl anode also delivers decent cycling stability even under harsh conditions., (© 2023 Wiley-VCH GmbH.)

Background: Scedosporium/Lomentospora species are human pathogens that are resistant to almost all antifungals currently available in clinical practice. Methods: The effects of 16 1,10-phenanthroline (phen)/1,10-phenanthroline-5,6-dione/dicarboxylate chelates containing Cu(II), Mn(II) and Ag(I) against Scedosporium apiospermum , Scedosporium minutisporum , Scedosporium aurantiacum and Lomentospora prolificans were evaluated. Results: To different degrees, all of the test chelates inhibited the viability of planktonic conidial cells, displaying MICs ranging from 0.029 to 72.08 μM. Generally, Mn(II)-containing chelates were the least toxic to lung epithelial cells, particularly [Mn 2 (oda)(phen) 4 (H 2 O) 2 ][Mn 2 (oda)(phen) 4 (oda) 2 ].4H 2 O (MICs: 1.62-3.25 μM: selectivity indexes >64). Moreover, this manganese-based chelate reduced the biofilm biomass formation and diminished the mature biofilm viability. Conclusion: [Mn 2 (oda)(phen) 4 (H 2 O) 2 ][Mn 2 (oda)(phen) 4 (oda) 2 ].4H 2 O opens a new chemotherapeutic avenue for the deactivation of these emergent, multidrug-resistant filamentous fungi.

The therapeutic advantages of some platinum complexes as major anticancer chemotherapeutic agents and of nucleoside analogue-based compounds as essential antiviral/antitumor drugs are widely recognized. Red blood cells (RBCs) offer a potential new strategy for the targeted release of therapeutic agents due to their biocompatibility, which can protect loaded drugs from inactivation in the blood, thus improving biodistribution. In this study, we evaluated the feasibility of loading model nucleobase-containing Pt(II) complexes into human RBCs that were highly stabilized by four N -donors and susceptible to further modification for possible antitumor/antiviral applications. Specifically, platinum-based nucleoside derivatives [Pt II (dien)( N7 -Guo)] 2+ , [Pt II (dien)( N7 -dGuo)] 2+ , and [Pt II (dien)( N7 -dGTP)] (dien = diethylenetriamine; Guo = guanosine; dGuo = 2'-deoxy-guanosine; dGTP = 5'-(2'-deoxy)-guanosine-triphosphate) were investigated. These Pt(II) complexes were demonstrated to be stable species suitable for incorporation into RBCs. This result opens avenues for the possible incorporation of other metalated nucleobases analogues, with potential antitumor and/or antiviral activity, into RBCs.

This study focuses on developing and evaluating two novel enantioselective biomimetic models for the active centers of oxidases (ascorbate oxidase and catalase). These models aim to serve as alternatives to enzymes, which often have limited action and a delicate nature. For the ascorbate oxidase (AO) model (compound 1 ), two enantiomers, S,S(+)cpse and R,R(-)cpse, were combined in a crystalline structure, resulting in a racemic compound. The analysis of their magnetic properties and electrochemical behavior revealed electronic transfer between six metal centers. Compound 1 effectively catalyzed the oxidation of ascorbic to dehydroascorbic acid, showing a 45.5% yield for the racemic form. This was notably higher than the enantiopure compounds synthesized previously and tested in the current report, which exhibited yields of 32% and 28% for the S,S(+)cpse and R,R(-)cpse enantiomers, respectively. This outcome highlights the influence of electronic interactions between metal ions in the racemic compound compared to pure enantiomers. On the other hand, for the catalase model (compound 2 ), both the compound and its enantiomer displayed polymeric properties and dimeric behavior in the solid and solution states, respectively. Compound 2 proved to be effective in catalyzing the oxidation of hydrogen peroxide to oxygen with a yield of 64.7%. In contrast, its enantiomer (with R,R(-)cpse) achieved only a 27% yield. This further validates the functional nature of the prepared biomimetic models for oxidases. This research underscores the importance of understanding and designing biomimetic models of metalloenzyme active centers for both biological and industrial applications. These models show promising potential as viable alternatives to natural enzymes in various processes.

Molecular properties of coordination compounds can be efficiently studied by vibrational spectroscopy. The scope of Raman spectroscopy has been greatly enhanced by the introduction of Raman optical activity (ROA) sensitive to chirality. The present review describes some of its recent applications to study the coordination compounds. 3d and 4f metal complexes often absorb the excitation light, or exhibit luminescence. Therefore, effects caused in ROA spectra by electronic circular dichroism (ECD) and circularly polarized luminescence (CPL) must be taken into consideration.In 3d metal complexes ECD and circularly-polarized Raman scattering compete with the resonance ROA (RROA) signal. Pure RROA spectrum can thus be obtained by subtracting the so-called ECD-Raman component. CPL is frequently encountered in 4f systems. While it can mask the ROA spectra, it is useful to study molecular structure. These electronic effects can be reduced by using near-infrared excitation although vibrational ROA signal is much weaker compared to the usual green laser excitation scenario. The ROA methodology is thus complex, but capable of providing unique information about the molecules of interests and their interaction with light., (© 2023 The Authors. ChemPlusChem published by Wiley-VCH GmbH.)

New coordination compounds of copper(II) with 2,5-bis(ethylthio)-1,3,4-thiadiazole (L 1 ) and 2,5-bis(pyridylmethylthio)-1,3,4-thiadiazole (L 2 ) with compositions Cu(L 1 ) 2 Br 2 , Cu(L 1 )(C 2 N 3 ) 2 , Cu(L 2 )Cl 2 , and Cu(L 2 )Br 2 were prepared. The complexes were identified and studied by CHN analysis, infrared (IR) spectroscopy, powder X-Ray diffraction (XRD), and static magnetic susceptibility. The crystal structures of Cu(II) complexes with L 1 were determined. The structures of the coordination core of complexes Cu(L 2 )Cl 2 and Cu(L 2 )Br 2 were determined by Extended X-ray absorption fine structure (EXAFS) spectroscopy. Magnetization measurements have revealed various magnetic states in the studied complexes, ranging from an almost ideal paramagnet in Cu(L 1 ) 2 Br 2 to alternating-exchange antiferromagnetic chains in Cu(L 1 )(C 2 N 3 ) 2 , where double dicyanamide bridges provide an unusually strong exchange interaction (J 1 /k B ≈ -23.5 K; J 2 /k B ≈ -20.2 K) between Cu(II) ions. The cytotoxic activity of copper(II) complexes with L 2 was estimated on the human cell lines of breast adenocarcinoma ( MCF-7 ) and hepatocellular carcinoma ( HepG2 ).

Six new complexes of the ligand HQ cy (-4-(cyclohexanecarbonyl)-5-methyl-2-phenyl-2,4-dihydro-3H-pyrazol-3-one) and Ln 3+ ions with emission in the near-infrared (Nd 3+ ) or visible and near-infrared (Sm 3+ , Pr 3+ ) spectral regions were synthesized and characterized using various methods, including single crystal X-ray diffraction. The study demonstrated that both tris complexes [LnQ cy 3 (H 2 O)(EtOH)] and tetrakis-acids [H 3 O][LnQ cy 4 complex by up to 2 times. The results obtained from this study provide insights into the luminescent properties of lanthanide coordination compounds, which are crucial for the design and development of novel photonic materials with tailored photophysical properties.3+ complex, and increased the quantum yield of the Sm 3+ complex by up to 2 times. The results obtained from this study provide insights into the luminescent properties of lanthanide coordination compounds, which are crucial for the design and development of novel photonic materials with tailored photophysical properties.

Leishmaniasis, caused by protozoa of the genus Leishmania , encompasses a group of neglected diseases with diverse clinical and epidemiological manifestations that can be fatal if not adequately and promptly managed/treated. The current chemotherapy options for this disease are expensive, require invasive administration and often lead to severe side effects. In this regard, our research group has previously reported the potent anti- Leishmania activity of two coordination compounds (complexes) derived from 1,10-phenanthroline-5,6-dione (phendione): [Cu(phendione) 3 ].(ClO 4 ) 2 .4H 2 O and [Ag(phendione) 2 ].ClO 4 . The present study aimed to evaluate the effects of these complexes on leishmanolysin (gp63), a virulence factor produced by all Leishmania species that plays multiple functions and is recognized as a potential target for antiparasitic drugs. The results showed that both Ag-phendione (-74.82 kcal/mol) and Cu-phendione (-68.16 kcal/mol) were capable of interacting with the amino acids comprising the active site of the gp63 protein, exhibiting more favorable interaction energies compared to phendione alone (-39.75 kcal/mol) or 1,10-phenanthroline (-45.83 kcal/mol; a classical gp63 inhibitor) as judged by molecular docking assay. The analysis of kinetic parameters using the fluorogenic substrate Z-Phe-Arg-AMC indicated V max and apparent K m values of 0.064 µM/s and 14.18 µM, respectively, for the released gp63. The effects of both complexes on gp63 proteolytic activity were consistent with the in silico assay, where Ag-phendione exhibited the highest gp63 inhibition capacity against gp63, with an IC 50 value of 2.16 µM and the lowest inhibitory constant value (K i = 5.13 µM), followed by Cu-phendione (IC 50 = 163 µM and K i = 27.05 µM). Notably, pretreatment of live L. amazonensis promastigotes with the complexes resulted in a significant reduction in the expression of gp63 protein, including the isoforms located on the parasite cell surface. Both complexes markedly decreased the in vitro association indexes between L. amazonensis promastigotes and THP-1 human macrophages; however, this effect was reversed by the addition of soluble gp63 molecules to the interaction medium. Collectively, our findings highlight the potential use of these potent complexes in antivirulence therapy against Leishmania , offering new insights for the development of effective treatments for leishmaniasis.

This paper describes the synthesis and characterization of seven different copper(II) coordination compounds, as well as the formation of a protonated ligand involving all compounds from the same reaction. Their synthesis required hydrothermal conditions, causing the partial in situ transformation of 5-fluoro uracil-1-acetic acid (5-FUA) into an oxalate ion (ox), as well as the protonation of the 4,4'-bipyridine (bipy) ligand through a catalytic process resulting from the presence of Cu(II) within the reaction. These initial conditions allowed obtaining the new coordination compounds [Cu 2 (5-FUA) 2 (ox)(bipy)] n ·2n H 2 O (CP2) , [Cu(5-FUA) 2 (H 2 O)(bipy)] n ·2n H 2 O (CP3) , as well as the ionic pair [(H 2 bipy) +2 2NO 3 - ] (1) . The mother liquor evolved rapidly at room temperature and atmospheric pressure, due to the change in concentration of the initial reagents and the presence of the new chemical species generated in the reaction process, yielding CPs [Cu(5-FUA) 2 (bipy)] n ·3.5n H 2 O , [Cu 3 (ox) 3 (bipy) 4 ] n and [Cu(ox)(bipy)] n . The molecular compound [Cu(5-FUA) 2 (H 2 O) 4 ]·4H 2 O (more thermodynamically stable) ended up in the mother liquor after filtration at longer reaction times at 25 °C and 1 atm., cohabiting in the medium with the other crystalline solids in different proportions. In addition, the evaporation of H 2 O caused the single-crystal to single-crystal transformation (SCSC) of [Cu(5-FUA) 2 (H 2 O)(bipy)] n ·2n H 2 O (CP3) into [Cu(5-FUA) 2 (bipy)] n ·2n H 2 O (CP4) . A theoretical study was performed to analyze the thermodynamic stability of the phases. The observed SCSC transformation also involved a perceptible color change, highlighting this compound as a possible water sensor., Competing Interests: The authors declare no conflicts of interest.

In this work, we elucidated some key aspects of the mechanism of action of the cisplatin anticancer drug, cis -[Pt(NH 3 ) 2 Cl 2 ], involving direct interactions with free nucleotides. A comprehensive in silico molecular modeling analysis was conducted to compare the interactions of Thermus aquaticus (Taq) DNA polymerase with three distinct N7 -platinated deoxyguanosine triphosphates: [Pt(dien)( N7 -dGTP)] ( 1 ), cis -[Pt(NH 3 ) 2 Cl( N7 -dGTP)] ( 2 ), and cis -[Pt(NH 3 ) 2 (H 2 O)( N7 -dGTP)] ( 3 ) {dien = diethylenetriamine; dGTP = 5'-(2'-deoxy)-guanosine-triphosphate}, using canonical dGTP as a reference, in the presence of DNA. The goal was to elucidate the binding site interactions between Taq DNA polymerase and the tested nucleotide derivatives, providing valuable atomistic insights. Unbiased molecular dynamics simulations (200 ns for each complex) with explicit water molecules were performed on the four ternary complexes, yielding significant findings that contribute to a better understanding of experimental results. The molecular modeling highlighted the crucial role of a specific α-helix (O-helix) within the fingers subdomain, which facilitates the proper geometry for functional contacts between the incoming nucleotide and the DNA template needed for incorporation into the polymerase. The analysis revealed that complex 1 exhibits a much lower affinity for Taq DNA polymerase than complexes 2 - 3 . The affinities of cisplatin metabolites 2 - 3 for Taq DNA polymerase were found to be quite similar to those of natural dGTP, resulting in a lower incorporation rate for complex 1 compared to complexes 2 - 3 . These findings could have significant implications for the cisplatin mechanism of action, as the high intracellular availability of free nucleobases might promote the competitive incorporation of platinated nucleotides over direct cisplatin attachment to DNA. The study's insights into the incorporation of platinated nucleotides into the Taq DNA polymerase active site suggest that the role of platinated nucleotides in the cisplatin mechanism of action may have been previously underestimated.

Owing to the environmental problems of numerous metal production processes, there is a growing need for more energy-efficient approaches. Cobalt is considered a strategic element that is extracted not only from ores but also from spent Li-ion batteries. One promising new approach is ionometallurgy, which is the extraction of metal oxides by ionic liquids (ILs). This study concerns new investigations into ionometallurgical processing of CoO, Co 3 O 4 , and LiCoO 2 in the IL betainium bis(trifluoromethylsulfonyl)imide, [Hbet][NTf 2 ]. Three crystal structures of cobalt-betaine complex compounds and combined spectroscopic and diffraction studies provide insights into the dissolution process. In addition, an optimized dissolution procedure for metal oxides is presented, avoiding the previously reported decomposition of the IL. Subsequent cobalt electrodeposition is only possible from cationic complex species, highlighting the importance of a thorough understanding of the complex equilibria. The presented method is also compared to other recently reported approaches., (© 2023 The Authors. ChemSusChem published by Wiley-VCH GmbH.)

Complexes emitting in the blue spectral region are attractive materials for developing white-colored light sources. Here, we report the luminescence properties of novel coordination compounds based on the trivalent group 3, 13 metals, and the 1-phenyl-3-methyl-4-cyclohexylcarbonyl-pyrazol-5-onate (Q CH ) ligand. [M(Q CH ) 3 ] (M = Al, Ga, and In), [M(Q CH ) 3 (H 2 O)] (M = Sc, Gd, and Lu), [Lu(Q CH ) 3 (DMSO)], and [La(Q CH ) 3 (H 2 O)(EtOH)] complexes were synthesized and structurally characterized by a single-crystal X-ray diffraction study. It has been found that the luminescence quantum yields of the ligand increase by one order of magnitude upon metal coordination. A significant correspondence between the energies of the ligand's excited states and the luminescence quantum yields to the metal ion's atomic numbers was found using molecular spectroscopy techniques. The replacement of the central ion with the heavier one leads to a monotonic increase in singlet state energy, while the energy of the triplet state is similar for all the complexes. Time-resolved measurements allowed us to estimate the intersystem crossing (ISC) rate constants. It was shown that replacing the Al 3+ ion with the heavier diamagnetic Ga 3+ and In 3+ ions decreased the ISC rate, while the replacement with the paramagnetic Gd 3+ ion increased the ISC rate, which resulted in a remarkably bright and room-temperature phosphorescence of [Gd(Q CH ) 3 (H 2 O)].

Ubiquitously present in plant life, coumarins, as a class of phenolic compounds, have multiple applications-in everyday life, in organic synthesis, in medicine and many others. Coumarins are well known for their broad spectrum of physiological effects. The specific structure of the coumarin scaffold involves a conjugated system with excellent charge and electron transport properties. The antioxidant activity of natural coumarins has been a subject of intense study for at least two decades. Significant research into the antioxidant behavior of natural/semi-synthetic coumarins and their complexes has been carried out and published in scientific literature. The authors of this review have noted that, during the past five years, research efforts seem to have been focused on the synthesis and examination of synthetic coumarin derivatives with the aim to produce potential drugs with enhanced, modified or entirely novel effects. As many pathologies are associated with oxidative stress, coumarin-based compounds could be excellent candidates for novel medicinal molecules. The present review aims to inform the reader on some prominent results from investigations into the antioxidant properties of novel coumarin compounds over the past five years.

Inverted perovskite solar cells with a p-i-n configuration have attracted considerable attention from the research community because of their simple design, insignificant hysteresis, improved operational stability, and low-temperature fabrication technology. However, this type of device is still lagging behind the classical n-i-p perovskite solar cells in terms of its power conversion efficiency. The performance of p-i-n perovskite solar cells can be increased using appropriate charge transport and buffer interlayers inserted between the main electron transport layer and top metal electrode. In this study, we addressed this challenge by designing a series of tin and germanium coordination complexes with redox-active ligands as promising interlayers for perovskite solar cells. The obtained compounds were characterized by X-ray single-crystal diffraction and/or NMR spectroscopy, and their optical and electrochemical properties were thoroughly studied. The efficiency of perovskite solar cells was improved from a reference value of 16.4% to 18.0-18.6%, using optimized interlayers of the tin complexes with salicylimine (1) or 2,3-dihydroxynaphthalene (2) ligands, and the germanium complex with the 2,3-dihydroxyphenazine ligand (4). The IR s-SNOM mapping revealed that the best-performing interlayers form uniform and pinhole-free coatings atop the PC 61 BM electron-transport layer, which improves the charge extraction to the top metal electrode. The obtained results feature the potential of using tin and germanium complexes as prospective materials for improving the performance of perovskite solar cells.

Bioleaching is considered an alternative to traditional rare earth extraction technology. However, since rare earth elements exist as complexes in bioleaching lixivium, they cannot be directly precipitated by normal precipitants, which restricts their further development. This structurally stable complex is also a common challenge in various types of industrial wastewater treatment. In this work, a new method called a three-step precipitation process is first proposed to efficiently recover rare earth-citrate (RE-Cit) complexes from (bio)leaching lixivium. It consists of coordinate bond activation (carboxylation by pH adjustment), structure transformation (Ca 2+ addition) and carbonate precipitation (soluble CO 3 2- addition). The optimization conditions are determined to adjust the lixivium pH to around 2.0, then add calcium carbonate until the n(Ca 2+ ): n(Cit 3- ) is more than 1.4:1 and lastly add sodium carbonate until n(CO 3 2- ): n(RE 3+ ) is more than 4:1. The results of precipitation experiments using imitated lixivium show that the rare earth yield is more than 96% and the impurity aluminum yield is less than 20%. Subsequently, pilot tests (1000 L) using real lixivium were successfully conducted. The precipitation mechanism is briefly discussed and proposed by thermogravimetric analysis, Fourier infrared spectroscopy, Raman spectroscopy and UV spectroscopy. This technology is promising in the industrial application of rare earth (bio)hydrometallurgy and wastewater treatment due to its advantages of high efficiency, low cost, environmental friendliness and simple operation., Competing Interests: Declaration of Competing Interest All authors declare that No conflict of interest exists., (Copyright © 2023 Elsevier Ltd. All rights reserved.)

Nucleoside analogues (NAs) are a family of compounds which include a variety of purine and pyrimidine derivatives, widely used as anticancer and antiviral agents. For their ability to compete with physiological nucleosides, NAs act as antimetabolites exerting their activity by interfering with the synthesis of nucleic acids. Much progress in the comprehension of their molecular mechanisms has been made, including providing new strategies for potentiating anticancer/antiviral activity. Among these strategies, new platinum-NAs showing a good potential to improve the therapeutic indices of NAs have been synthesized and studied. This short review aims to describe the properties and future perspectives of platinum-NAs, proposing these complexes as a new class of antimetabolites.

Single crystals of three novel transition-metal oxalates, dirubidium di-aqua-dioxalatocobalt(II) dihydrate or dirubidium cobalt(II) bis-(oxalate) tetra-hydrate, Rb 2 [Co(C 2 O 4 ) 2 (H 2 O) 2 ]·2H 2 O, (I), catena -poly[dirubidium [[di-chlorido-cobalt(II)]-μ-oxalato]] or dirubidium cobalt(II) dichloride oxalate, {Rb 2 [CoCl 2 (C 2 O 4 )]} n , (II), and poly[dipotassium [tri-μ-oxalato-copper(II)dilithium] dihydrate] or dipotassium dilithium copper(II) tris-(oxalate) dihydrate, {K 2 [Li 2 Cu(C 2 O 4 ) 3 ]·2H 2 O} n , (III), have been grown under hydro-thermal conditions and their crystal structures determined using single-crystal X-ray diffraction. The structure of (I) exhibits isolated octa-hedral [Co(C 2 O 4 ) 2 (H 2 O) 2 ] units, whereas (II) consists of trans chains of Co 2+ ions bridged by bidentate oxalato ligands and (III) displays a novel tri-periodic network of Li + and Cu 2+ ions linked by oxalato bridging ligands., (© Clulow and Lightfoot 2023.)

Naproxen (6-methoxy-α-methyl-2-naphthaleneacetic acid), 1-naphthylacetic acid, 2-naphthylacetic acid and 1-pyreneacetic acid are derivatives of acetic acid bearing a naphthalene-based ring. In the present review, the coordination compounds of naproxen, 1- or 2-naphthylacetato and 1-pyreneacetato ligands are discussed in regard to their structural features (nature and nuclearity of metal ions and coordination mode of ligands), their spectroscopic and physicochemical properties and their biological activities.

The reactions of Zn(NO 3 ) 2 . 6H 2 O and Cd(NO 3 ) 2 . 4H 2 O with KSeCN and 4-meth-yl-pyridine (C 6 H 7 N; 4-picoline) lead to the formation of crystals of bis-(4-methyl-pyridine-κ N )bis-(seleno-cyanato-κ N )zinc(II), [Cd(NCSe) 2 (C 6 H 7 N) 2 ] ( 1 ), and catena -poly[[bis-(4-methyl-pyridine-κ N )cadmium(II)]-di-μ-seleno-cyanato-κ 2 N : Se ;κ 2 Se : N ], [Cd(NCSe) 2 (C 6 H 7 N) 2 ] n ( 2 ), suitable for single-crystal X-ray diffraction. The asymmetric unit of compound 1 consists of one Zn cation that is located on a twofold rotation axis as well as one seleno-cyanate anion and one 4-methyl-pyridine ligand in general positions. The Zn cations are tetra-hedrally coordinated by two terminal N-bonding thio-cyanate anions and two 4-methyl-pyridine ligands, forming discrete complexes. The asymmetric unit of compound 2 consists of two crystallographically independent Cd cations, of which one is located on a twofold rotation axis and the second on a center of inversion, as well as two crystallographically independent seleno-cyanate anions and two crystallographically independent 4-methyl-pyridine ligands in general positions. The Cd cations are octa-hedrally coordinated by two N- and two S-bonding seleno-cyanate anions and two 4-methyl-pyridine ligands and are linked into chains by pairs of seleno-cyanate anions. Within the chains, the Cd cations show an alternating cis - cis - trans and all - trans coordination and therefore, the chains are corrugated. PXRD investigations prove that the Zn compound was obtained as a pure phase and that the Cd compound contains a very small amount of an additional and unknown phase. In the IR spectrum of 1 , the CN stretching vibration of the seleno-cyanate anion is observed at 2072 cm -1 , whereas in the 2 it is shifted to 2094 cm -1 , in agreement with the crystal structures., (© Näther and Jess 2023.)

NIR emitting OLEDs (organic light-emitting diodes) with high photoluminescence quantum yields were developed on the basis of fluorinated 1,3-diketonate coordination compounds of the Nd 3+ ion. Both thermal evaporation and spin-coating techniques were successfully employed for active layer deposition resulting in electroluminescence quantum yields up to 1.38·10 -2 %. Blueish-green emission from exciplex and electroplax formations was almost suppressed with the topology optimization of the cell.

2-Formylpyridine thiosemicarbazone - iron (III) chelates [ F e L 2 ] C l • 2 H 2 O {L = L 1 ( C1 ) [ HL 1  = 4-(4-Nitrophenyl)-1-((pyridin-2-yl)methylene)thiosemicarbazide] and L = L 2 ( C2 ) [ HL 2  = 4-(2,5-Dimethoxyphenyl)-1-((pyridin-2-yl)methylene)thiosemicarbazide]} were prepared. The two ligand anions in each complex resulted in saturation of the iron coordination number and consequently the existence of these complexes as 1:1 electrolytes. As well, the iron in these complexes exhibits low-spin electronic configuration. X-ray crystallography of complex C1 indicated its triclinic crystal system and P 1 ‾ space group. In addition, it proved the ligation through a thiol sulfur atom and two nitrogen atoms of pyridine and azomethine groups. This is while the presence of two water molecules of crystallization in the complex structure was also indicated. The ligand HL 1 was selected for cytotoxicity screening against human MCF-7, A-549, HEPG-2 and HCT-116 cancer cells and the most enhanced activities were detected against the breast cells. Against these cells, the compounds HL 1 , HL 2 , C1 and C2 induced cytotoxicity, respectively, with IC 50 values of 52.4, 145.4, 34.3 and 62.0 μM. However, against the healthy BHK cells, HL 1 and HL 2 caused cytotoxicity, respectively, with IC 50 values of 54.8 and 110.6 μM and cytotoxicity with percent viabilities of 56.7 and 55.4% of the BHK cells by the complexes (137.4 μM of C1 and 131.9 μM of C2 ) was determined. These activities against MCF-7 cells are less significant compared with the measured value for doxorubicin. But this standard is more toxic to normal cells than the thiosemicarbazones (IC 50 (doxorubicin) = 9.66 μM against MCF-7 cells and 36.42 μM against BHK cells)., (© 2023 The Authors.)

Leishmaniasis is a neglected disease caused by protozoa belonging to the Leishmania genus. Notably, the search for new, promising and potent anti- Leishmania compounds remains a major goal due to the inefficacy of the available drugs used nowadays. In the present work, we evaluated the effects of 1,10-phenanthroline-5,6-dione (phendione) coordinated to silver(I), [Ag(phendione) 2 ]ClO 4 (Ag-phendione), and copper(II), [Cu(phendione) 3 ](ClO 4 ) 2 ·4H 2 O (Cu-phendione), as potential drugs to be used in the chemotherapy against Leishmania amazonensis and Leishmania chagasi . The results showed that promastigotes treated with Ag-phendione and Cu-phendione presented a significant reduction in the proliferation rate. The IC 50 values calculated to Ag-phendione and Cu-phendione, respectively, were 7.8 nM and 7.5 nM for L. amazonensis and 24.5 nM and 20.0 nM for L. chagasi . Microscopical analyses revealed several relevant morphological changes in promastigotes, such as a rounding of the cell body and a shortening/loss of the single flagellum. Moreover, the treatment promoted alterations in the unique mitochondrion of these parasites, inducing significant reductions on both metabolic activity and membrane potential parameters. All these cellular perturbations induced the triggering of apoptosis-like death in these parasites, as judged by the (i) increased percentage of annexin-positive/propidium iodide negative cells, (ii) augmentation in the proportion of parasites in the sub-G 0 /G 1 phase and (iii) DNA fragmentation. Finally, the test compounds showed potent effects against intracellular amastigotes; contrarily, these molecules were well tolerated by THP-1 macrophages, which resulted in excellent selective index values. Overall, the results highlight new selective and effective drugs against Leishmania species, which are important etiological agents of both cutaneous ( L. amazonensis ) and visceral ( L. chagasi ) leishmaniasis in a global perspective.

A new ligand 5-((1-methyl-pyrrol-2-yl) methyl)-4-(naphthalen-1-yl)-1,2,4-triazoline-3-thione (C15) and its metal complexes with formulae: Mn(C15)Cl 2 MeOH ( 1 ), Fe(C15)Cl 2 MeOH ( 2 ), Ni(C15)Cl 2 MeOH ( 3 ), Cu(C15) 2 Cl 2 ( 4 ) and Zn(C15) 4 Cl 2 ( 5 ) have been synthesized. The C15 ligand and complexes were characterized by NMR, elemental analysis, FT-IR, EPR, magnetic and TGA studies. The anticancer activities of the organic ligand (C15) and complexes ( 1 - 5 ) were evaluated against human colon adenocarcinoma (HT29) and human lung (A549) cancer cell lines. The complex ( 1 ) exhibited potential activity at concentration of 794.37 μM (A549) and 654.31 μM (HT29) in both cancer cells. The complex ( 3 ) showed significant activity against the HT29 cancer cell line with an IC 50 value of 1064.05 μM. This article highlights some of the metals that have become important in the development of new coordination complexes and the treatment of cancer. Additionally, for C15, the toxicity was predicted by ADMET analysis and molecular docking.

Substitution of the chlorido ligand of cyclometalated [Pt (5-R-1,3-di(2-pyridyl) benzene)Cl] (R = methyl, mesityl, 2-thienyl, or 4-diphenylamino-phenyl) by 4-phenylthiazole-2-thiolate leads to related thiolato complexes, which were fully characterized. Their photophysical properties were determined in degassed dichloromethane solution. The emission color of the novel complexes can be easily tuned by the nature of the substituents on the terdentate ligand, as is the case for the parent chlorido complexes. Their luminescence Quantum Yield is high, with that of the compounds with the 2-thienyl or 4-diphenylamino-phenyl substituents being much higher than that of the related chloride complexes. The platinum complex with the cyclometalated 5-(2-thienyl)-1,3-di(2-pyridyl) benzene was used as the emitter for the fabrication of a yellow solution-processable OLED.

New lanthanide dimethyl-N-benzoylamidophosphate (HL) based tetrakis-complexes NEt 4 [LnL 4 ] (Ln 3+ =La, Nd, Sm, Eu, Gd, Tb, Dy) are reported. The complexes are characterized by means of NMR, IR, absorption, and luminescent spectroscopy as well as by elemental, X-Ray, and thermal gravimetric analyses. The phenyl groups of the four ligands of the complex anion are directed towards one side, while the methoxy groups are directed in the opposite side, which makes the complexes under consideration structurally similar to calixarenes. The effect of changing the alkali metal counterion to the organic cation NEt 4 + on the structure and properties of the tetrakis-complex [LnL4] - is analyzed. The complexes exhibit bright characteristic for respective lanthanides luminescence. Rather high intensity of the band of 5 D 0 → 7 F 4 transition, observed in the luminescence spectrum of NEt 4 [EuL 4 ], is discussed based on theoretical calculations., (© 2022 Wiley-VCH GmbH.)

Developing new, smart drugs with the anticancer activity is crucial, especially for cancers, which cause the highest mortality in humans. In this paper we describe a series of coordination compounds with the element of health, zinc, and bioactive ligands, benzimidazole derivatives. By way of synthesis we have obtained four compounds named C1 , C2 , C4 and C4. Analytical analyses (elemental analysis (EA), flame atomic absorption spectrometry (FAAS)), spectroscopic (Fourier transform infrared spectroscopy (FT-IR), mass spectrometry (MS)) and thermogravimetric (TG) methods and the definition of crystal structures were used to explore the nature of bonding and to elucidate the chemical structures. The collected analytical data allowed the determination of the stoichiometry in coordination compounds, thermal stability, crystal structure and way of bonding. The cytotoxicity effect of the new compounds as a potential antitumor agent on the glioblastoma (T98G), neuroblastoma (SK-N-AS) and lung adenocarcinoma (A549) cell lines and human normal skin fibroblasts (CCD-1059Sk) was also determined. Cell viability was determined by the MTT assay. The results obtained confirmed that conversion of ligands into the respective metal complexes significantly improved their anticancer properties. The complexes were screened for antibacterial and antifungal activities. The ADME technique was used to determine the physicochemical and biological properties.

Aqueous zinc (Zn) metal batteries have been regarded as the most promising aqueous batteries due to their low redox potential, high theoretical capacity, and abundant Zn resources. Unfortunately, Zn dendrite growth and serious side reactions drastically curtail the cycle life, severely affecting their large-scale application. Herein, a multifunctional ordered Zn-aminotrimethylene phosphonic acid (Zn-ATMP) film is in situ modified on the surface of metal Zn via a facile etching process. The modified layer can not only retard the side reactions and suppress the corrosion rate, but also lower the Zn nucleation overpotential and accelerate diffusion and homogenize deposition of Zn 2+ due to the strong Zn affinity. Consequently, the as-prepared Zn-ATMP@Zn anode in the symmetric cell enables long-term lifespan (over 1000 h) at 10.0 mA cm -2 with a high areal capacity of 5 mAh cm -2 . Furthermore, when assembled with a SeS 2 -based cathode, a long lifespan for over 280 cycles at 2 C can be achieved for the aqueous Zn-SeS 2 battery. This work provides a reliable strategy for constructing stabilized Zn anode and accelerating the development of an aqueous energy storage system., (© 2022 Wiley-VCH GmbH.)

Tackling microbial resistance requires continuous efforts for the development of new molecules with novel mechanisms of action and potent antimicrobial activity. Our group has previously identified metal-based compounds, [Ag(1,10-phenanthroline-5,6-dione) 2 ]ClO 4 (Ag-phendione) and [Cu(1,10-phenanthroline-5,6-dione) 3 ](ClO 4 ) 2 .4H 2 O (Cu-phendione), with efficient antimicrobial action against multidrug-resistant species. Herein, we investigated the ability of Ag-phendione and Cu-phendione to bind with double-stranded DNA using a combination of in silico and in vitro approaches. Molecular docking revealed that both phendione derivatives can interact with the DNA by hydrogen bonding, hydrophobic and electrostatic interactions. Cu-phendione exhibited the highest binding affinity to either major (- 7.9 kcal/mol) or minor (- 7.2 kcal/mol) DNA grooves. In vitro competitive quenching assays involving duplex DNA with Hoechst 33258 or ethidium bromide demonstrated that Ag-phendione and Cu-phendione preferentially bind DNA in the minor grooves. The competitive ethidium bromide displacement technique revealed Cu-phendione has a higher binding affinity to DNA (K app  = 2.55 × 10 6  M -1 ) than Ag-phendione (K app  = 2.79 × 10 5  M -1 ) and phendione (K app  = 1.33 × 10 5  M -1 ). Cu-phendione induced topoisomerase I-mediated DNA relaxation of supercoiled plasmid DNA. Moreover, Cu-phendione was able to induce oxidative DNA injuries with the addition of free radical scavengers inhibiting DNA damage. Ag-phendione and Cu-phendione avidly displaced propidium iodide bound to DNA in permeabilized Pseudomonas aeruginosa cells in a dose-dependent manner as judged by flow cytometry. The treatment of P. aeruginosa with bactericidal concentrations of Cu-phendione (15 µM) induced DNA fragmentation as visualized by either agarose gel or TUNEL assays. Altogether, these results highlight a possible novel DNA-targeted mechanism by which phendione-containing complexes, in part, elicit toxicity toward the multidrug-resistant pathogen P. aeruginosa., (© 2022. The Author(s).)

In the title polymeric coordination compound, {[FePt(CN) 4 (H 2 O) 2 ]·1.33CH 3 OH} n , the Fe II cation (site symmetry 4/ mm.m ) is coordinated by the N atoms of four cyanide anions (CN - ) and the O atoms of two water mol-ecules, forming a nearly regular [FeN 4 O 2 ] octa-hedron. According the Fe-N and Fe-O bond lengths, the Fe II atom is in the high-spin state. The cyanide anions act in a bridging manner to connect the Fe II and Pt II atoms. The [Pt(CN) 4 ] 2- moieties (Pt with site symmetry 4/ mm.m ) have a perfect square-planar shape. The latter anion is located perpendicular to the FeN 4 plane, thus ensuring the creation of a three-dimensional framework. The crystal structure features methanol solvent mol-ecules of which 4/3 were located per Fe II cation. These solvent mol-ecules are located in hexa-gonal pores; they inter-act with coordinating water mol-ecules through weak hydrogen bonds. Other guest mol-ecules could not be modelled in a satisfactory way and their contribution to the scattering was removed by a mask procedure., (© Hiiuk et al. 2022.)

The aquatic infectious pancreatic necrosis virus (IPNV) causes a severe disease in farmed salmonid fish that generates great economic losses in the aquaculture industry. In the search for new tools to control the disease, in this paper we show the results obtained from the evaluation of the antiviral effect of [Cu(NN 1 ) 2 ](ClO 4 ) Cu(I) complex, synthesized in our laboratory, where the NN 1 ligand is a synthetic derivate of the natural compound coumarin. This complex demonstrated antiviral activity against IPNV at 5.0 and 15.0 µg/mL causing a decrease viral load 99.0% and 99.5%, respectively. The Molecular Docking studies carried out showed that the copper complex would interact with the VP2 protein, specifically in the S domain, altering the process of entry of the virus into the host cell.

Copper is an endogenous metal ion that has been studied to prepare a new antitumoral agent with less side-effects. Copper is involved as a cofactor in several enzymes, in ROS production, in the promotion of tumor progression, metastasis, and angiogenesis, and has been found at high levels in serum and tissues of several types of human cancers. Under these circumstances, two strategies are commonly followed in the development of novel anticancer Copper-based drugs: the sequestration of free Copper ions and the synthesis of Copper complexes that trigger cell death. The latter strategy has been followed in the last 40 years and many reviews have covered the anticancer properties of a broad spectrum of Copper complexes, showing that the activity of these compounds is often multi factored. In this work, we would like to focus on the anticancer properties of mixed Cu(II) complexes bearing substituted or unsubstituted 1,10-phenanthroline based ligands and different classes of inorganic and organic auxiliary ligands. For each metal complex, information regarding the tested cell lines and the mechanistic studies will be reported and discussed. The exerted action mechanisms were presented according to the auxiliary ligand/s, the metallic centers, and the increasing complexity of the compound structures.

The synthesis and biological evaluation of 5-arylidene-N-acetyl-tetramic acids cadmium(II) complexes are reported. Eleven novel compounds were prepared, characterized by nuclear magnetic resonance experiments and screened for their antimicrobial activity against five bacterial species (Escherichia coli, Klebsiella pneumoniae, Acinetobacter baumannii, Pseudomonas aeruginosa, and methicillin-resistant Staphylococcus aureus [MRSA]) and two fungi (Candida albicans and Cryptococcus neoformans). The complexes showed similar or enhanced activities against MRSA in comparison to the corresponding ligands and, additionally, promising antifungal activities against C. neoformans. The most active compounds 3c and 3h showed remarkable activities against MRSA (minimum inhibitory activity [MIC] values of 32 and 4 μg/ml, respectively) and C. neoformans (MIC values of 8 and 16 μg/ml, respectively), accompanied by no human cell toxicity and hemolytic activity within the tested concentration range. The results demonstrate that appropriately functionalized tetramic acids attached with lipophilic alkanoyl chain and after complexation with cadmium(II) ions may act as valuable lead compounds for further investigations toward the development of novel antibacterial and/or antifungal agents., (© 2021 Deutsche Pharmazeutische Gesellschaft.)

One important property of tannins involves their ability to form coordination compounds with metal ions, which is vital for the bioavailability of these ions, as well as for the antibacterial and antioxidative activities of tannins. In this study, the pH dependence of interactions between gallic acid, one of the basic building blocks of tannins, and Fe(II) ions, was investigated using UV/Vis spectroscopy, in conjunction with density functional theory (DFT) calculations. Moreover, two models were developed to explain the processes taking place in the solution. The first model treated the reaction as a simple bimolecular process while the second also considered the protolytic equilibrium, which was proven very successful in discerning the pH dependence of formation constants, and whose assumptions were well supported by DFT calculations. We showed that the two-time deprotonated gallic acid species forms the coordination compound with Fe(II) ions in a 1:1 molar ratio. To gain better insight into the process, the coordination compound formation was also studied using various DFT functionals, which further supported the model results. Furthermore, due to the relatively low sample amounts needed, the methodology developed here will be useful to study compounds that are more difficult to isolate.

Coordination compounds including mainstream metal-organic frameworks and Prussian blue analogues receive extensive researches when they directly serve as electrocatalysts. Their reconstruction phenomena, that are closely associated with actual contributions and intrinsic catalytic mechanisms, are expected to be well summarized. Here, the recent advances in understanding reconstruction chemistry of coordination compounds are reviewed, including their main classifications and structural properties, reconstruction phenomena in electrocatalysis (e.g., oxygen/hydrogen evolution reaction, CO 2 reduction), influence factors of reconstruction parameters (e.g., reconstruction rate and reconstruction degree), and reconstruction-performance correlation. It is outlined that the reconstruction processes are influenced by electronic structure of coordination compounds, pH and temperature of testing solution, and applied potentials. The characterization techniques reflecting the evolution information before and after catalysis are also introduced for reconstruction-related mechanistic study. Finally, some challenges and outlooks on reconstruction investigations of coordination compounds are proposed, and the necessity of studying and understanding of these themes under actual working conditions of devices is highlighted., (© 2021 Wiley-VCH GmbH.)

Four chiral coordination polymers (CPs), M[(S,S)-C 14 H 14 N 2 O 6 ] and M[(R,R)-C 14 H 14 N 2 O 6 ] (M=Zn or Cd), have been exclusively synthesized in high yields with the aid of newly designed chiral ligand under hydrothermal condition. The CPs crystallizing in the orthorhombic nonpolar space group, C222 1 , reveal three-dimensional framework structures composed of MO 4 tetrahedra and the corresponding homochiral linkers. Powder second-harmonic generation (SHG) measurements indicate that the nonpolar CPs reveal very strong SHG efficiency of ca. 5-9 times that of KH 2 PO 4 and exhibit type-I phase-matching behavior. Density functional theory calculations suggest that the unusually large SHG efficiency found from the nonpolar CPs should be attributable to the synergistic effect of polarizable metal cations and enhanced hyperpolarizability in the donor-acceptor system originating from the hydrogen bonding in the coordinated linkers., (© 2021 Wiley-VCH GmbH.)

Among transition and non-transition metals, thallium is a unique case of an element which, despite its known toxicity, provides interesting challenges through its biology and chemistry linked to diagnosis of human pathophysiologies. Poised to investigate in-depth the structural and electronic aspects of thallium involvement in physiological processes, the synthetic exploration of aqueous binary systems of Tl(I) with physiological binders from the family of hydroxycarboxylic acids (glycolic, lactic, mandelic and citric acid) was pursued in a pH-specific fashion. The isolated crystalline coordination polymers, emerging from that effort, were physicochemically characterized through elemental analysis, FT-IR, ESI-MS, 1 H-/ 13 C-NMR, and X-ray crystallography. The coordination environment of thallium in each molecular Tl(I) assembly, along with lattice dimensionality (2D3D), reflects the contributions of the ligands, collectively exemplifying interactions probed into though BVS and Hirshfeld surface analysis. The results portray a well-defined solid-state and solution profile for all species investigated, thereby providing the basis for their subsequent selection into in vitro biological studies involving the (patho)physiological cell lines 3T3-L1, Saos-2, C2C12, and MCF-7. Biotoxicity profiles, encompassing cell viability, morphology, and cell growth support clearly a concentration-, time-, and cell tissue-specific behavior for the chosen Tl(I) compounds in a structure-specific fashion. Collectively, the chemical experimental data support the biological results in formulating a structure-specific behavior for Tl(I)-hydroxycarboxylato species with respect to biotoxicity mechanisms in a (patho)physiological environment. The accrued knowledge stands as the foreground for further investigation into the relevant biological chemistry of Tl(I) and molecular technologies targeting its sequestration and removal from cellular media., (Copyright © 2021 Elsevier Inc. All rights reserved.)