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The dynamics of lysozyme is probed by attaching –SCN to all alanine residues. The one-dimensional infrared spectra exhibit frequency shifts in the position of the maximum absorption of 4 cm−1, which is consistent with experiments in different solvents and indicates moderately strong interactions of the vibrational probe with its environment. Isotopic substitution 12C → 13C leads to a redshift by −47 cm−1, which agrees quantitatively with experiments for CN-substituted copper complexes in solution. The low-frequency, far-infrared part of the protein spectra contains label-specific information in the difference spectra when compared with the wild type protein. Depending on the position of the labels, local structural changes are observed. For example, introducing the –SCN label at Ala129 leads to breaking of the α-helical structure with concomitant change in the far-infrared spectrum. Finally, changes in the local hydration of SCN-labeled alanine residues as a function of time can be related to the reorientation of the label. It is concluded that –SCN is potentially useful for probing protein dynamics, both in the high-frequency part (CN-stretch) and in the far-infrared part of the spectrum. [ABSTRACT FROM AUTHOR]

Copper(III) iodide and bromide complexes representing a unique combination of highly‐coordinated metal and soft polarizable anions were synthesized and fully characterized, including X‐ray crystallography. Ligand substitution in well‐defined highly‐coordinated copper complex PyCu(CF3)3 with pincer ligands was achieved to give formally octahedral copper(III) complexes. [ABSTRACT FROM AUTHOR]

The preparation of cationic bis(hydrosilane)–coinage‐metal complexes by chloride abstraction from the neutral metal chloride precursors with Na[BArF4] is described. Unlike previously reported hydrosilane‐stabilized copper and silver complexes, the presented complexes are cationic and feature two bidentate (ortho‐silylphenyl)phosphine ligands. These complexes were fully characterized by NMR spectroscopy and X‐ray diffraction analysis, revealing that both Si−H bonds are activated by the Lewis acidic cationic metal center. The new complexes were found to be effective in catalytic carbonyl hydrosilylation, leading to the corresponding silyl ethers under mild conditions without the addition of an external base. Combined mechanistic control experiments and quantum chemical calculations support an ionic outer‐sphere mechanism, in which a neutral metal alkoxide species instead of a metal hydride is the key intermediate that interacts with the silylcarboxonium ion to generate the silyl ether. [ABSTRACT FROM AUTHOR]

Triboluminescence is a phenomenon in which light is generated through mechanical stress; it has emerging applications in stress‐sensing devices. Although the prevailing mechanistic model indicates that light emits from charge separation and recombination in fracture planes arising from polar structures, its application in designing triboluminescent materials remains limited owing to numerous exceptions. This study provides insights into the essential requirements for triboluminescence by investigating the structural and electrostatic properties of fractured crystals of copper thiocyanate complexes. The examined fracture plane indicated that charge pairs (which are essential for light emission) form when intermolecular interactions are disrupted during fracturing. On the basis of the nature of these charges, we successfully suppressed triboluminescence by inhibiting the formation of intermolecular interactions disrupted in the examined complexes. Furthermore, we induced its re‐emergence by creating an alternative fracture plane through controlled manipulation of the molecular network. This demonstrative deactivation and reactivation of triboluminescence underscores the critical role of intermolecular disruption in generating charge pairs, a prerequisite for triboluminescence. [ABSTRACT FROM AUTHOR]

We report the synthesis and full characterization of the copper dinitrogen complex [(η1‐N2)Cu{Al(ORF)4}] 2 (RF=C(CF3)3) prepared by a cascade metathesis reaction of Ag[Al(ORF)4] with CuI‐excess in iso‐perfluorohexane (i‐pfh) under N2 atmosphere. Title compound 2 features an extraordinarily high N2 stretching frequency at 2313/2314 cm−1 (IR/Raman) and was characterized by single‐crystal and powder X‐ray diffractometry. Quantum chemical charge displacement analysis based on natural orbitals of chemical valence (CD‐NOCV) indicates that the copper‐dinitrogen interaction is still governed by weak π‐backdonation, but is significantly reduced compared to all literature‐known transition metal dinitrogen complexes. [ABSTRACT FROM AUTHOR]

ABSTRACT Copper complexes exhibit promising anticancer properties, which can be further promoted by suitable ligands. In this study, we synthesized and investigated the anticancer effects of three copper(I) complexes with N‐heterocyclic carbene (NHC) ligands derived from phenanthroline‐functionalized imidazole salts. The synthesis of these NHC‐copper(I) complexes (Cu1‐Cu3) was meticulously characterized using NMR and elemental analysis; their crystal structures were further delineated by X‐ray diffraction. Our findings illustrate the unique geometric configurations of these complexes: Cu1 features a dinuclear arrangement with off‐linear geometry; Cu2 and Cu3 are characterized by a bi‐copper core stabilized by two phenanthroline‐modified carbene ligands. Crucially, in vitro cytotoxic evaluations revealed that these complexes possess suitability anticancer activity. Among them, Cu2 exhibited enhanced cytotoxicity activity, achieving a half‐maximal inhibitory concentration (IC50) of 4.36 ± 0.25 μM in colon cancer cell line HCT‐116, markedly surpassing the efficacy of cisplatin. Subsequent investigations elucidated that Cu2 notably increases intracellular reactive oxygen species (ROS) levels and induces mitochondrial membrane depolarization and endoplasmic reticulum stress, leading to oxidative stress‐mediated apoptosis of colon cancer cells. [ABSTRACT FROM AUTHOR]

The synthesis and characterization of metal complexes have garnered significant attention due to their versatile applications in scientific and biomedical fields. In this research, two novel copper (Cu) complexes, [Cu(L)(L′)(H2O)2] (1) and [Cu(L)(Im)H2O] (2), where L = pyridine-2,6-dicarboxylic acid, L′ = 2,4-diamino-6-hydroxypyrimidine, and Im = imidazole, were investigated concerning their sonochemical synthesis, spectroscopic analysis, and biological activity. The complexes' structural characterization was achieved using analytical techniques, including single-crystal X-ray structure determination, FTIR, PXRD, TGA and DTA, SEM, TEM, and EDS. Complex (1) displayed a six-coordinated Cu2+ ion, while complex (2) exhibited a five-coordinated Cu2+ ion. The crystal structures revealed monoclinic (C2/c) and triclinic (P-1) space groups, respectively. Both complexes showcased zero-dimensional (0D) supramolecular networks, primarily driven by hydrogen bonding and π–π stacking interactions, which played pivotal roles in stabilizing the structures and shaping the unique supramolecular architecture. Both complexes demonstrated significant antioxidant activity, suggesting their capability to neutralize free radicals and mitigate oxidative stress-related diseases. Hemolysis percentages were less than 2%, per the ASTM F756-00 standard, indicating non-hemolytic behavior. Low cytotoxicity was observed against fibroblast and MCF-7 cell lines. They do not exhibit antibacterial activity against Escherichia coli and Staphylococcus aureus. These findings suggest that the synthesized Cu2+‒complexes hold considerable promise for applications in drug delivery and cancer treatment. This research contributes to the advancement of supramolecular chemistry and the development of multifunctional materials for diverse scientific and medical applications. [ABSTRACT FROM AUTHOR]

In this study, the reaction between 2-(3,5-dimethylpyrazolylmethyl)-5-(dimethylaminomethyl)pyrrole and thiophenol under heating conditions afforded the new ligand 2-(3,5-dimethylpyrazolylmethyl)-5-(phenylthiomethyl)pyrrole 2. The reaction of 2 with meta-chloroperbenzoic acid provided sulfoxide 3 and sulfone 4 group-containing ligands. The reaction of 2 with copper(I) halides provided the binuclear complexes [Cu(μ-X){μ-C4H3N-2-(CH2Me2pz)-5-(CH2SPh)-κ2-S,N}]2 (X = Cl, Br and I, 5–7) in high yields. Conversely, the analogous reaction of 4 with copper(I) halides yielded two types of complexes, three coordinate bi- and mononuclear of the type [Cu(μ-Cl){C4H3N-2-(CH2Me2pz)-5-(CH2SO2Ph)-κ1-N}]28 and [CuX{C4H3N-2-(CH2Me2pz)-5-(CH2SO2Ph)-κ1-N}2], X = Br, 9 and I, 10. When the reaction was carried out in the presence of KPF6, the two-coordinate complex [Cu{C4H3N-2-(CH2Me2pz)-5-(CH2SO2Ph)-κ1-N}2]PF6−11a was isolated, whereas its BF4− analogue 11b was synthesized by the reaction of 8 with AgBF4. The structures of these complexes were determined using single-crystal X-ray crystallography. These copper complexes catalyzed the hydroamination–alkynylation reaction between several secondary amines and alkyl and aryl terminal alkynes. Using 1 mol% of complexes 5–10 as catalysts, both tri- and tetra-substituted propargylamines were isolated. Alternatively, phenylacetylene and different secondary amines afforded the corresponding trisubstituted propargylamines as the major products and alkyl terminal alkynes gave the tetrasubstituted products in excellent yields. In addition, the role of counter anions such as TfO−, PF6−, BF4−, PO43− and Ph4B− on the product selectivity was studied. When fluorinated anions such as TfO−, PF6−, and BF4− were present with the copper complexes, the hydroamination–hydrovinylation product 1-aminodiene 23 was observed, which was not formed with PO43−, Ph4B− or halide ions. Specifically, TfO− and PF6− favored the formation of 23, while BF4− favored the tetrasubstituted product as the major product. This was further supported by the isolated copper(I) complexes containing PF6− and BF4− and by other specific reactions. The peaks for enamines and [LCu]+ species in the HRMS spectra of the reaction mixtures and the isolation of the morpholinium copper(I) salt support the proposed mechanism. [ABSTRACT FROM AUTHOR]

In situ growth of intertwined trinuclear copper complexes (nCu3) on a cellulose-derived carbon support (CMC) produced a high-performance electrocatalyst (CMC–nCu3) for the oxygen reduction reaction (ORR), which demonstrated superior performance in zinc–air batteries compared to a commercial Pt/C catalyst. This work highlights the importance of copper-based molecular catalysts with rich and intertwined tricopper structures for boosting both ORR activity and stability. [ABSTRACT FROM AUTHOR]

The study results of the copper influence on the thermal decomposition kinetics of complex nitrogen–phosphorus–potassium chloride-containing ammonium nitrate-based fertilizers with different molar ratios of ammonia to phosphoric acid by thermogravimetry and differential scanning calorimetry are presented. Measurements are taken in non-isothermal conditions at constant heating rates in the temperature range of 20–250 °C. Calculations of the decomposition rate and the heat release rate depending on the extent of decomposition under isothermal conditions are performed by the Friedman isoconversional method. Based on the conducted research results, conclusions about the causes of the copper influence in a complex fertilizer composition on the thermal decomposition kinetics are made. It is shown that in the presence of copper in chloride-containing ammonium nitrate-based fertilizers the decomposition and heat release rates, and the magnitude of exothermic decomposition effect increase. It was also found that copper compounds do not affect the initial decomposition stage. [ABSTRACT FROM AUTHOR]

The corrosion resistance of modification rubberwood with micro sized copper zinc compounds (MCZ) can reach the national level I corrosion resistance standard, but in order to adapt to complex environmental applications, the leaching resistance and dimensional stability need to be further improved. Propylene glycol was used to modify MCZ, and then combined with tannin-boric acid for synergistic treatment of rubberwood. The results showed that when the rubberwood was impregnated with PG-MCZ and modified with tannin-boric acid with a mass concentration of 1%, the leaching resistance of the treated wood was the best. At this point, the modified rubberwood had the best anti moisture expansion and anti drying shrinkage effects, and the best dimensional stability. Although the addition of propylene glycol slightly weakened the corrosion resistance of rubberwood, it can still meet the national level I corrosion resistance standard and improve flame retardancy and smoke suppression of rubberwood. This study has a positive effect on promoting the development and utilization of environmentally friendly wood preservatives. [ABSTRACT FROM AUTHOR]

• Research on emerald green pigment degradation is on systematic samples. • 5 different emerald green degradation products were obtained in 15 systematic samples. • Evidence for emerald green pigment degradation process was found. • The possible degradation process of emerald green pigment was pointed out. • The change from green to blue was determined to be caused by Lavendulan. Emerald green pigment was widely used in painted cultural artifacts during the 19th and 20th centuries. However, this pigment is inherently unstable, leading to a certain degree of degradation, thereby capturing the widespread attention of research scholars due to its degradation mechanisms. Previous studies primarily relied on the compositional analysis of individual samples, thus only observing the results of the degradation at a certain stage without reflecting the dynamic process of change. The Sichuan region in China hosts a large number of grottoes and cliff statues, many of which have undergone modern repainting. Focusing on the green pigment from these cultural relics, this research aims to capture the degradation products of emerald green at different stages. This approach promises a more systematic and comprehensive understanding of the degradation process, consequently advancing the exploration of its degradation mechanisms. In this study, 15 green pigment samples from five different painted grottoes in the Sichuan region were collected for analysis. Employing technological analytical methods, the presence of emerald green pigment (Cu(C 2 H 3 O 2) 2 ·3Cu(AsO 2) 2) was identified, along with several other substances containing Cu and As elements, such as Lavendulan (NaCaCu 5 (AsO 4) 4 Cl·5H 2 O), copper arsenate (Cu 3 (AsO 4) 2), alkaline arsenate copper compounds Cu 3 (AsO 4)(OH) 3 , Cu 2 (AsO 4)(OH)·3H 2 O and Cu(AsO 3 OH)·2H 2 O. The elemental compositions, chemical structures, and Raman spectra of these substances exhibit obvious connections and progressive relationships. This study, for the first time, elucidates the diverse degradation products of emerald green pigment from cultural artifacts within similar coexistence environments. It outlines a tentative degradation route, namely: (1) Oxidation and decomposition of Cu(C 2 H 3 O 2) 2 ·3Cu(AsO 2) 2 → Formation of Cu 3 (AsO 4) 2 , alkaline arsenate copper compounds and Ca(C 2 O 4)·H 2 O; (2) Transformation of Cu 3 (AsO 4) 2 , alkaline arsenate copper compounds→ Formation of NaCaCu 5 (AsO 4) 4 Cl·5H 2 O. Throughout this process, the macroscopic color changes from green to blue. Emerald green pigment has been widely used in painted cultural relics from the late Qing Dynasty to modern times in China. This pigment has obvious degradation phenomenon and will gradually show a blue tint. At present, research on the pigment degradation process is still insufficient. This study is the first to analyze the different intermediate products of emerald pigment from a large number of systematic cultural relic samples, and roughly lists its degradation process. [Display omitted] [ABSTRACT FROM AUTHOR]

The title compound, bis[μ-2,2′-(4H-1,2,4-triazole-3,5-diyl)diacetato]bis[diaquacopper(II)] dihydrate, [Cu2(C6H5N3O4)2(H2O)4]·2H2O, is a dinuclear octahedral CuII triazole-based complex. The central copper atoms are hexa-coordinated by two nitrogen atoms in the equatorial positions, two equatorial oxygen atoms of two carboxylate substituents in position 3 and 5 of the 1,2,4-triazole ring, and two axial oxygen atoms of two water molecules. Two additional solvent water molecules are linked to the title molecule by O—H⋯N and O⋯H—O hydrogen bonds. The crystal structure is built up from the parallel packing of discrete supramolecular chains running along the a-axis direction. Hirshfeld surface analysis suggests that the most important contributions to the surface contacts are from H⋯O/O⋯H (53.5%), H⋯H (28.1%), O⋯O (6.3%) and H⋯C/C⋯H (6.2%) interactions. The crystal studied was twinned by a twofold rotation around [100]. [ABSTRACT FROM AUTHOR]

Synthesis, characterization and structural relevance of four new copper carboxylate complexes (1–4) has been presented here. The complexes have been synthesized by direct treatment of the substituted phenyl acetate and pyridine ligands in aqueous medium. The complexes were stable indefinitely with excellent yields and were characterized using spectroscopic and single crystal XRD techniques. FTIR spectroscopy revealed the bridging bidentate coordination mode for the carboxylate moiety in accordance to the actual structure revealed by XRD. Moreover, UV-Visible spectroscopic and cyclic voltammetric studies helped in their characterization and yielded signals which were typical of the copper(II) complexes. Successfully solved single crystal XRD data showed binuclear paddlewheel structures for all the complexes with both copper ions linked through four OCO bridges of ortho-methoxy phenyl acetate (1–3) and ortho-methyl-meta-nitrophenyl acetate (4). The geometry around each copper was distorted square pyramidal where the apical positions are occupied by meta-bromopyridine (1), meta-methylpyridine (2) and DMSO (3 and 4) molecules. The complexes exhibited excellent DNA-binding activity majorly via intercalation as revealed by four experimental techniques. This preliminary study showed that the synthesized complexes add to the existing treasury on the paddlewheel complexes. Air stable newly synthesized and purified crystalline complexes with their preliminary structural relevance. [ABSTRACT FROM AUTHOR]

Copyright of Przegląd Elektrotechniczny is the property of Przeglad Elektrotechniczny and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Gold extraction has long relied on cyanidation yet faces challenges including toxicity and refractory ore usage. This study explores the glycine-copper-cyanide leaching system's potential for gold recovery from sedimentary rock-hosted disseminated Agh-Darreh gold ore. Initially, cyanidation experiments tested increasing temperatures' impact. Concurrently, classical experiments evaluated key parameters—temperature, time, and sodium cyanide to copper cyanide molar ratio—on gold leaching with glycine. Design of Experiments (DOE) methodology was applied, considering three interaction parameters. Results showed 90% recovery at 50°C, peaking at 93% at 35°C with an 8-h leaching time using the glycine-copper-cyanide system. Increasing the sodium cyanide-to-copper cyanide ratio furthered better gold recovery, attributed to copper glycinate complex formation with glycine, enabling free cyanide redistribution. This study underscores the glycine-copper-cyanide leaching system's efficacy as a cyanidation alternative for efficient gold extraction from sedimentary deposits. [ABSTRACT FROM AUTHOR]

Copyright of Baghdad Science Journal is the property of Republic of Iraq Ministry of Higher Education & Scientific Research (MOHESR) and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Triple-negative breast cancer (TNBC), accounting for 15–20% of all breast cancers, has one of the poorest prognoses and survival rates. Metastasis, a critical process in cancer progression, causes most cancer-related deaths, underscoring the need for alternative therapeutic approaches. This study explores the anti-migratory, anti-invasive, anti-tumoral, and antimetastatic effects of copper coordination compounds Casiopeína IIIia (CasIIIia) and Casiopeína IIgly (CasIIgly) on MDA-MB-231 and 4T1 breast carcinoma cell lines in vitro and in vivo. These emerging anticancer agents, mixed chelate copper(II) compounds, induce apoptosis by generating reactive oxygen species (ROS) and causing DNA damage. Whole-transcriptome analysis via gene expression arrays indicated that subtoxic concentrations of CasIIIia upregulate genes involved in metal response mechanisms. Casiopeínas® reduced TNBC cell viability dose-dependently and more efficiently than Cisplatin. At subtoxic concentrations (IC20), they inhibited random and chemotactic migration of MDA-MB-231 and 4T1 cells by 50–60%, similar to Cisplatin, as confirmed by transcriptome analysis. In vivo, CasIIIia and Cisplatin significantly reduced tumor growth, volume, and weight in a syngeneic breast cancer model with 4T1 cells. Furthermore, both compounds significantly decreased metastatic foci in treated mice compared to controls. Thus, CasIIIia and CasIIgly are promising chemotherapeutic candidates against TNBC. [ABSTRACT FROM AUTHOR]

Two halogenated Schiff bases namely, (E)-1-(((2,6-dichlorophenyl)imino)methyl)naphthalen-2-ol (L1) and (E)-1-(((4-bromo-2,6-dichlorophenyl)imino)methyl)naphthalen-2-ol (L2) were synthesized and reacted with copper(II) nitrate trihydrate in ethanol to give Cu(L1)2 (1) and Cu(L2)2 (2). All the ligands and complexes were successfully characterized using FT-IR, UV-Vis, 1H & 13C-NMR as well as mass spectra and the purity was ascertained by elemental analysis. Electron paramagnetic resonance (EPR) was used to confirm the paramagnetic nature of 1 and 2. Furthermore, the single X-ray crystal structures of 1 and 2 were determined, confirming the formation of mononuclear species in which the Cu(II) center was bonded to two bidentate Schiff bases (L1 or L2) adopting a slightly distorted square planar geometry. Density Function Theory studies revealed that, complex 2 with lowest energy band gap (ΔE) of 2.49 eV is the most reactive among the compounds. α-Amylase and α-glucosidase assays were used to evaluate the antidiabetics potential of the compounds. Complexes 1 and 2 displayed very promising antidiabetic activities with IC50 values of 148.126 mM and 107.786 mM for α-amylase assay while it was 171.559 mM for acarbose (reference drug). The antioxidant potential of the compounds was investigated using nitric oxide (NO), ferric reducing ability power (FRAP) and 2,2-diphenyl-1-picrylhydrazyl (DPPH) assays. The compounds showed moderate to good antioxidant activities with 1 and 2 having IC50 values of 100.044 mM and 247.463 mM for NO scavenging assay, which relatively surpass Vanillin with IC50 value of 466.626 mM. All the compounds showed poor to moderate results against Escherichia coli, Staphylococcus aureus, Bacillus substilis, and Pseudomonas aeruginosa. However, none of them were active against Klebsiella pneumoniae. Generally, 1 and 2 displayed better antidiabetes, antioxidant, and antibacterial potential than L1 and L2. Predicted physicochemical and pharmacokinetic properties of all the compounds showed minimal violation of Lipinski's Ro5. [ABSTRACT FROM AUTHOR]

In a previous study, we showed that the properties and the ability as an entatic state model of copper guanidine quinoline complexes are significantly influenced by a methyl or methyl ester substituent in the 2-position. To prove the importance of the 2-position of the substituent, two novel guanidine quinoline ligands with a methyl or methyl ester substituent in the 4-position and the corresponding copper complexes were synthesized and characterized in this study. The influence of the substituent position on the copper complexes was investigated with various experimental and theoretical methods. The molecular structures of the copper complexes were examined in the solid state by single-crystal X-ray diffraction (SCXRD) and by density functional theory (DFT) calculations indicating a strong dependency on the substituent position compared to the systems substituted in the 2-position from the previous study. Further, the significantly different influence on the donor properties in dependency on the substituent position was analyzed with natural bond orbital (NBO) calculations. By the determination of the redox potentials, the impact on the electrochemical stabilization was examined. With regard to further previously analyzed guanidine quinoline copper complexes, the electrochemical stabilization was correlated with the charge-transfer energies calculated by NBO analysis and ground state energies, revealing the substituent influence and enabling a comparatively easy and accurate possibility for the theoretical calculation of the relative redox potential. Finally, the electron transfer properties were quantified by determining the electron self-exchange rates via the Marcus theory and by theoretical calculation of the reorganization energies via Nelsen's four-point method. The results gave important insights into the dependency between the ability of the copper complexes as entatic state model and the type and position of the substituent. [ABSTRACT FROM AUTHOR]

Copper‐catalyzed C─H oxygenation has drawn considerable attention in mechanistic studies. However, a comprehensive investigation combining radical pathways with a metal‐catalytic cycle is challenged by the intricate organic radicals and metallic intermediates. Herein, an online coupled EPR/UV–vis/near‐IR detecting method is developed to simultaneously monitor both reactive radical species and copper complex intermediates during the reaction. Focusing on copper‐catalyzed phenol oxygenation with cumene hydroperoxide, the short‐lived alkylperoxyl radical (EPR signal at g = 2.0143) as well as the unexpected square planar Cu(II)‐alkoxyl radical complex (near‐IR signal at 833 nm) are unveiled during the reaction, in addition to the observable phenoxyl radical in EPR, quinone product in UV–vis, and Cu(II) center in EPR. With a comprehensive picture of diverse intermediates evolving over the same timeline, a novel Cu(I)/Cu(II) proposed relay‐catalyzed sequential radical pathway. In this sequence, Cu(II) activates hydroperoxide through Cu(II)‐OOR into the alkylperoxide radical, while the reaction between Cu(I) and hydroperoxide leads to Cu(II)(•OR)OH with high H‐atom abstracting activity. These results provide a thorough understanding of the Cu(I)/Cu(II) relay catalysis for phenol oxygenation, setting the stage for mechanistic investigations into intricate radical reactions promoted by metallic complexes. [ABSTRACT FROM AUTHOR]

Correction for 'Addressing the gaps in homeostatic mechanisms of copper and copper dithiocarbamate complexes in cancer therapy: a shift from classical platinum-drug mechanisms' by Lydia W. Njenga et al., Dalton Trans., 2023, 52, 5823–5847, https://doi.org/10.1039/D3DT00366C. [ABSTRACT FROM AUTHOR]

Comprehensive Summary: Herein, we present a method for the homogeneous hydrogenation of nitroarenes to produce anilines using low catalyst loading (1 mo%) of copper N‐heterocyclic carbene complexes as the catalyst and ammonia borane as the source of hydrogen. A wide range of nitroarenes, featuring diverse functional groups, were selectively transformed into their corresponding primary aromatic amines with high yields. This process can be readily scaled up and exhibits compatibility with various sensitive functional groups, including halogen, trifluoromethyl, aminomethyl, alkenyl, cyano, ester, amide, and hydroxyl. Notably, this catalytic methodology finds application in the synthesis of essential drug compounds. Mechanistic investigations suggest that the in‐situ‐generated Cu‐H species may serve as active intermediates, with reduction pathways involving species such as azobenzene, 1,2‐diphenylhydrazine, nitrosobenzene, and N‐phenylhydroxylamine. [ABSTRACT FROM AUTHOR]

Pyridine-alkoxide (pyalk) ligands that support transition metals have been studied for their use in electrocatalytic applications. Herein, we used the pyalk proligands diphenyl(pyridin-2-yl)methanol ([H]PhPyalk, L1), 1-(pyren-1-yl)-1-(pyridin-2-yl)ethan-1-ol ([H]PyrPyalk, L2), 1-(pyridine-2-yl)-1-(thiophen-2-yl)ethan-1-ol ([H]ThioPyalk, L3), and 1-(ferrocenyl)-1-(pyridin-2-yl)ethan-1-ol ([H]FePyalk, L4) to synthesize CuII complexes that vary in nuclearity and secondary coordination sphere. Also, the proligand 1-(ferrocenyl)-1-(5-methoxy-pyridin-2-yl)ethan-1-ol ([H]FeOMePyalk, L5) was synthesized with a methoxy substituted pyridine; however, the isolation of a CuII complex ligated by L5 was not possible. Under variable reaction conditions, the pyalk ligands reacted with CuII precursors and formed either mononuclear or dinuclear CuII complexes depending on the amount of ligand added. The resulting complexes were characterized by single crystal X-ray diffraction, elemental analysis, and cyclic voltammetry. [ABSTRACT FROM AUTHOR]

A novel 1D coordination polymeric copper complex based on 4‐(4′‐nitrophenylhydrazono)‐5‐trifluoromethyl‐2,4‐dihydropyrazol‐3‐one was prepared and characterized spectroscopically and thermally and via X‐ray crystallographic investigation. The prepared copper‐based structure was proved to have a 1D coordination polymer. X‐ray studies showed that the polymeric copper complex was of octahedral geometry, the ligand acted as a bidentate ligand, and the nitro group attached to the ligand acted as a bridging group. The cytotoxic activities of the copper polymer were evaluated including against MCF‐7 cells (breast cancer cell line), HepG‐2 cells (hepatocellular carcinoma), and HCT‐116 cells (colon cancer cell line). The morphological alterations of the complex treated cells were investigated using an inverted microscope. The cell cycle and apoptosis were evaluated and reported. The copper polymer exhibited the best antitumor activity against HepG‐2 cells (35.22 ± 4.80 μM) while also causing a decline in the G2/M phase and a remarkable enhancement in the early apoptosis. [ABSTRACT FROM AUTHOR]

Infrared thermography (IRT), as a non-contact condition monitoring (CM) technique, measures the temperature distribution of machines and components to detect anomalous thermal behaviour. It is usually considered as a complementarytechnique and nowadays is used in a wide variety of industrial applications. In this paper, two commonly used criteria to assess the condition of machines based on the infrared thermography technique, ie absolute and relative temperature criteria, are represented. Then, the importance of the temperature trend in condition monitoring and fault diagnosis of machines and components is described. The ThermaITrend software, which was developed in the Condition Monitoring Unit, Smelting Department, Sarcheshmeh Copper Complex in Rafsanjan, Iran, is introduced and its most important and unique features are discussed. This software package helps thermographers toorganise thermal images and provides the temperaturetrends of machines and components that are under regular monitoring. Finally, some industrial case studies on the usefulness and applicability of the infrared thermography technique and the ThermaITrend software are reported. [ABSTRACT FROM AUTHOR]

In this study, a novel terpolymer was successfully obtained via the polycondensation polymerization of p-phenylenediamine and 2-aminothiazole with formaldehyde, employing dimethylformamide as a catalyst. The molar ratio of 1:1:2 for the reacting monomers yielded the newly devised p-phenylenediamine-2-aminothiazole-formaldehyde (P2ATF) terpolymer. Subsequently, the terpolymer was utilized as a ligand to form a copper complex by combining it with Cu2+ ions. To check the structure of both the terpolymer and its copper complex, a comprehensive array of techniques like Fourier-transform infrared spectroscopy, ultraviolet-visible spectroscopy, nuclear magnetic resonance, and elemental analysis were employed. Gel permeation chromatography was employed to determine the average terpolymer molecular weight. The surface characteristics of the terpolymer and its metal complex were investigated using scanning electron microscopy, providing insights into their morphology. Furthermore, the thermal properties of the terpolymer and its metal complex were examined using thermogravimetric analysis, allowing for an assessment of their thermal breakdown behavior. They also were subjected to biological evaluations against a diverse range of microorganisms, encompassing Escherichia coli, Staphylococcus aureus, Candida albicans, and Aspergillus niger. The findings from these assessments provide valuable insights into the potential biological activities of both the ligand and its complex, enhancing our understanding of their potential applications. [ABSTRACT FROM AUTHOR]

A new implementation of the internally contracted multireference coupled-cluster with singles and doubles (icMRCCSD) method is presented. The new code employs an efficient tensor contraction kernel and can also avoid full four-external integral transformations, which significantly extends the scope of the applicability of icMRCCSD. The new implementation is currently restricted to the simple case of two active electrons in two orbitals and also supports the computation of spin-adapted doublet and triplet coupled-cluster wavefunctions. This contribution describes the basic approach for the automated derivation of working equations and benchmarks the current code against efficient implementations of standard methods, such as single-reference coupled-cluster singles and doubles (CCSD) and internally contracted multireference configuration interaction (icMRCI). Run times for linearized variants of icMRCCSD are only twice as long as comparable CCSD runs and similar to those of the icMRCI implementation, while non-linear terms of more complete variants of icMRCCSD lead to an order of magnitude longer computation times. Nevertheless, the new code allows for computations at larger scales than it was possible previously, with less demands on memory and disk-space resources. This is exemplified by numerical structure optimizations and harmonic force field determinations of NC2H5 isomers and the singlet and triplet states of m-benzyne. In addition, the exchange coupling of a dinuclear copper complex is determined. This work also defines a new commutator approximation for icMRCCSD, which includes all terms that are also present in the single-reference CCSD method, thus yielding a consistent pair of single-reference and multireference coupled-cluster methods. [ABSTRACT FROM AUTHOR]

The mechanism of oxidation of phenols by tetrahedral copper(II)–halide complexes was investigated to demonstrate that phenols with an electron-withdrawing substituent are oxidized via a proton-transfer/electron-transfer (PTET) mechanism, whereas phenols with an electron-donating substituent involve a concerted proton/electron transfer (CPET) mechanism. The importance of the tetrahedral geometry of the metal centre as well as the effects of the halide ligands of the substrates were explored. [ABSTRACT FROM AUTHOR]

The Cu⋯Cu interactions, known as cuprophilicity, play a significant role in copper–chalcogenide functional materials. Three dinuclear copper chalcogenone complexes, [(L1CuI)2] (1), [(L2CuI)2] (2) and [Cu2(L3)4]PF6 (3), have been isolated and characterized. L1 = 1-(9-methyl anthracene)-2-isopropyl-benzimidazole-2-thione; L2 = 1-(9-methyl anthracene)-2-isopropyl-benzimidazole-2-selenone and L3 = 1-pyridine-2-isopropyl-imidazole-2-selenone, ligands and 1–3 were characterized by 1H NMR, 13C NMR, FT-IR, and SCXRD. Complexes 1 and 2 compress a four-membered strained ring system bridged by iodine, whereas 3 consists of a similar-four-membered ring core bridged by a selenium ligand. The Cu⋯Cu interactions in the crystal structures are observed (2.591 Å for 1, 2.576 Å for 2, and 2.523 Å for 3). The bridging ligand shows a key contribution to the Cu⋯Cu interactions. The density functional theory calculations also confirm the presence of d10⋯d10 interactions, which are predominantly covalent in nature. The computational study also shows the effect of the bridged ligands on the d10⋯d10 interactions and overall stability of the complexes, where complex 2 is the most stable followed by 1, and after that 3, although the d10⋯d10 interactions were the strongest in the case of 3. [ABSTRACT FROM AUTHOR]

The synthesis of phosphine acetylide amidinate stabilized copper(I) and gold(I) heterobimetallic complexes was achieved by reacting ligand [{Ph2PC≡CC(NDipp)2}Li(thf)3] (Dipp=2,6‐N,N′‐diisopropylphenyl) with CuCl and Au(tht))Cl, yielding the eight membered ring [{Ph2PC≡CC(NDipp)2}2Cu2] and the twelve membered ring [{Ph2PC≡CC(NDipp)2}2Au2]. {Ph2PC≡CC(NDipp)2}2Cu2] features a Cu2 unit, which is bridged by two amidinate ligands, served as a metalloligand to synthesize the heterobimetallic CuI/AuI complexes [{(AuX)Ph2PC≡CC(NDipp)2}2Cu2] (X=Cl, C6F5). In these reactions, the central ring structure is retained. In contrast, when the twelve membered ring [{Ph2PC≡CC(NDipp)2}2Au2] was reacted with CuX (X=Cl, Br, I and Mes), the reaction led to the rearrangement of the central ring structure to give [{(AuX)Ph2PC≡CC(NDipp)2}2Cu2] (X=Cl, Br, I and Mes), which feature the same the eight membered Cu2 ring as above. These compounds were also synthesized by a one‐pot reaction. The luminescent heterobimetallic complexes were further investigated for their photophysical properties. [ABSTRACT FROM AUTHOR]

Three novel heteroleptic mononuclear copper(I) complexes with a chelating diphosphine 1,2-bis-diphenylphosphinobenzene ligand (dppb) and various monoanionic bidentate LX-type ligand derivatives, 2-methyl-8-hydroxyquinolinate (Me-Q), 6-methyl-2-picolinate (Me-Pic) and 2-(2′-pyridyl)benzimidazolate (pbim), were prepared. The complexes are of formulae [Cu(Me-Pic)(dppb)] (3), [Cu(Me-Q)(dppb)] (2) and [Cu(pbim)(dppb)] (4). The structures of two of the compounds were unambiguously confirmed by a complete single-crystal X-ray diffraction study. The complexes were also characterized by UV-Vis spectroscopy. [ABSTRACT FROM AUTHOR]

Bioinspired by the active sites of multicopper oxidases (MCOs), bi/multinuclear copper complexes have attracted great attention in promoting catalytic activity for the oxygen reduction reaction (ORR). Herein, we report the preparation of a Cu–N–C electrocatalyst Cu-BPOZ@CNB-400 for efficient ORR, which was obtained by low temperature pyrolysis of a dinuclear 2,5-bis(2-pyridyl)-1,3,4-oxadiazole (BPOZ) copper complex loaded on a N-doped carbon support at 400 °C. Cu-BPOZ@CNB-400 exhibited a half-wave potential (E1/2) of 0.86 V vs. RHE for the ORR in 0.1 M KOH solution, which was significantly higher than that of the Cu-BPOZ@CNB-800 (E1/2 = 0.83 V) catalyst treated under high temperature (at 800 °C) and the control catalyst Cu-Phen@CNB-400 (E1/2 = 0.82 V) derived from low-temperature-treatment (at 400 °C) of a mononuclear phenanthroline-coordinated-Cu complex loaded on a N-doped carbon support. When Cu-BPOZ@CNB-400 was applied as the cathode catalyst in zinc–air batteries a maximum power density (Pmax) of 127 mW cm−2 could be achieved, demonstrating comparable catalyst performance to the commercial 20 wt% Pt/C (Pmax = 122 mW cm−2) and the control Cu-Phen@CNB-400 catalyst (Pmax = 105 mW cm−2) under similar experimental conditions. Low-temperature pyrolysis of dinuclear copper complexes on a carbon support improved the charge transfer efficiency, inhibited metal aggregation, and could produce highly dispersed Cu–N–C catalysts with dinuclear copper sites for promoting the 4e−-reduction selectivity of the ORR. It thus provides a cost-effective approach for the controllable fabrication of efficient ORR catalysts to be applied for energy conversion devices. [ABSTRACT FROM AUTHOR]

In the present era, the fixation of atmospheric CO2 is of significant importance and plays a crucial role in maintaining the balance of carbon and energy flow within ecosystems. Generally, CO2 fixation is carried out by autotrophic organisms; however, the scientific community has paid substantial attention to execute this process in laboratory. In this report, we synthesized two carbonato-bridged trinuclear copper(II) complexes, [Cu3(L1)3(μ3-CO3)](ClO4)3 (1) and [Cu3(L2)3(μ3-CO3)](ClO4)3 (2) via atmospheric fixation of CO2 starting with Cu(ClO4)2·6H2O and easily accessible pyridine/pyrazine-based N4 donor Schiff base ligands L1 and L2, respectively. Under very similar reaction conditions, the ligand framework embedded with the phenolate moiety (HL3) fails to do so because of the reduction of the Lewis acidity of the metal center, inhibiting the formation of a reactive hydroxide bound copper(II) species, which is required for the fixation of atmospheric CO2. X-ray crystal structures display that carbonate-oxygen atoms bridge three copper(II) centers in μ3syn–anti disposition in 1 and 2, whereas [Cu(HL3)(ClO4)] (3) is a mononuclear complex. Interestingly, we also isolated an important intermediate of atmospheric CO2 fixation and structurally characterized it as an anti–anti μ2 carbonato-bridged dinuclear copper(II) complex, [Cu2(L2)2(μ2-CO3)](ClO4)2·MeOH (2-I), providing an in-depth understanding of CO2 fixation in these systems. Variable temperature magnetic susceptibility measurement suggests ferromagnetic interactions between the metal centers in both 1 and 2, and the results have been further supported by DFT calculations. The catalytic efficiency of our synthesized complexes 1–3 was checked by means of catechol oxidase and phenoxazinone synthase-like activities. While complexes 1 and 2 showed oxidase-like activity for aerobic oxidation of o-aminophenol and 3,5-di-tert-butylcatechol, complex 3 was found to be feebly active. ESI mass spectrometry revealed that the oxidation reaction proceeds through the formation of complex–substrate intermediations and was further substantiated by DFT calculations. Moreover, active catalysts 1 and 2 were effectively utilized for the base-free oxidation of benzylic alcohols in the presence of air as a green and sustainable oxidant and catalytic amount of TEMPO in acetonitrile. Various substituted benzylic alcohols smoothly converted to their corresponding aldehydes under very mild conditions and ambient temperature. The present catalytic protocol showcases its environmental sustainability by producing minimal waste. [ABSTRACT FROM AUTHOR]

Superoxido copper complexes play an important role as usually short‐lived intermediates in biology and chemistry. The unusual stability of an end‐on superoxido copper complex observed in an oxygen‐enhanced atom transfer radical polymerization (ATRP) led to a detailed mechanistic investigation of the formation of [CuII(Me6tren)(O2⋅−)]+ (Me6tren=tris(2‐dimethyl‐aminoethyl)amine) under ambient conditions. The persistence of the superoxido copper complex could be explained by a reaction cycle including the peroxido complex [(Me6tren)2CuII2(O2)]2+ together with [CuI(Me6tren)(DMSO)]+ and [CuII(Me6tren)(OH)]+ in the overall reaction. [ABSTRACT FROM AUTHOR]

Pentafluorophenyl copper(I)–biarylsulfoxide complexes, existing as [Cu(C6F5)]4L2, both in solution and in the solid state, were prepared and thoroughly characterized. Subsequently, the photochemistry of the complexes was explored, showing inherent photoreactivity of the biarylsulfoxide moiety within the coordination sphere of the copper. Photoinduced cross-coupling reactions between the anthryl moiety of bis-anthracenylsulfoxide and pentafluorobenzene, and synthesis of Cu2O (cuprite), were demonstrated. [ABSTRACT FROM AUTHOR]

Mechanochromic luminescence materials have recently attracted increasing interest due to its promising applications, but the intensive inquiry of the mechanochromic luminescence mechanism is still insufficient. Herein, an in‐depth study of mechanochromic luminescent copper iodide complexes exhibiting ligand detachment and structural transformation is reported. The yellowish–green emissive CuI(dmpz) (dmpz = 2,6‐dimethylpyrazine) is ground into orange–red emissive CuI(dmpz)0.5 and the detailed structural transformation process is revealed by the thorough analysis of the crystalline structure before and after grinding. More importantly, new insight into the mechanochromic luminescence mechanism is proposed, that is, under the external force of grinding, the dmpz ligand detachment triggers the structural transformation from 1D chain to 2D network, which leads to the reduction of band gap energy and contraction of Cu─Cu bonds, together resulting in the red shift of luminescence ultimately. Moreover, the two complexes are also found to have thermochromic luminescence properties, attributing to their thermally activated delayed fluorescence process. The anti‐counterfeiting application of CuI(dmpz) is tentatively explored, demonstrating the favorable application prospect of CuI(dmpz). This study provides new insights involved in the mechanochromic luminescence mechanism of copper iodide complexes, and may provide a new understanding for rational molecular design and structural regulation of intelligent responsive luminescence. [ABSTRACT FROM AUTHOR]

In recent years, the global perspective of small molecule activation has directed the focus towards biomimetic oxidations. Phenoxazinone synthase and catechol oxidase, two vital metalloenzymes, have drawn the attention of the scientific community towards their catalytic performances. Different transition metal-based complexes have been investigated to mimic their activities, yet many factors related to their mechanistic aspects and structure–activity relationship still lack detailed investigation. To get better insights into these factors, two penta-coordinated cis-dichloro and dibromo Cu(II) complexes [Cu(L)Cl2] 1 and [Cu(L)Br2] 2 (where L = N,N-dimethyl-4,6-di(pyridin-2-yl)-1,3,5-triazin-2-amine) were synthesized and comprehensively characterized through various spectroscopic and analytical tools such as UV-vis, FT-IR, NMR, EPR and ESI-MS. The redox behaviour of ligands as well as both the copper complexes were analysed. The molecular structure of 1 and 2 was elucidated via single-crystal X-ray diffraction analysis and a distorted square pyramidal geometry was determined. The halogen atoms (Cl for 1 and Br for 2) are found to be coordinated in a cis fashion for better substrate attachment. Catalytic performances towards the oxidation of o-aminophenol (OAPH) and 3,5-di-tert-butylcatechol (3,5-DTBC) were investigated using UV-vis spectrophotometry. Significant kinetic parameters towards the catalytic activities for 1 and 2 were determined. In terms of OAPH oxidation ability, both complexes were found to be quite comparable, with 2 having greater catalytic performance (Kcat = 156.7 h−1) than 1 (Kcat = 124.5 h−1). However, 2 shows remarkably superior activity for 3,5-DTBC oxidation (Kcat = 367.8 h−1, ∼4.5 times) than 1 (Kcat = 82.2 h−1). The mass spectrometric investigation provides information about the probable mechanistic path towards the oxidation of both the substrates. Iodometric titration experiments were performed to identify H2O2 formation, which proves the involvement of molecular O2 during the catalytic oxidation. Overall, this study offers a detailed investigation on the significance of structural lability and their profound catalytic activities for biomimetic applications, which may open a new direction toward future advancements. [ABSTRACT FROM AUTHOR]

Fifteen new coordination binuclear compounds of copper(II) were synthesized based on substituted 4-tert-butyl-2,6-bis(N4-thiosemicarbazonyl)phenol (H3L1–3) ditopic ligands. The complexes were characterized using FT-IR spectroscopy, elemental analysis, MALDI-TOF analysis and X-ray diffraction studies highlighting the formation of dinuclear species with various bridging ligands between the two copper(II) atoms and in some cases the dimerization of these species into tetranuclear complexes. The antioxidant, antimicrobial and antifungal activities of ligands and their copper(II) coordination complexes have been investigated. In particular, the complexes show similar or better antimicrobial and antifungal properties than the drugs commonly used in this field. The structure–biological activity relationship is discussed based on the nature of the ligand and the copper salt used in the synthesis of the complexes. [ABSTRACT FROM AUTHOR]

Phenanthroline-based ligands with bulky aryl groups flanking the metal binding pocket enabled the synthesis and detailed investigation of ethylene complexes of copper(I), silver(I), and gold(I), including structural data of [{2,9-bis(2,4,6-triisopropylphenyl)-1,10-phenanthroline}M(C2H4)][SbF6] (M = Cu, Ag, Au), Additionally, a related copper(I)-ethylene complex with a highly fluorinated ligand is also reported. Gold(I) affects the ethylene moiety significantly as evident from the notable upfield coordination shifts of ethylene carbon signals in the NMR and lengthening of the ethylene C＝C bond length. Silver(I) forms the weakest bond with ethylene in this series of isoleptic, group 11 metal-ethylene complexes. Preliminary catalytic investigations underscore the potential of copper complexes, particularly those with weakly coordinating supporting ligands, as effective catalysts for C(sp3)–H functionalization through trifluoromethyl carbene insertion. [ABSTRACT FROM AUTHOR]

We synthesized a class of ligands that feature single (L1) and dual amine-bis(triazole) chelates (L2 with a 1,3-phenylene linker and L3 with a 1,5-naphthalene linker). Our findings which were derived from UV–Vis titrations, crystal structure analysis of relevant copper complexes, and DFT calculations indicate the formation of both mononuclear CuBr(L1) and dinuclear (μ-Ln)(CuBr)2 (Ln = L2 and L3) complexes. The catalytic activities of CuBr/Ln, in combination with TEMPO (2,2,6,6-tetramethylpiperidin-1-yl)oxyl) co-catalyst and NMI (N-methylimidazole) for aerobic alcohol oxidation, reveal the following activity trend: CuBr/L3 > CuBr/L2 > CuBr/L1. Furthermore, electrochemical data from in-situ generated CuBr complexes suggest that the higher catalytic performance of CuBr/L3 is attributed to the presence of less stable mixed-valence and more reducible Cu(I)-L3-Cu(II) species compared to Cu(I)-L2-Cu(II). This difference is a result of weaker σ interactions between Cu–Namine, larger bridging π systems, and a longer Cu···Cu distance in the presence of L3. Additionally, the catalyst system, CuBr/L3/TEMPO/NMI, efficiently promotes the aerobic oxidation of benzyl alcohol to benzaldehyde at room temperature in CH3CN with a high turnover frequency (TOF) of 38 h−1 at 1 h. [ABSTRACT FROM AUTHOR]

Background/Aims: The naturally occurring phenolic chemical curcumin (CUR), which was derived from the Curcuma longa plant, has a variety of biological actions, including antiinflammatory, antimicrobial, antioxidant, and anticancer activities. Curcumin is known for its restricted bioavailability due to its hydrophobicity, poor intestinal absorption, and quick metabolism. To boost the biological effects of these bioactive molecules, it is necessary to raise both their bioavailability and their solubility in water. Aim: The aim of this study is to synthesize and characterize hybrid organic-inorganic complexes of copper and cobalt, and to evaluate their antimicrobial potential against a range of pathogenic microorganisms. Methods: The synthesis of metal curcumin complexes (Cu-CUR and Co-CUR) was achieved by mixing curcumin with copper acetate monohydrate. The solid residue was isolated, filtered, and dried in an oven. X-ray diffraction analysis was used to identify the structure and phase of the prepared samples. FTIR spectra were recorded using a Shimadzu 2200 module. The antimicrobial activity of the prepared complexes was evaluated against four bacterial strains and two Candida species. The chemical materials were dissolved in DMSO to a final concentration of 20%, and the plates were incubated at 37°C for 24 hours. The results showed that the prepared complexes had antimicrobial activity against the tested microorganisms. Results: The study compared the Powder X-ray diffraction (XRD) patterns of prepared copper and cobalt complexes to pure curcumin, revealing new, isostructural complexes. The FTIR analysis showed that the Cu-CUR and Co-CUR complexes varied in their inhibitory effect against microorganisms, with Co-CUR being more effective. The results are consistent with previous studies showing the cobalt-curcumin complex was effective against various bacterial genera, with inhibition activity varying depending on the species and strains of microorganisms. Conclusion: Copper and cobalt curcumin complexes, synthesized at room temperature, exhibit high crystallinity and antimicrobial activity. Co-CUR, with its superior antibacterial potential, outperforms pure curcumin in inhibiting microbes. Further investigation is needed to understand their interaction mechanisms with bacteria and fungi. [ABSTRACT FROM AUTHOR]

Introduction: Casiopeina III-ia (CasIII-ia) is a mixed chelate copper (II) compound capable of interacting with free radicals generated in the respiratory chain through redox reactions, producing toxic reactive oxygen species (ROS) that compromise the viability of cancer cells, bacteria and protozoa. Due to its remarkable effect on protozoa, this study evaluated the effect of CasIII-ia on Leishmania mexicana amastigotes and its potential use as a treatment for cutaneous leishmaniasis in the murine model. Methods: We analyzed the leishmanicidal effect of CasIII-ia on L. mexicana amastigotes and on their survival in bone marrow-derived macrophages. Furthermore, we evaluated the production of ROS in treated parasites and the efficacy of CasIII-ia in the treatment of mice infected with L. mexicana. Results: Our results show that CasIII-ia reduces parasite viability in a dose-dependent manner that correlates with increased ROS production. A decrease in the size of footpad lesions and in parasite loads was observed in infected mice treated with the intraperitoneal administration of CasIII-ia. Conclusions: We propose CasIII-ia as a potential drug for the treatment of cutaneous leishmaniasis. [ABSTRACT FROM AUTHOR]

Three new copper(II) mononuclear complexes containing different organoselenium groups (1–3) were synthesized and characterized by the following techniques: elemental analysis, IR and UV‐Vis spectroscopies, electrochemical and conductimetric analysis, and mass spectrometry. Three new complexes, with substituents made in the para position of the aromatic portion of the N,N‐bis(2‐(phenylselanyl)ethyl)amine ligand: p‐OCH3 (1), p‐CH3 (2), and p‐Cl (3), were synthetized to compare with the already published complex (4), with no substituents. The ligand coordinates to the copper(II) center in a tridentate way with Se, N, Se as donor atoms. The hydrolytic activity in phosphate diester cleavage of the complexes was investigated using 2,4‐BDNPP as substrate. The modifications in the ligand are reflected in the difference between the catalytic and activation parameters, where the kcat values follow the order: 4 > 2 > 3 > 1. [ABSTRACT FROM AUTHOR]

Complex copper-based chalcogenides are a significant environmental-friendly functional material that has great application potential due to their interesting thermoelectric, photoelectric, optical, and other properties, as well as their ionic conductivity. Analysis of numerous studies shows that improving the application characteristics of these compounds is associated with manipulating their structure and composition. An effective solution for optimizing such processes requires their in-depth thermodynamic analysis, which requires reliable data on the fundamental thermodynamic characteristics of the corresponding compounds. This review summarizes the results of researches, including ours works, on the thermodynamic properties of copper chalcogenides with some p¹ -p³ elements. The majority of these works were carried out using various modifications of the electromotive force (EMF) method. Planning of experiments carried out by this equilibrium method of chemical thermodynamics and processing of their data is impossible without the presence of reliable data on phase equilibria. Taking this into account, in addition to thermodynamic data, the work also presents the solid-phase equilibria diagrams for a number of systems studied by the EMF method. The analysis showed that for the Cu-Tl-X, Cu-Ge(Sn)-X (X-S, Se, Te) and Cu-As(Sb, Bi)-S(Se) ternary systems there are mutually consistent data on the phase equilibria and thermodynamic functions of the ternary compounds. For the Cu-Tl-X and Cu-Sn-Se systems, the thermodynamic functions of ternary compounds are obtained by two modifications of the EMF method by determining the partial molar functions of two different components - copper and thallium (tin). The thermodynamic properties of copper chalcogenides with gallium, indium, and silicon have not been extensively researched, and the data that is available is inconsistent. [ABSTRACT FROM AUTHOR]

Five copper complexes (3a–e) stabilized by ring‐expanded back‐bond functionalized N‐heterocyclic carbene ligands (re‐NHCs) were produced in the glovebox by reacting free re‐NHC with CuI precursor. The potential of these re‐NHC‐Cu complexes as catalysts on the synthesis of mono‐ and di‐(1,4‐disubstituted‐1,2,3‐triazoles) by Cu‐catalyzed azide–alkyne cycloaddition (CuAAC) reactions was investigated. Various spectroscopic approaches were utilized to completely characterize the structures of the re‐Cu‐NHC complexes. Furthermore, density functional theory (DFT) calculations were carried out to get further insights into their molecular geometry and CuAAC reaction mechanism. The re‐NHC‐Cu complexes showed high activity on the CuAAC reaction in an open‐air atmosphere at rt. The Gibbs free energies as well as the optimized geometries of the intermediates and the transition states of the determining step of the reactions catalyzed by 3a, 3e, and 3b complexes were computed. Complex 3e was found to be the most efficient catalyst among these re‐NHC‐Cu complexes. Additionally, re‐Cu‐NHC complexes were investigated for their biological activities, including antiproliferative, antioxidant, AChE and TyrE inhibition, and antiparasitic activity. The results showed that the 3b, 3d, and 3e complexes possessed strong antiproliferative activity against human colon carcinoma (HCT‐116) and moderate cytotoxic activity against hepatocellular carcinoma (HepG‐2) cell lines. In addition, effective selective antileishmanial effects were observed for the 3e compound against both promastigotes and amastigotes stages of L. major with an IC50 value of 0.027 and 0.39 μM mL−1, respectively. These results demonstrate that these compounds are promising candidates for the treatment of colorectal cancer and leishmaniasis. [ABSTRACT FROM AUTHOR]

o‐Aminoazotoluene (OAT), capable of photoisomerization, and o‐vanillin, a potent comutagen, have been used to synthesize a new ligand, HL, [C6H4(CH3)N=NC6H3(CH3)N=CHC6H3(OH)(OCH3)], which, upon complexation with copper(II), results in a new copper(II) complex‐Cu(L)2, [Cu{C6H4(CH3)N=NC6H3(CH3)N=CHC6H3(OCH3)O}2]. Both HL and Cu(L)2 have been characterized by single‐crystal X‐ray diffraction measurements along with other analytical techniques, for example, IR spectroscopy, NMR spectroscopy, UV–Vis spectroscopy, elemental analysis and mass spectrometry. These compounds were tested with different in vitro anticancer assay as well as with in silico studies. A comparative study has been demonstrated on anticancer activity of HL and Cu(L)2 with the ligand HAZ, {C6H5N=NC6H4N=CHC6H3(OH)(OCH3)} and its Cu‐complex, [Cu(AZ)2, Cu{C6H5N=NC6H4N=CHC6H3(OCH3)O}2]. The sensing properties of HAZ, along with the synthesis and structural properties of both HAZ and Cu(AZ)2, have been reported by our group earlier. Cytotoxicity measurements on MCF7 cell lines show that Cu(L)2 and Cu(AZ)2 have higher anticancer activity than their corresponding ligands. The apoptotic effect of Cu‐complex was studied through nuclear fragmentation assay and AO/EB dual‐staining assay on MCF7 cell line. The IC50 value of Cu(L)2 in 0.01% DMSO/water after 24‐h treatment was found 4.2 μM, which is one of the lowest values with this response time compared to the other analogous anticancer compounds. Finally, we have evaluated the expression of hERα protein with respect to Cu‐complexes, and it was observed that Cu(L)2 caused more down‐regulation of hERα as compared to Cu(AZ)2. [ABSTRACT FROM AUTHOR]

Fluoroalkyl groups play an irreplaceable role in the field of pharmaceutical and agrochemical industry due to their unique properties. Based on this, it is crucial to effectively introduce fluoroalkyl groups into target molecules. In this review, we describe the synthesis of well‐defined fluoroalkyl zinc complexes and their applications in the fluoroalkylation of compounds. Different from the reactivities of copper fluoroalkyl complexes, fluoroalkyl zinc complexes often needed to be combined with copper or nickel catalysts when participating in fluoroalkylation reactions. From the perspective of reaction mechanism, the transfer of trifluoromethyl from zinc complexes to copper catalysts formed the highly active trifluoromethyl copper reagents, which can be directly used for the fluoroalkylation. In most cases, the desired target products were provided with excellent yields. [ABSTRACT FROM AUTHOR]

[Display omitted] Transition metal complexes of copper subgroup metals are actively studied objects for temperature sensors. Their luminescence arising from the 3ILCT, 3MLCT or 3CC excited states is characterized by emission in all ranges of visible spectra and high quantum yields. Due to the ability of the complexes to emit in a dual band mode, these complexes are attractive for the temperature sensing in the ratiometric mode. Dual emission of complexes is usually susceptible of the irregular changes in intensity of two emission bands during the temperature changes. This is an important and necessary property for the utilization of phosphors as ratiometric thermometers. The structures and emission properties of gold(i) and copper(i) complexes are considered with the aim to demonstrate the possibility to apply such complexes as ratiometric molecular luminescent thermometers for the remote control of the object's temperature. [ABSTRACT FROM AUTHOR]

The following series of copper(II) complexes based on di(o-tolyl)phosphinic acid (HL) and 1,10-phenanthroline (phen), 5-chloro-1,10-phenanthroline (Cl-phen), 4,7-dimethyl-1,10-phenanthroline (dmphen), 2,2′-bipyridine (bipy) is prepared and characterized: [Cu(OH)L]n (1), [Cu(phen)(H2O)L2] (2), [Cu(dmphen)(H2O)L2] (3), [Cu(Cl-phen)(H2O)L2] (4), [Cu(bipy)(H2O)L2] (5). According to the XRD data, the phosphinate anion L– exhibits a monodentate coordination in mononuclear complexes 2–5 and a bidentate-bridge coordination in the polymer complex 1. The cytotoxic activity of the ligands and complexes is studied using the A549 (carcinoma) and MRC5 (non-neoplastic fibroblasts) human lung cell lines. It is shown that the complexes exhibit pronounced dose-dependent cytotoxicity to these cell lines in the 1-50 µM concentration range. [ABSTRACT FROM AUTHOR]