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We report a series of structurally relevant copper phenanthroline complexes as pre-catalysts for highly selective electrocatalytic reduction of CO2 to C2 products using inexpensive carbon paper electrodes. The Cu complexes with non-substituted phenanthroline promote the production of ethylene with a high faradaic efficiency of 71.2%, while the one with pyridinium-functionalized ligands is more selective for ethanol. The C2 selectivity can be effectively tuned by increasing the number of coordinated phenanthrolines and remains high at a wide range of potentials. [ABSTRACT FROM AUTHOR]

This paper presents the development of cheap and selective Paper-based Analytical Devices (PADs) for selective Pd(II) determination from very acidic aqueous solutions. The PADs were obtained by impregnating two cm-side squares of filter paper with an azoic ligand, (2-(tetrazolylazo)-1,8 dihydroxy naphthalene-3,6,-disulphonic acid), termed TazoC. The so-obtained orange TazoC-PADs interact quickly with Pd(II) in aqueous solutions by forming a complex purple-blue-colored already at pH lower than 2. The dye complexes no other metal ions at such an acidic media, making TazoC-PADs highly selective to Pd(II) detection. Besides, at higher pH values, other cations, for example, Cu(II) and Ni(II), can interact with TazoC through the formation of stable and pink-magenta-colored complexes; however, it is possible to quantify Pd(II) in the presence of other cations using a multivariate approach. To this end, UV-vis spectra of the TazoC-PADs after equilibration with the metal ions solutions were registered in the 300–800 nm wavelength range. By applying Partial Least Square regression (PLS), the whole UV-vis spectra of the TazoC-PADs were related to the Pd(II) concentrations both when present alone in solution and also in the presence of Cu(II) and Ni(II). Tailored PLS models obtained with matrix-matched standard solutions correctly predicted Pd(II) concentrations in unknown samples and tap water spiked with the metal cation, making the method promising for quick and economical sensing of Pd(II). [ABSTRACT FROM AUTHOR]

The combination of electron-deficient viologen ligands with electron-rich POMs is a typical acceptor–donor system that has recently received much attention. Under solvothermal and hydrothermal conditions, by introducing three symmetric viologen ligands into POM-based hybrid materials, we successfully constructed four POMs–viologen inorganic–organic hybrid compounds, namely (1,3-bcbpy)2·(δ-Mo8O26) (1) (1,3-bcbpy·2Cl = 1,1′-bis(3-carboxybenzyl)-4,4′-bipyridine dichloride), {CoII(1,4-bcbpy)2(H2O)2[H2(β-Mo8O26)]}·2H2O·2CH2O (2), (1,4-bcbpy)2·(δ-Mo8O26)·2H2O (3) (1,4-bcbpy·2Cl = 1,1′-bis(4-carboxybenzyl)-4,4′-bipyridine dichloride, CH2O = formaldehyde), and {CuII(1,1-pmbby)2(H2O)[H2(β-Mo8O26)2]}·5H2O·C2H7N (4) (1,1-pmbby·2Cl = 1,1′-[1,4-phenylbis(methylene)]bis-(4,4′-bipyridine)dichloride, C2H7N = dimethylamine). These four compounds exhibit different fascinating structures, especially compound 4 is a typical metal–organic framework. Compounds 1–4 exhibit good discoloration behaviors under various external stimuli. For example, compounds 1–4 showed a positive response to the irradiation from a 300 W Xe lamp. When a positive voltage was applied to the ECD based on compounds 1–4, 1/2/3/4-ECD underwent a significant color conversion. What's more, compound 4 also showed obvious discoloration results after heating. In a word, 1–4 are multifunctional discoloration materials under different external stimuli. In addition, the coated filter paper prepared based on compound 3 can be used as a new printing material medium and can be successfully applied in erasable inkless printing and dual anti-counterfeiting. [ABSTRACT FROM AUTHOR]

A series of aminoquinoline derivatives with different N -alkyl substituents were synthesized and used in the development of paper-based fluorescent sensors. In aqueous solutions, the quinoline ligands show strong green fluorescence selectively upon binding to Zn2+ that is clearly observed by naked eyes under blacklight illumination. The paper-based sensors were prepared by depositing the amidoquinoline derivatives in wax-printed channels on filter paper. Developing of Zn2+ samples, deposited below the ligand spots, with an aqueous buffer solution creates green fluorescent lines suitable for distance measurement. The ligands with a tertiary amino group showed better-defined fluorescent lines than those of ligands containing primary and secondary amino groups. The length of the fluorescent lines increases linearly with the amounts of Zn2+ in the range of 2.5–80 nmol that can be easily determined by naked-eye observation or an image processing software. The increase in hydrophobicity of the ligands results in a wider dynamic concentration range of the detection. The paper-based sensor can accurately and conveniently quantify Zn2+ in drinking water, dietary supplement, and fertilizer samples. • New series of fluorescent ligands having variable hydrophobicity were synthesized. • Paper-based sensors for of Zn2+ with distance-based quantification were developed. • Dynamic range of Zn2+ quantification increases with hydrophobicity of the ligands. • The sensor is handy for quantitative analysis of Zn in water and food supplements. [ABSTRACT FROM AUTHOR]

In this work, four POM‐based compounds containing viologen ligands were synthesized, namely {CuII(tybipy)2(DMF)2[H2(β‐Mo8O26)]2} ⋅ 4 C2H7N (1), (Htybipy)2 ⋅ (β‐Mo8O26) (2) (tybipy⋅Br=1‐Thiophen‐3‐ylmethyl‐[4,4']bipyridinyl‐1‐ium bromide), [CuII(nibipy)2(4,4'‐bipy)] ⋅ (SiW12O40) (3), (Hnibipy)2 ⋅ (δ‐Mo8O26) (4) (nibipy⋅Cl=1‐(4‐Nitro‐benzyl)‐[4,4']bipyridinyl‐1‐ium chloride, 4,4'‐bipy=4,4'‐bipyridine). In compounds 1 and 3, Cu2+ and mixed organic ligands modify POM anions. On the other hand, 2 and 4 are supramolecular structures only containing ligands and anions. Under Xe lamp with filter (300‐400 nm) irradiation, these four compounds showed good photoresponse and photochromic ability, which can be used in mixed matrix films for visible UV detectors. Compounds 1–4 also have photoluminescence property and show good fluorescence quenching effect. A suspension of four compounds can be evenly spread on filter paper as inkless and erasable printing materials. Compounds 1 and 2 were also used as Hg2+ fluorescence detectors. The fluorescence intensity of 1 decreased by ca. 90 % when the concentration of Hg2+ increased to 40 mM. Moreover, we also prepared composites 1/2@Hg2+,1@Cu2+, 1@Co2+ by introducing 1/2 and Hg2+, Cu2+ and Co2+ to detection paper respectively, which can act as photochromic materials with features of fast color recovery. [ABSTRACT FROM AUTHOR]

This article explores the use of thioether-containing ligands in catalysis applications. Thioether ligands, which contain a sulfur atom, have traditionally been less considered due to their lower donor and acceptor character compared to phosphorus ligands. However, ligands with a low degree of oxidation and a combination of sulfur with another heteroatom have shown promise in generating interesting catalysts. The article provides examples of enantioselective and non-enantioselective reactions using thioether ligands and discusses the advantages of combining sulfur with another heteroatom. The paper is organized based on the type of heteroatom that accompanies the thioether function, such as phosphorus and nitrogen. Various catalytic systems involving thioether ligands for different organic transformations are discussed, including dihydroboration, cyclopropanation, silyl-hydrogen insertion, C-H functionalization, and C-H alkenylation. The ligands play a crucial role in enhancing the activity and selectivity of the catalysts, and they have been successfully applied to a wide range of substrates. Mechanistic studies have provided insights into the reaction pathways and the role of the ligands in facilitating the transformations. The article highlights the potential of thioether-functionalized ligands in metal-catalyzed reactions and suggests a promising future for sulfur in catalysis. [Extracted from the article]

[Display omitted] The efficacy of imaging-guided photodynamic therapy (PDT) is compromised by the attenuation of fluorescence and decline in reactive oxygen species (ROS) generation efficiency in the physiological environment of conventional photosensitizers, limited near-infrared (NIR) absorption, and high systemic cytotoxicity. This paper presents the synthesis of two cyclometalated Ir (III) complexes (Ir-thpy and Ir-ppy) by using a triphenylamine derivative (DPTPA) as the primary ligand and their encapsulation into an amphiphilic phospholipid to form nanoparticles (NPs). These complexes exhibit aggregation-induced emission features and remarkably enhanced ROS generation compared to Chlorin e6 (Ce6). Moreover, Ir-thpy NPs possess the unique ability to selectively target mitochondria, leading to depolarization of the mitochondrial membrane potential and ultimately triggering apoptosis. Notably, Ir-thpy NPs exhibit exceptional photocytotoxicity even towards cisplatin-resistant A549/DDP tumor cells. In vivo two-photon imaging verified the robust tumor-targeting efficacy of Ir-thpy NPs. The in vivo results unequivocally demonstrate that Ir-thpy NPs exhibit excellent tumor ablation along with remarkable biocompatibility. This study presents a promising approach for the development of multifunctional Ir-NPs for two-photon imaging-guided PDT and provides novel insights for potential clinical applications in oncology. [ABSTRACT FROM AUTHOR]

Antimicrobial photodynamic therapy offers significant benefits over standard antibiotic therapy in terms of rapid sterilization and resistance reduction. In this paper, a series of ruthenium complexes were designed and synthesized for antibacterial studies. [Ru(tpy)(dppz-R)Cl][PF6] (tpy = 2,2′:6′,2′′-terpyridine; dppz = dipyrido [3,2-a:2′,3′-c] phenazine; R = H, CH3, C(CH3)3, F, CF3, NO2, NH2 or CN), Ru1–Ru8 all showed superior in vitro antimicrobial effects under blue light irradiation. Ru2 has the best antimicrobial activity, with its inherent dark toxicity and photodynamic inactivation rapidly killing S. aureus without developing drug tolerance. Binding and damaging DNA as well as generating ROS may be its potential antimicrobial targets. Ru2 lacks a hemolytic effect on rabbit erythrocytes and has low phototoxicity against G. mellonella Larvae. In addition, Ru2 has been successfully used to treat skin wounds in mice infected with S. aureus. Therefore, Ru2 has shown great potential as a photodynamic antimicrobial agent against the threat of S. aureus infection. [ABSTRACT FROM AUTHOR]

The thiosemicarbazone containing polydentate Schiff base ligand is attracting interest in the field of coordination and biological application. The metal complexes exhibited stronger activity than free ligands against both cancer and bacteria due to the greater lipophilicity of complexes. These ligands possess hard and soft base S-N-O coordinating sites, which participate in chelation simultaneously with metal ions. These ligands could coordinate to transition metals through various modes. The paper focuses on the coordination of the thiosemicarbazone Schiff base ligands with nickel, palladium, and platinum metal ions to generate biologically active complexes. Both the ligands and the metals have strong biological properties. So, the most important biological activities, particularly anticancer and antibacterial are considered in the study. There is a lot of scientific data available regarding Schiff base ligands and their transition metal complexes. Still, our study collects more informative data, from the past to date, of Schiff base thiosemicarbazone ligands and their complexes. The nickel complex showed higher activity than cisplatin against Hela cancer cell, HCT 116 with IC50 of 7.9 ± 0.2 µM and 10.1 ± 0.09 µM respectively. These types of compounds could be used as potential medicinal agents in the near future against various lethal diseases. [ABSTRACT FROM AUTHOR]

The tremendous importance of dirhodium paddlewheel complexes for asymmetric catalysis is largely the result of an empirical optimization of the chiral ligand sphere about the bimetallic core. It was only recently that a H(C)Rh triple resonance 103Rh NMR experiment provided the long‐awaited opportunity to examine – with previously inconceivable accuracy – how variation of the ligands impacts on the electronic structure of such catalysts. The recorded effects are dramatic: formal replacement of only one out of eight O‐atoms surrounding the metal centers in a dirhodium tetracarboxylate by an N‐atom results in a shielding of the corresponding Rh‐site of no less than 1000 ppm. The current paper provides the theoretical framework that allows this and related experimental observations made with a set of 19 representative rhodium complexes to be interpreted. In line with symmetry considerations, it is shown that the shielding tensor responds only to the donor ability of the equatorial ligands along the perpendicular principal axis. Axial ligands, in contrast, have no direct effect on shielding but may come into play via the electronic cis ${cis}$ ‐effect that they exert onto the neighboring equatorial sites. On top of these fundamental interactions, charge redistribution within the core as well as the electronic trans ${trans}$ ‐effect of ligands of different donor strengths is reflected in the recorded 103Rh NMR shifts. [ABSTRACT FROM AUTHOR]

A novel multifunctional coordination polymer {[Zn(HCOO) (bcbpy)Cl]·H 2 O} n (1) with multiple colour-changing has been synthesized from Zn(NO 3) 2 ·6H 2 O, and viologen ligand 1,1′-bis-((3-carboxylatobenzyl)-4,4′-bipyridinium) dichloride (H 2 bcbpy·2Cl). In coordination polymer (CP) 1 , bcbpy ligands bridge Zn2+ cations to form a 1D wave-like chain. CP 1 exhibited photochromic properties under xenon lamp and blue light irradiation while obtaining a structurally stable light product 1T. CP 1 thermochromic properties can also be observed during heating. 1 showed photo-controlled fluorescence properties during color rendering and decolorization, and its properties were studied. Interestingly, CP 1 can be deposited in filter paper by coating it with a solution of H 2 O. The filter paper can be used as a printing medium without ink. [Display omitted] • CP 1 was synthesized using viologen ligand 1,1′-bis-((3-carboxylatobenzyl)-4,4′-bipyridinium) dichloride (H 2 bcbpy·2Cl). • CP 1 exhibited photochromic properties under xenon lamp and blue light irradiation. • CP 1 obtaining a structurally stable light product 1T after irradiation. • CP 1 can be used as a good ink-free printing medium. [ABSTRACT FROM AUTHOR]

Cisplatin-based metallodrugs are traditionally utilized as anticancer agents. Nonetheless, these drugs have adverse effects on normal tissues since cisplatin eliminates the body amid cancerous growth cells by destroying the sequence of genomic DNA. As a result, the metallodrug structure demonstrated numerous antagonistic behaviours to the malignant tumour development system associated with nucleic acid G-quadruplex. This paper systematically explored the development of successful procedures and competent anticancer drugs that expressly collaborate, resolve, or divide G4 structures. In the therapeutic domain, we highlighted the cutting-edge G4-metallo-structures, their interface mechanisms, and the potential for use as anticancer medicines. Furthermore, this paper also describes the methodologies utilized to discriminate the binding capacity between G-quadruplex and metallo-structures. This review will help to create metallodrugs from the most significant electrical supplementary design specification to a progressively logical bio-science level. [ABSTRACT FROM AUTHOR]

The C═N bond is a critical structural piece of many N-donor ligand scaffolds and is central to the properties and reactivity of important coordination complexes. For example, C═N units play a key role in the "redox non-innocence" of α-diimine complexes and in making charge-transfer excited-state character available to complexes of N-heterocyclic ligands such as bipyridine. In N-heterocycles like pyridine, benzannulation can be used to extend the conjugated C═N-containing π-system to quinoline (2,3-benzopyridine) to acridine (2,3-benzoquinoline). This stabilizes the lowest unoccupied molecular orbital of the molecule and boosts its electron-accepting properties, but the position of the benzannulation matters. For example, phenanthridine (3,4-benzoquinoline), an asymmetric isomer of acridine, bears a similarly electronically accessible extended π-system but with a more chemically isolated "imine-like" C═N moiety. This award paper presents an overview of our work investigating the impact of such site-selective benzannulation on the chemistry and properties of phenanthridine as a molecule and ligand. [ABSTRACT FROM AUTHOR]

The diversity of catalytic activities and antioxidant properties of cerium oxide nanoparticles (CeO2 NPs) makes them promising materials for the theranostics of various diseases, especially those caused by disturbances in free radical homeostasis in living systems. Despite the fact that the functionalisation of nanoparticles' surface plays a critical role in nanomedicine applications, the effect of different coatings on their enzyme-like behaviour and antioxidant properties is still poorly understood, which limits the biomedical application of CeO2 NPs. This paper reports on the effect of low and high molecular weight biocompatible ligands on the SOD-like activity and radical scavenging properties of CeO2 NPs, which was analysed using a phosphate-rich medium resembling a natural environment. The results obtained show that these ligands modulate the SOD-like properties of CeO2 NPs as follows. Citrate and polysaccharide (maltodextrin and dextran) surface coatings increase the SOD-like activity of CeO2 NPs by an average of 2.2 times, and the protein corona (γ-globulin, γ-IgG) increases this activity by an average of 1.8 times. Citrate-coated CeO2 NPs and CeO2 nanoparticles modified with polysaccharide molecules are more effective SOD mimetics than CeO2@γ-IgG NPs. The SOD-like activity of phosphatidylcholine-coated CeO2 and CeO2@γ-IgG NPs is due to the combined action of nanoscale CeO2 and ligands. The antioxidant activity of CeO2 NPs after their modification with different ligands with respect to alkyl peroxyl radicals is multidirectional. Unexpectedly, citrate-, maltodextrin- and dextran-coated CeO2 NPs are more effective antioxidants than bare CeO2 NPs. CeO2 NPs modified with phosphatidylcholine or γ-IgG exhibited less radical-scavenging ability than bare CeO2 nanoparticles. Thus, common biocompatible ligands are able to regulate the biochemical activity of CeO2 NPs. [ABSTRACT FROM AUTHOR]

The paper deals with the synthesis of a series of cationic [Pt(ppz)2(N^N)]2+ complexes containing deprotonated 1‐phenyl‐1H‐pyrazole as cyclometallating (C^N) ligands and α‐diimines (N^N) in the form of water‐soluble salts with OTf− (trifluoromethanesulfonate) counter ions. These complexes were obtained from cis‐[Pt(ppz)2Cl2] through chloride ligands substitution with α‐diimines. The complexes were identified by means of NMR spectroscopy and their molecular structures were confirmed by X‐ray crystallography. The photophysical properties of these complexes were studied in detail. These complexes showed strong luminescence in MeOH/EtOH 1 : 1 glasses at 77 K but were almost non‐emitting in MeCN solutions at room temperature. Their emission properties were compared to analogues IrIII complexes. [ABSTRACT FROM AUTHOR]

Simple Summary: Breast cancer is a highly malignant tumor that threatens the health of women worldwide, with extremely high morbidity and mortality. The study of the related genes that affect the occurrence and development of breast cancer can provide more clinical evidence for its prevention and treatment. Peroxisome proliferators-activated receptors are a class of ligand-dependent nuclear receptor transcription factors discovered in 1990 that can regulate the transcription of many genes involved in various cellular physiological processes. The dysregulation of these physiological processes is highly correlated with the occurrence of various diseases, including malignant tumors. Additionally, a large number of reports have indicated that the transcriptional regulation function of peroxisome proliferator-activated receptors and its abnormal expression are related to breast cancer. This article summarizes the role of peroxisome proliferator-activated receptors and their different ligands in the progression of breast cancer since their discovery by searching relevant literature. The purpose of this review is to regard peroxisome proliferators-activated receptors as the new targets for the prevention of breast cancer and to incorporate their ligands into the new evidence for clinical drug combination therapy, especially for high-recurrence triple-negative breast cancer. Breast cancer is a malignant tumor with high morbidity and lethality. Its pathogenesis is related to the abnormal expression of many genes. The peroxisome proliferator-activated receptors (PPARs) are a class of ligand-dependent transcription factors in the nuclear receptor superfamily. They can regulate the transcription of a large number of target genes, which are involved in life activities such as cell proliferation, differentiation, metabolism, and apoptosis, and regulate physiological processes such as glucose metabolism, lipid metabolism, inflammation, and wound healing. Further, the changes in its expression are associated with various diseases, including breast cancer. The experimental reports related to "PPAR" and "breast cancer" were retrieved from PubMed since the discovery of PPARs and summarized in this paper. This review (1) analyzed the roles and potential molecular mechanisms of non-coordinated and ligand-activated subtypes of PPARs in breast cancer progression; (2) discussed the correlations between PPARs and estrogen receptors (ERs) as the nuclear receptor superfamily; and (3) investigated the interaction between PPARs and key regulators in several signaling pathways. As a result, this paper identifies PPARs as targets for breast cancer prevention and treatment in order to provide more evidence for the synthesis of new drugs targeting PPARs or the search for new drug combination treatments. [ABSTRACT FROM AUTHOR]

We report heteroleptic ruthenium complexes of terpyridine (tpy) ligands with directly linked carboxylic acid anchors. These complexes feature methyl or methoxy‐substituted 4′−Phtpy as donor ligands. We prepared these heteroleptic complexes from the ruthenium (II) precursor via a milder route to preclude the homoleptic complex formation. The donor−acceptor arrangement of tpy ligands in these ruthenium complexes renders visible light absorption giving metal and ligand‐to‐ligand charge transfer excitations at c.a. 490 nm. We evaluate the effect of the tpy donor substituents on the light‐harvesting ability in Dye‐Sensitized Solar Cells (DSSCs) and compare their photosensitizing ability with heteroleptic complexes bearing phenyl spacer at the acceptor end. Further, scrutinizing their photovoltaic performance, we studied their electron transfer kinetics in DSSCs using electrochemical impedance spectroscopy. This paper presents the structure‐photosensitization relationship of these heteroleptic ruthenium complexes through a combined experimental and computational approach. [ABSTRACT FROM AUTHOR]

This paper provides a general overview of palladium complexes incorporating numerous multidentate azo-imine ligands, their structural diversity, synthetic protocol, interesting properties such as redox properties, biological activity and their further application on C – N coupling reactions, C – C cross-coupling reactions (e.g., Suzuki and Heck) and catalytic activity on different organic transformations. A detailed literature survey revealed that no brief review has yet been published on the azo-azomethine-based palladium complex. Therefore, the present review incorporates the research undertaken on the synthetic strategies and coordinating behaviour of various azo-imine ligands with palladium metal centre and a few important properties of metal complexes. [ABSTRACT FROM AUTHOR]

Constructing high-performance glucose sensors is of great significance for the prevention and diagnosis of diabetes, and the key is to develop new sensitive materials. In this paper, a series of Ni2Co1-L MOFs (L = H2BPDC: 4,4′-biphenyldicarboxylic acid; H2NDC: 2,6-naphthalenedicarboxylic acid; H2BDC: 1,4-benzenedicarboxylic acid) were synthesized by a room temperature stirring method. The effects of metal centers and ligands on the structure, compositions, electrochemical properties of the obtained Ni2Co1-L MOFs were characterized, indicating the successful preparation of layered MOFs with different sizes, stacking degrees, electrochemical active areas, numbers of exposed active sites, and glucose catalytic activity. Among them, Ni2Co1-BDC exhibits a relatively thin and homogeneous plate-like morphology, and the Ni2Co1-BDC modified glassy carbon electrode (Ni2Co1-BDC/GCE) has the highest electrochemical performance. Furthermore, the mechanism of the enhanced glucose oxidation signal was investigated. It was shown that glucose has a higher electron transfer capacity and a larger apparent catalytic rate constant on the Ni2Co1-BDC/GCE surface. Therefore, tunable non-enzymatic glucose electrochemical sensing was carried out by regulating the metal centers and ligands. As a result, a high-sensitivity enzyme-free glucose sensing platform was successfully constructed based on the Ni2Co1-BDC/GCE, which has a wide linear range of 0.5–2899.5 μM, a low detection limit of 0.29 μM (S/N = 3), and a high sensitivity of 3925.3 μA mM−1 cm−2. Much more importantly, it was also successfully applied to the determination of glucose in human serum with satisfactory results, demonstrating its potential for glucose detection in real samples. [ABSTRACT FROM AUTHOR]

LiGd(MoO 4) 2 has been investigated due to its optoelectronic applications, especially for development of light-emitting diodes. In the present paper, LiGd(MoO 4) 2 single crystals grown by Czochralski method was studied in terms of structural and temperature dependent optical properties. X-ray diffraction analysis showed that the crystal crystallizes in a single phase tetragonal structure. Raman spectrum exhibited six distinguishable peaks around 207, 319, 397, 706, 756 and 890 cm−1. These peaks correspond to vibrational modes of free rotation, symmetrical stretching, symmetric bending, antisymmetric stretching and antisymmetric bending of (MoO 4)2− tetrahedron. Infrared transmittance spectrum had eight minima around 2114, 2350, 2451, 2854, 2929, 2960, 3545 and 3578 cm−1 which are due to multiphonon absorptions. Spectral change of transmittance curves at various temperature between 10 and 300 K was utilized to elucidate temperature effect on absorption characteristics. Optical band gap of the material was found using Tauc and spectral derivative methods. The band gap value was obtained as 3.09 eV at room temperature and this value increased to 3.22 eV with decreasing temperature down to 10 K. The detailed analysis on the temperature dependency of the band gap was applied by Varshni model. The band gap at 0 K and change of rate of the band gap were estimated as 3.23 eV and −1.45 × 10−3 eV/K, respectively. Room temperature photoluminescence spectrum of the crystal presented a peak around 709 nm which corresponds to red light emission. LiGd(MoO 4) 2 is a potential candidate for optoelectronic devices emitting red light. [ABSTRACT FROM AUTHOR]

Transition metal-catalyzed reactions invariably include steps where ligands associate or dissociate. In order to obtain reliable energies for such reactions, sufficiently large basis sets need to be employed. In this paper, we have used high-precision multiwavelet calculations to compute the metal–ligand association energies for 27 transition metal complexes with common ligands, such as H2, CO, olefins, and solvent molecules. By comparing our multiwavelet results to a variety of frequently used Gaussian-type basis sets, we show that counterpoise corrections, which are widely employed to correct for basis set superposition errors, often lead to underbinding. Additionally, counterpoise corrections are difficult to employ when the association step also involves a chemical transformation. Multiwavelets, which can be conveniently applied to all types of reactions, provide a promising alternative for computing electronic interaction energies free from any basis set errors. [ABSTRACT FROM AUTHOR]

The π⋯π interactions in spin crossover (SCO) complexes can be used as an important means to fine-tune the spin transition behaviors. In this paper, three novel isostructural 2D Hofmann-type frameworks, [Fe(ppo)2M(CN)4] (1, M = Pt2+; 2, M = Pd2+; 3, M = Ni2+) have been successfully synthesized by judiciously choosing a large conjugated molecule, 2-(2-pyridyl)-5-(4-pyridyl)-1,3,4-oxadiazole (ppo) as the axial ligand. Single crystal X-ray crystallography analysis showed that there are different π⋯π interactions between the axial ppo ligands in 1–3. Variable temperature magnetic susceptibility studies revealed that 1 and 3 displayed incomplete and gradual SCO behaviors with T1/2 = 94 and 78 K, respectively, while 2 stayed in a high-spin state in the measured temperature range. The stronger π⋯π interactions between the conjugated ppo ligands observed in 1 and 3 than those in 2 may result in their different magnetic behaviors. [ABSTRACT FROM AUTHOR]

This paper covers nineteen Pt(II) complexes of the composition Pt(η3-X1X2X3)(PR3), (X = N1, N2, N3; S1, S2, S3; or Te1, Te2, Te3). These complexes crystallized in three crystal classes: triclinic (eleven examples), monoclinic (six examples), and orthorhombic (two examples). Each tridentate ligand creates two metallocyclic rings with common N2, S2, or Te2 donor ligands of the types N1C2N2C2N3, N1C2N2NC2N3, S1C2S2C2S3, S1C3S2C3S3, and Te1CNTe2NCTe3. The homotridentate ligand with monodentate PR3 ligand builds up a distorted square planar geometry about Pt(II) atoms. The degree of distortion ranges from 0.029 to 0.092, and the reason for the distortion is discussed. There is an example that contains two crystallographically independent molecules within the same crystal. This is a classic example of distortion isomerism. [ABSTRACT FROM AUTHOR]

Cancer stem cells (CSCs) are a small proportion of tumor cells with great tumorigenicity, self‐renewal ability, and intrinsic resistance to conventional and targeted cancer therapy; thus, targeting CSC is becoming an emerging cancer treatment. In this paper, five novel copper (II) complexes [Cu(OH‐PIP)(Tyr)(H2O)]PF6 (1), [Cu(m‐OH‐PIP)(Gly)]NO3·2.25H2O (2), [Cu(Cl‐PIP)(Gly)Br] (3), [Cu(F‐PIP)(Tyr)Cl] (4), and [Cu(F‐PIP)(Phe)Br] (5) have been synthesized and characterized by infrared spectroscopy and single crystal X‐ray diffraction analysis. All the complexes were screened for their in vitro cytotoxicity activity against a panel of human breast cancer cells (CAL‐51, MDA‐MB‐231, and MCF‐7), human liver cancer cells (HepG 2, SMMC‐7721) and human pancreatic cancer cells (PANC‐1) using MTT assay. They have potential proliferative inhibition for all the tested cancer cell lines, especially the triple‐negative breast cancer (TNBC) CAL‐51 cells are inhibited significantly with IC50 values ranging from 0.11 to 2.35 μM. Cellular functional assays showed that representative complexes 1 and 5 could trigger apoptosis, evidenced by Hoechst 33258 staining, flow cytometry assays, and the alteration of Bax, Bcl‐2, Caspase‐3, and PARP levels. In addition, they dramatically suppressed colony and mammosphere formation, inhibited cancer cell stemness and migration, and reversed epithelial–mesenchymal transition (EMT) progression in CAL‐51 cells, indicating their great potential as anti‐CSC agents for therapy of TNBC. [ABSTRACT FROM AUTHOR]

From its very beginnings in the 1970s, rap music has reflected the profound disenfranchisement of African Americans living in the nation's neglected and abandoned inner cities. Rap was only one aspect of hip hop that emerged in the South Bronx in that time period--along with graffiti and breakdancing, among others. Rap could be playful, catchy, sexy, and humorous, but it also intoned a forceful cultural critique of ongoing and horrendous disparities facing Black communities, including police violence, systemic inequity in the criminal justice system, housing discrimination, and educational disparity. This paper focuses on a lyrical and thematic analysis of the work of two hip hop artists--one legendary artist from the 1990s and one contemporary hip hop artist who is already making a sizable mark on the genre--as they reflect on and unpack the sociohistorical contexts of their times. The paper unpacks the lyrics of our two hip hop artists through a theoretical lens that evokes oppositional cultures or cultures of resistance within distinct social locations or cultural formations--a nuanced response to appalling structural disparity then and now. [ABSTRACT FROM AUTHOR]

[MoV2 O2S2]2+-based thiosemicarbazone complexes appear as very promising molecules for biological applications due to the intrinsic properties of their components. This paper deals with the synthesis and characterization of six coordination complexes obtained by the reaction of [MoV2 O2S2]2+ clusters with bisthiosemicarbazone ligands that contain flexible or rigid spacers between the two thiosemicarbazone units. Interestingly, structural characterization by single-crystal X-ray diffraction, MALDI-TOF MS technique and NMR spectroscopy revealed that the nuclearity of the complex is controlled by the nature of the spacer between the thiosemicarbazone units. Binuclear complexes, namely [MoV2 O2S2(L1-3)], are isolated with flexible spacers while tetranuclear complexes [(MoV² O2S2)2(L4-6)2] are formed when the bisthiosemicarbazone ligands are built on rigid spacers. [ABSTRACT FROM AUTHOR]

This paper presents the synthesis and structural characterization of a series of new ruthenium(II) complexes 1–7, with the general formula mer-[RuL3(N–N)Cl]Cl, where L is 2,2′:6′,2′′-terpyridine (tpy) or 4′-(4-chlorophenyl)-2,2′:6′,2′′-terpyridine (Cl-Ph-tpy) and N–N is o-benzoquinonediimine (o-bqdi), 2,3-naphthoquinonediimine (nqdi), 4,4′-dimethyl-2,2′-bipyridine (dmbpy) or 2,2′-bipyridine-4,4′-dicarboxylic acid (dcbpy). The kinetic results showed that the ligand substitution reactions of new Ru(II)-polypyridyl complexes with biomolecules were affected by different substituents and the aromaticity of meridional tridentate and bidentate spectator ligands as well as by the nature of the entering nucleophile. The reactivity of the complexes increases in the order: dmbpy < dcbipy < nqdi < o-bqdi. In addition, quantum chemical calculations were performed to support the interpretation and discussion of the experimental data. Furthermore, combining ethidium bromide (EB) and Hoechst 33258 (2-(4-hydroxyphenyl)-5-[5-(4-methylpiperazine-1-yl)benzimidazo-2-yl]-benzimidazole) fluorescence assay results implied that 1–7 might interact with calf thymus DNA through partial intercalation and/or minor groove binding. The human serum albumin (HAS)-fluorescence binding studies involving the site markers, eosin Y, as a marker for site I of subdomain IIA, and ibuprofen, as a marker for site II of subdomain IIIA, showed that Ru(II) compounds bind to both sites with moderately strong affinity (Kb = 104–106 M−1). Moreover, these DNA/HSA experimental results were confirmed by molecular docking. Complexes 2, 5 and 6 exerted good to strong and highly selective cytotoxic activity against breast adenocarcinoma (MDA-MB 231), colorectal carcinoma (HCT116) and cervix adenocarcinoma (HeLa). Depending on their structure and cell line, the complexes acted differently in terms of their influence on autophagy, the cell cycle and the engaged apoptotic pathway. [ABSTRACT FROM AUTHOR]

This paper describes the synthesis and catalytic testing of a palladium complex with a 5-membered chelating [N,O] ligand, derived from the condensation of 2,6-diisopropylphenyl aniline and maple lactone. This catalyst was active towards the Suzuki-Miyaura cross-coupling reaction, and its activity was optimised through the selection of base, solvent, catalytic loading and temperature. The optimised conditions are mild, occurring at room temperature and over a short timescale (1 h) using solvents considered to be 'green'. A substrate scope was then carried out in which the catalyst showed good activity towards aryl bromides with electron-withdrawing groups. The catalyst was active across a broad scope of electron-donating and high-withdrawing aryl bromides with the highest activity shown for weak electron-withdrawing groups. The catalyst also showed good activity across a range of boronic acids and pinacol esters with even boronic acids featuring strong electron-withdrawing groups showing some activity. The catalyst was also a capable catalyst for the cross-coupling of aryl chlorides and phenylboronic acid. This more challenging reaction requires slightly elevated temperatures over a longer timescale but is still considered mild compared to similar examples in the literature. [ABSTRACT FROM AUTHOR]

Covalent triazine frameworks (CTFs) based on polydentate ligands are highly promising supports to anchor catalytic metal complexes. The modular nature of CTFs allows to tailor the composition, structure, and function to its specific application. Access to a broad range of chelating building blocks is therefore essential. In this respect, we extended the current available set of CTF building blocks with new nitrile-functionalized N-heterocyclic ligands. This paper presents the synthesis of the six ligands which vary in the extent of the aromatic system and the denticity. The new building blocks may help in a rational design of enhanced support materials in catalysis. [ABSTRACT FROM AUTHOR]

In this paper, Grubbs- and Hoveyda–Grubbs-type olefin metathesis catalysts featuring N-cyclopentyl/N'-mesityl backbone-substituted N-heterocyclic carbene (NHC) ligands were synthesized. Their propensity to promote the alternating ring-opening metathesis copolymerization (ROMP) of norbornene (NBE) with cyclooctene (COE) or cyclopentene (CPE) was evaluated and compared to that shown by analogous N-cyclohexyl complexes. High degrees of chemoselectivity were achieved in both copolymerizations. The presence of the N-cyclopentyl substituent allowed for the achievement of up to 98% and 97% of alternating diads for NBE-COE and NBE-CPE copolymers, respectively, at low comonomer ratios. Density functional theory (DFT) studies showed that both the sterical and electronic effects of NHC ligands influence catalyst selectivity. [ABSTRACT FROM AUTHOR]

• The solubility of four compounds was investigated. • The experimental solubility data were correlated by thermodynamic models. • The values of HSPs for metal complexes were predicted. • The optimal mixing ratios of the two metal complexes in the two mixed solvents were predicted. In this paper, two novel five-coordinated copper(II) metal complexes, [2,6-(ArN = CMe) 2 C 5 H 3 NCuCl 2 ] (Ar = 2-EtC 6 H 4 , L 1 CuCl 2 ; Ar = 4-EtC 6 H 4 , L 2 CuCl 2), bearing bulky 2,6-bis[1-(2-ethylphenylimino)ethyl]pyridine ligands L 1 (L 1 = 2,6-(ArN = CMe) 2 C 5 H 3 N, Ar = 2-EtC 6 H 4), 2,6-bis[1-(4-ethylphenylimino)ethyl]pyridine ligands L 2 (L 2 = 2,6-(ArN = CMe) 2 C 5 H 3 N, Ar = 4-EtC 6 H 4) have been synthesized and characterized, and the thermodynamic properties of these complexes are reported in a variety of mono-solvents. The copper(II) metal complexes based on bis(imino)pyridine are widely used in catalysis, photoelectric material, biopharmaceuticals and other fields. In this paper, the solubility of L 1 and L 2 in four solvents, the solubility of L 1 CuCl 2 in four solvents and the solubility of L 2 CuCl 2 in five solvents were studied by static analysis. The solubility of these compounds was investigated in a certain temperature range to provide data to support the selection of optimal solvents for organic reactions, coating and crystallization separations. Hansen solubility parameters (HSPs) were used to explain the dissolution behavior of solutes and were found to be consistent with experimentally measured results. Moreover, the values of HSPs for L 1 CuCl 2 and L 2 CuCl 2 lacking Cu data were simulated by the Hansen Solubility Parameters in Practice (HSPiP) software, which allowed the prediction of solvents with good dissolution behavior. The values of total solubility parameter of Hildebrand (δ) for L 1 CuCl 2 and L 2 CuCl 2 are 24.5 and 23.0, respectively. Besides, solubility properties of L 1 CuCl 2 and L 2 CuCl 2 in two solvent mixtures at different percentages were predicted. In addition, seven thermodynamic models were used to correlate the solubility data. For L 1 and L 2 , Polynomial models fit better with an average absolute relative deviation (ARD) less than 1 %; for L 1 CuCl 2 and L 2 CuCl 2 , Polynomial model fits best (ARD < 1 %). In addition, the enthalpy–entropy compensation relationship in the dissolution process was analyzed by calculating the thermodynamic parameters of the substances, and the results showed that the dissolution process of L 1 and L 2 was an enthalpy-driven heat absorption process. [ABSTRACT FROM AUTHOR]

Chiral sulfoxide is considered to be an ideal candidate ligand for transition-metal-catalyzed asymmetric reactions due to its ease of synthesis, stability, and exceptional S -stereological orientation control. This paper reviews the different types of asymmetrical reactions with chiral sulfoxide ligands in recent years, as well as a discussion of efficient methods for the preparation of some enantiomerically pure sulfoxides. 1 Introduction 2 Chiral Sulfoxides as Ligands in Metal-Catalyzed Asymmetric Catalysis 3 Synthesis of Chiral Sulfoxides 4 Conclusions [ABSTRACT FROM AUTHOR]

In this study, we synthesized two unsymmetrical and dipodal Schiff–Mannich combo ligands, namely benzoic acid (3-benzoimidazol-1-ylmethyl-2-hydroxy-5-methyl-benzylidene)-hydrazide (H2BBH) and the hydroxyl analogue 2-hydroxy-benzoic acid (3-benzoimidazol-1-ylmethyl-2-hydroxy-5-methyl-benzylidene)-hydrazide (H3BSH), for the selective detection of Zn2+ in semi-aqueous media. Both the probes selectively depict a turn-on response to Zn2+ as a result of the combined effect of chelation-induced enhanced fluorescence (CHEF) and photo-induced electron transfer (PET). Detailed experimental studies reveal that H2BBH and H3BSH can detect Zn2+ in solutions with limit of detections of 27 nM and 46 nM, respectively. The structures of probe-Zn2+ ensembles were proposed as [(HBBH)2Zn] and [(H2BSH)2Zn] by ESI-MS, FT-IR spectroscopy, 1H NMR titration and DFT/TD-DFT methods. Moreover, both the probes were successfully employed in the detection of Zn2+ in HuH-7 cells, seedlings of chickpea and mung beans, and paper strips. [ABSTRACT FROM AUTHOR]

Earth-abundant, cheap and non-toxic zinc-based coordination compounds are drawing research attention as promising candidates for various applications, such as photoluminescent materials and anticancer agents. In this paper we report six zinc complexes (1–3-NO3 and 1–3-Cl) with pyridyl-based thiazolyl–hydrazone ligands, which differ in the nature of substituents at the ligands' periphery, anion type, and geometry around the metal ion. The complexes were characterized by single-crystal and powder X-ray diffraction analysis, as well as IR and NMR spectroscopy. The symmetrical complexes 2-Cl and 3-Cl, where zinc atoms are located at a two-fold axis, do not exhibit photophysical properties, unlike their asymmetrical analogs 2-NO3 and 3-NO3 with the same complex cation. Asymmetrical pentacoordinated 1-Cl and hexacoordinated 1-NO3 complexes exhibit photophysical properties. An admixture of allowed intra-ligand (1IL) and chloro (X)-to-ligand charge-transfer (1XLCT) electronic transitions is responsible for the fluorescence of the 1-Cl complex. The origin of the emission of the 1-NO3 complex is ascribed to an admixture of 3IL and ligand-to-ligand charge-transfer (3LLCT) forbidden electronic transitions, while for 3-NO3 most electronic excitations are of LLCT character. The thermal stability of the complexes is in accord with the strength of respective intermolecular interactions. The antiproliferative activity of the complexes was in the nanomolar range on some of the investigated cancer cell lines. Contrary to the increase of antiproliferative activity of the complexes in comparison to the free ligands in cancer cell lines, an acute toxicity determined in the brine shrimp assay follows the opposite trend. The overall results suggest that Zn(II) thiazoyl–hydrazone complexes have considerable potential as multifunctional materials. [ABSTRACT FROM AUTHOR]

This paper investigates the effects of substituents in PNP-type ruthenium complexes in the catalytic hydrogenation of CO2 to formate using the DFT method. Six groups were considered as substituents linked to the P atom of the PNP ligand: hydrogen, methyl, iso-propyl, tert-butyl, cyclopentyl, and cyclohexyl. The substituent effects were analyzed from the perspectives of steric hindrance and promotion of hydrogen bonding. With the joint functions of steric hindrance and hydrogen bonding promotion during the CO2 coordination step, hydride addition step, and HCOO− rotation step, these groups exhibited very different substituent effects. The results showed that the methyl group was the most favorable substituent when the solvent's effects were not included, as it formed hydrogen bonding with relatively weak steric hindrance. The second favorable substituent was the iso-propyl group, while the tert-butyl group was the most unfavorable one, due to remarkable steric hindrance. When the substituent was cyclopentyl or cyclohexyl, the complex provided a wider open space for the reaction compared with the tert-butyl-substituted complex, because cyclopentyl and cyclohexyl are cyclic groups. Therefore, the principle for choosing the substituent in PNP-type complexes allowing the design of highly efficient catalysts for CO2 hydrogenation indicates that more hydrogen atoms but wider open space are ideal. In addition, the substituent's effects can be markedly impacted by the solvent used. [ABSTRACT FROM AUTHOR]

Illustration of Zn2+ induced formation of spheric aggregates at mid-pH for cellular entry. [Display omitted] Although the restriction of intramolecular motion has been well recognized as the fundamental of aggregation induced emission enhancement (AIEE), the regulation mechanism of gold nanoclusters (AuNCs) based AIEE system are still unclear. In this paper, we have investigated the Zn2+-induced AIEE process of thiolate ligands (i.e., cysteine, glutathione and an 8-mer peptide) protected AuNCs, which shows a pH-dependent evolution from single AuNCs to spheric aggregates to irregular network. Using photoluminescent enhancement ratio as an index, the concept of " mid-pH " is proposed to indicate the optimal pH for the formation of spheric AuNCs aggregates. Importantly, the surface ligands allow the formation of spheric AuNCs aggregates at tunable mid-pH between 5.7 and 7.5. Owing to the appropriate size and surface peptide targetability, the spheric AuNCs aggregates can be successfully screened for targeted tumor cell uptake and imaging at physiological pH. The cell uptake mechanism study showed that AuNCs aggregates was specifically recognized by arginine-glycine-aspartic acid (RGD) sequence on the ligand and integrin αvβ3 on the cell surface, thus mainly through clathrin-mediated endocytosis. This work provides new sight to artificially regulate the construction of efficient cellular imaging probes. [ABSTRACT FROM AUTHOR]

Nanomedicine is a speedily growing area of medical research that is focused on developing nanomaterials for the prevention, diagnosis, and treatment of diseases. Nanomaterials with unique physicochemical properties have recently attracted a lot of attention since they offer a lot of potential in biomedical research. Novel generations of engineered nanostructures, also known as designed and functionalized nanomaterials, have opened up new possibilities in the applications of biomedical approaches such as biological imaging, biomolecular sensing, medical devices, drug delivery, and therapy. Polymers, natural biomolecules, or synthetic ligands can interact physically or chemically with nanomaterials to functionalize them for targeted uses. This paper reviews current research in nanotechnology, with a focus on nanomaterial functionalization for medical applications. Firstly, a brief overview of the different types of nanomaterials and the strategies for their surface functionalization is offered. Secondly, different types of functionalized nanomaterials are reviewed. Then, their potential cytotoxicity and cost-effectiveness are discussed. Finally, their use in diverse fields is examined in detail, including cancer treatment, tissue engineering, drug/gene delivery, and medical implants. [ABSTRACT FROM AUTHOR]

Computational docking is used for optimizing known drugs and for defining new binders by simulating their binding mode and affinity. AutoDock tools have been widely cited as necessary tools in structure-based drug design. These methods are rapid enough to declare virtual screening of ligand libraries. We selected a target involved in transferases enzyme class and provided a fully reproducible docking protocol. This paper will show how docking techniques would be an important asset to identify new ligands interactions with transferases. We used Non-3D structures of chosen transferases and built models for the proteins in trying to find putative compounds against them. Five proteins have structural data available in uniprot with varying degrees of structural coverage. Using homology-based methods; structural coverage of these proteins and built models for them through Swiss model. Designed ligands are tested by Autodock vina to study the interacting sites with the proteins. We have predicted putative drug like molecules using molecular docking that could bind to transferases. The stability of a few of our top docked protein-inhibitor complexes was evaluated based on molecular docking simulations. Our proposed inhibitors should potentially bind to enzyme proteins and hinder their function. [ABSTRACT FROM AUTHOR]

Photorelease complexes represent a class of agents for which UV-visible light triggers the expulsion of a specfic molecule that is intrinsically part of the inner coordination sphere or held in close proximity to the metal centre. The reaction does not occur in the ground-state complex and requires a photon, but an additional agent may be present that facilitates the release process. In this context, the perspective article covers recent papers from the past five years (2017–2021) on metal-based complexes containing ligands that are expelled under light activation. In addition, the examples primarily focus on ligands with potential biological activity and have specfic therapeutic applications. Some examples include NO, CO, Cl−, peptides, pharmacophores and redox-active compounds. [ABSTRACT FROM AUTHOR]

Methylaluminoxane (MAO) is the most commonly used co-catalyst for transition metal-catalyzed olefin polymerization, but the structures of MAO species and their catalytic functions remain topics of intensive study. We are interested in MAO-assisted polymerization with catalysts L(R2)FeCl2 (L = tridentate pyridine-2,6-diyldimethanimine; imine-R = Me, Ph). It is our hypothesis that the MAO species is not merely enabling Fe–Me bond formation but functions as an integral part of the active catalyst, a MAO adduct of the Fe-precatalyst [L(R2)FeCl]+. In this paper, we explored the possible structures of acyclic and cyclic MAO species and their complexation with pre-catalysts [L(R2)FeCl]+ using quantum chemical approaches (MP2 and DFT). We report absolute and relative oxophilicities associated with the Fe ← O(MAO) adduct formation and provide compelling evidence that oxygen of an acyclic MAO species (i.e., O(AlMe2)2, 4) cannot compete with the O-donor in cyclic MAO species (i.e., (MeAlO)2, 7; MeAl(OAlMe2)2, cyclic 5). Significantly, our work demonstrates that intramolecular O → Al dative bonding results in cyclic isomers of MAO species (i.e., cyclic 5) with high oxophilicities. The stabilities of the [L(R2)FeClax(MAO)eq]+ species demonstrate that 5 provides for the ligating benefits of the cyclic MAO species 4 without the thermodynamically costly elimination of TMA. Mechanistic implications are discussed for the involvement of such Fe–O–Al bridged catalyst in olefin polymerization. [ABSTRACT FROM AUTHOR]

There is great interest to develop artificial intelligence-based protein–ligand binding affinity models due to their immense applications in drug discovery. In this paper, PointNet and PointTransformer, two pointwise multi-layer perceptrons have been applied for protein–ligand binding affinity prediction for the first time. Three-dimensional point clouds could be rapidly generated from PDBbind-2016 with 3772 and 11 327 individual point clouds derived from the refined or/and general sets, respectively. These point clouds (the refined or the extended set) were used to train PointNet or PointTransformer, resulting in protein–ligand binding affinity prediction models with Pearson correlation coefficients R  = 0.795 or 0.833 from the extended data set, respectively, based on the CASF-2016 benchmark test. The analysis of parameters suggests that the two deep learning models were capable to learn many interactions between proteins and their ligands, and some key atoms for the interactions could be visualized. The protein–ligand interaction features learned by PointTransformer could be further adapted for the XGBoost-based machine learning algorithm, resulting in prediction models with an average Rp of 0.827, which is on par with state-of-the-art machine learning models. These results suggest that the point clouds derived from PDBbind data sets are useful to evaluate the performance of 3D point clouds-centered deep learning algorithms, which could learn atomic features of protein–ligand interactions from natural evolution or medicinal chemistry and thus have wide applications in chemistry and biology. [ABSTRACT FROM AUTHOR]

The C content of the steel matrix has significant influence on the growth mechanism, microstructure and properties of the chromized layer. However, the relevant research literature is scarce. In this paper, seven kinds of low carbon alloy steels with C content ranging from 0.08 wt% to 0.45 wt% were selected as matrix for chromizing experiments under the same parameters. The effects of matrix C content on the growth mechanism, growth rate, structure and properties of the chromized layer were discussed. The results show that the chromized layer is composed of outer porous (Cr, Fe) 23 C 6 and (Cr, Fe) 7 C 3 carbides layer and inner dense Fe Cr phase layer for matrix with C content lower than or equal to 0.2 wt%. While when the matrix C content is >0.2 wt%, the chromized layer becomes three-layer structure: the surface (Cr, Fe) 23 C 6 phase layer, the middle (Cr, Fe) 7 C 3 phase layer and the bottom Fe Cr solid solution phase layer. The structure and thickness of Cr 23 C 6 phase layer formed in the early stage of chromizing play a decisive role in the inward diffusion of surface adsorbed Cr atoms and the growth rate of the permeated layer. With the C content of the matrix increases from low(0.08wt%C) to high(0.45wt.%C), the dense layer phases in chromized samples gradually changes from Fe Cr alloy phase with BCC structure to (Cr, Fe) 23 C 6 and (Cr, Fe) 7 C 3 carbides. And the wear resistance of the chromized layer increase. However, when the matrix C content is above 0.4 wt%, the structure and phases of the chromized layer are almost not affected by the matrix C content, so are the thickness and wear resistance. The results are helpful to the selection of steel matrix composition for chromizing and the optimization of chromizing process. • The C content of matrix has an important effect on the growth mechanism of the chromized layer. • The initial formed Cr 23 C 6 phase layer plays a decisive role in the growth rate of the chromized layer. • When the matrix C content is above 0.4 wt%, the properties of chromized layer are almost not affected by the matrix C content. [ABSTRACT FROM AUTHOR]

Cadmium magnesium telluride (CdMgTe) is a very perspective material for room temperature radiation detectors. In this paper, two large-size Cd 0.95 Mg 0.05 Te ingots doped with different In amounts were grown by vertical Bridgman method under Cd-compensated condition. It was found that the impurities were distributed inhomogeneously and In dopant mainly concentrated in the tail of two ingots. Compared with the ingot grown by doping with 5 ppm In, the ingot grown by doping with 10 ppm In had more uniform distribution of Mg element, higher IR transmittance, less Te inclusions and better crystal quality. FIB-TEM and HRTEM analysis showed that the size of Te precipitates was less than 10 nm, the composition of both crystals was rich in Cd and was single crystal with sphalerite structure. The type of dislocation was edge dislocation and the density was high. In addition, the maximum IR transmittance and highest resistivity were 64 % and 1.53 × 1010 Ω cm, respectively. The planar detector prepared with 10 ppm In doped crystal had an energy resolution of 19.6 % and a (μτ) e value of 1.38 × 10−3 cm2/V, which could meet the requirements for high performance room-temperature radiation detector. • CdMgTe is a very perspective material for room temperature radiation detectors. • Large-size Cd 0.95 Mg 0.05 Te ingots are successfully grown by the modified vertical Bridgman method. • Cd compensation and different In content conditions are used together to improve crystal resistivity. • The as-grown crystal with high resistivity can be used for detector. [ABSTRACT FROM AUTHOR]

• Structure design of PCHPMs with different organic ligands has been reviewed. • The effect of performance regulation has been discussed. • New understanding of the reversible mechanism of PCHPMs has been illustrated. • Applications and the future development trends are summarized. As discrete anionic metal–oxygen clusters, polyoxometalates (POMs) demonstrate immense advantages as photochromic materials owing to their good redox properties and photo-activity, as well as excellent stability. However, single inorganic POM materials exhibit a poor coloration rate. The increasing interest in this field focuses on realizing the design of diversified POM-based crystalline hybrid photochromic materials (PCHPMs) and exploring applications based on the electron-rich features of POMs. Alkylammonium, carboxylic acid, sulfonium cations, spiropyran, naphthalene diimide, and viologen ligands have been used to construct PCHPMs with a good photochromic property and reversibility. In particular, recent studies have reported that the introduction of electron-deficient viologen ligands affords a new category of hybrid materials as well as a new photochromic mechanism. In this review, by comparing different PCHPMs, recent advances on PCHPMs are summarized, especially in terms of the types of structures, new photochromic mechanisms, and applications, including photocatalysis, ink-free rewritable printing, and sensors. This paper can offer valuable guidance for researchers investigating POM-based hybrid photochromic materials. [ABSTRACT FROM AUTHOR]

The crystal structures and magnetic properties of three Mn(III) Schiff-base complexes [Mn(3-OMe-sal-N-1,5,8,12)]AsF 6 ·H 2 O (1) , [Mn(4-OMe-sal-N-1,5,8,12)]AsF 6 ·H 2 O (2) and [Mn(5-OMe-sal-N-1,5,8,12)]AsF 6 (3) have been studied. Complexes 1 and 2 show gradual SCO behavior. The transition temperatures of 2 is 98 K higher than that of 1. Due to the absence of crystallizing solvent water molecule, complex 3 maintains a HS state in the test temperature range. [Display omitted] Spin crossover (SCO), as a molecular bistable phenomenon, has attracted extensive interest. In this paper, the syntheses, crystal structures and magnetic properties of three Mn(III) hexadentate Schiff-base complexes [Mn(3-OMe-sal-N-1,5,8,12)]AsF 6 ·H 2 O (1) , [Mn(4-OMe-sal-N-1,5,8,12)]AsF 6 ·H 2 O (2) and [Mn(5-OMe-sal-N-1,5,8,12)]AsF 6 (3) have been reported. The substituent positions of ligands and solvent molecules have a cooperative effect on SCO behavior. Complex 1 shows a complete SCO between the high-spin (HS, S = 2) and low-spin (LS, S = 1) states without thermal hysteresis, and complex 2 shows a gradual incomplete SCO behavior. The transition temperatures of 2 (T 1/2 = 241 K) is 98 K higher than that of 1 (T 1/2 = 143 K), which indicates that the ligand field strength of (4-OMe-sal-N-1,5,8,12)2– is stronger than that of (3-OMe-sal-N-1,5,8,12)2–. Due to the absence of crystallizing solvent water molecule, complex 3 maintains a HS state in the test temperature range. [ABSTRACT FROM AUTHOR]

Heteroleptic copper(I) charge-transfer chromophores of the general formula Cu(diimine)(NacNacR) (NacNacR is a substituted β-diketiminate) are described. They are characterized by multinuclear NMR and X-ray crystallography. Increasing the conjugation on the diimine ligand stabilizes the LUMO, decrease the HOMOجLUMO gap, and shifts the charge-transfer absorption band to longer wavelengths. [Display omitted] • Heteroleptic copper(I) complexes supported by diimines and β-diketiminates. • Pseudo- C 2v molecular structures with intermolecular π-stacking. • Tunable redox potentials and HOMO–LUMO gaps. • Broad, intense charge-transfer bands throughout visible and near-infrared. • Near-panchromatic visible absorption. In this paper, a series of heteroleptic bis-chelate copper(I) complexes of the general formula Cu(N^N)(NacNacR), where N^N is the diimine ligand and NacNacR is the β-diketiminate ligand are introduced. The complexes are easily prepared by reacting NacNac ligands with CuO t Bu in the presence of diimine ligands. The molecular structures of all complexes are characterized by NMR spectroscopy and X-ray crystallography. The studies of cyclic voltammetry and UV–vis absorption spectra show that the HOMO and the LUMO energy level can be tailored by changing the substitution pattern of each ligand. The oxidation potential is dependent on the NacNac ligand, and the reduction potential shows the dependence on the diimine ligand. Tunable redox potentials and a wide range of visible absorption can make these copper(I) complexes promising candidates for applications in solar light harvesting. [ABSTRACT FROM AUTHOR]

[Display omitted] • The bicyclic α-iminophosphonates showed high synthetic possibilities. • Imidazoline I 2 receptors are promising therapeutic targets in neurodegeneration. • (Octahydropyrrolo[3,4- c ]pyrrol-1-yl)phosphonates show affinity/selectivity for imidazoline I 2 receptors. • This is the first time, we showed cognitive improvement in C. elegans after I 2 -IR ligands treatment. Recent studies pointed out the modulation of imidazoline I 2 receptors (I 2 -IR) by selective ligands as a putative strategy to face neurodegenerative diseases. Foregoing the classical 2-imidazoline/imidazole-containing I 2 -IR ligands, we report a family of bicyclic α-iminophosphonates endowed with high affinity and selectivity upon I 2 -IR and we advanced a representative compound B06 in preclinical phases. In this paper, we describe the synthetic possibilities of bicyclic α-iminophosphonates by exploring its ambivalent reactivity, leading to unprecedented molecules that showed promising activities as I 2 -IR ligands in human brain tissues and good BBB permeation capabilities. After in silico ADME prediction studies, we assessed the neuroprotective properties of selected compounds and beneficial effect in an in vitro model of Alzheimeŕs and Parkinson's disease. Along with their neuroprotective effect, compounds showed a potent anti-inflammatory response when evaluated in a neuroinflammation cellular model. Moreover, this is the first time that the neuroprotective effects of imidazoline I 2 -IR ligands in a transgenic Alzheimer's disease Caenorhabditis elegans strain are investigated. Using a thrashing assay, we found a significant cognition improvement in this in vivo model after treatment with the new bicyclic α-phosphoprolines. Therefore, our results confirmed the need of exploring structurally new I 2 -IR ligands and their potential for therapeutic strategies in neurodegeneration. [ABSTRACT FROM AUTHOR]

In this paper, we present four Co-MOFs using R-substituted isophthalic acid (R-H2BDC, R = H, OH and COOH) along with trigonal n-TBT (n = 3 or 4) as organic ligands. These Co-MOFs are formulated as {[Co(1,3-BDC)(4-TBT)2/3]·(H2O)(DMF)1.5}n (Co-MOF-1), {[Co(HO-BDC)(4-TBT)]·(EtOH)2(DMF)2}n (Co-MOF-2), {[Co(HO-BDC)(4-TBT)2/3]·(H2O)3(MeOH)3(DMA)}n (Co-MOF-3) and {[Co3(BTC)2(3-TBT)2(H2O)2]·(H2O)2(EtOH)5(DMA)1.5}n (Co-MOF-4), where H2BDC = isophthalic acid, OH–H2BDC = 5-hydroxyisophthalic acid and H3BTC = 1,3,5-tricarboxybenzene, 4-TBT = 1,3,5- tris(4-pyridyl)benzene and 3-TBT = 1,3,5-tris(3-pyridyl)benzene. Co-MOF-1, 2 and 3 are constructed from the dimeric Co2(COO)2 unit and exhibit 3D frameworks. In Co-MOF-4, the dimeric Co2(COO)2 unit and single nuclear CoII center are connected by BTC3− and 3-TBT ligands into a 3D network. The catalytic experiments revealed that four Co-MOFs can catalyze the oxidative coupling reaction of benzyl alcohols and aniline to imines with good to excellent conversions under solvent-free conditions and an air atmosphere. Co-MOF-4 exhibited the best catalytic performance and the catalyst could be reused for at least five cycles without losing its structural integrity and catalytic activity. [ABSTRACT FROM AUTHOR]

This paper describes the synthesis, and structural and spectroscopic characterizations of two doubly bridged dicopper(II) complexes, [Cu2(μ-H2L)(μ-OMe)](ClO4)4·2H2O (1) and [Cu2(μ-L)(μ-OH)](ClO4)2 (2), with a binucleating ligand (HL) derived from the Schiff base condensation of DFMP and N,N-dimethyldipropylenetriamine, and their biomimetic catalytic activities were related to CAO and phenoxazinone synthase using 3,5-di-tert-butylcatechol and o-aminophenol (OAPH), respectively, as model substrates. Structural studies reveal that the major differences in these structures appear to be from the distinct roles of the tertiary amine groups of the ligands, which are protonated in 1, whereas it coordinates the metal centers in 2. Magnetic studies disclose that two copper(II) centers are strongly antiferromagnetically coupled with slightly different J values, which is further interpreted and discussed. They exhibited very different biomimetic catalytic activities; whereas 2 is an efficient catalyst, complex 1 showed somewhat lower substrate oxidation. The higher reactivity in 2 is rationalized by the strong involvement of the tertiary amine group of the Schiff base ligand, where the substrate oxidation is favored because of the transfer of protons from the substrate to the tertiary amine group, showing the importance of the functional groups in proximity to the bimetallic active site. Emphasis was also given to probing the binding mode of the substrate using an electronically deficient tetrabromomocatechol (Br4CatH2) and the isolated compound [Cu6(μ-HL)2(μ-OH)2(Br4Cat)4](NO3)2·4H2O (3) which suggests that monodentate asymmetric binding of 3,5-di-tert-butylcatechol and OAPH occurs during the course of the catalytic reaction. [ABSTRACT FROM AUTHOR]

The synthesis, photophysics and reverse saturable absorption of two cationic dinuclear Ir(III) complexes bearing fluorenyl-tethered 2-(quinolin-2-yl)quinoxaline (quqo) ligands are reported in this paper. The two complexes possess intense and featureless diimine ligand localized 1ILCT (intraligand charge transfer)/1π,π* absorption bands at ca. 330 and 430 nm, and a weak 1,3MLCT (metal-to-ligand charge transfer)/1,3LLCT (ligand-to-ligand charge transfer) absorption band at >500 nm. Both complexes exhibit weak dual phosphorescence at ca. 590 nm and 710 nm, which are attributed to the 3ILCT/3π,π* and 3MLCT/3LLCT states, respectively. The low-energy 3MLCT/3LLCT state also gives rise to a moderately strong triplet excited-state absorption at 490–800 nm. Because of the stronger triplet excited-state absorption than the ground-state absorption of these complexes at 532 nm, both complexes manifest a moderate reverse saturable absorption (RSA) at 532 nm for ns laser pulses. Expansion of the π-conjugation of the fluorenyl-tethered diimine ligand in Ir-1 causes a slight red-shift of the 1ILCT/1π,π* absorption bands in its UV-vis absorption spectrum and the 3MLCT/3LLCT absorption band in the transient absorption spectrum and slightly enhances the RSA at 532 nm compared to that in Ir-2. This work represents the first report on dinuclear Ir(III) complexes that exhibit RSA at 532 nm. [ABSTRACT FROM AUTHOR]