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Reactions of tptz complexes of Cu(II), Co(II), and Fe(III) with [MV(CN)8]3− (M=Mo, W) anions produced three new heterobimetallic chain compounds (2–4). The mer-capped building block [CuII(tptz)(CF3SO3)2(CH3OH)]·2H2O (1) (tptz=2,4,6-tris(2-pyridyl)-1,3,5-triazine) was also isolated. The structures of 2, 3, and 4 consist of linked squares composed of alternating [MV(CN)8]3− and [M(tptz)]2+/3+ units bridged by cyanide ligands. Both {[CuII(tptz)MoV(CN)8]−·H3O+·CH3OH}∞ (2) and {[FeIII(tptz)WV(CN)8]·2CH3OH}∞ (4) exhibit an infinite ladder-type motif of edge-sharing squares, whereas {[CoII 2(tptz)2(H2O)2W2 V(CN)16CoII(H2O)4]·2H2O}∞ (3) is composed of molecular squares bridged by [Co(H2O)4]2+ cations. The magnetic behavior of 2 is dominated by ferromagnetic coupling between Cu(II) and Mo(V) spin centers. The isostructural compound 4 exhibits weak antiferromagnetic coupling between Fe(III) and W(V) spin centers. In the case of 3, magnetic studies indicate the presence of ferromagnetic interactions between Co(II) and W(V) centers and the ac data reveal a weak out-of-phase signal at low temperature which suggests single-chain magnet behavior. [ABSTRACT FROM AUTHOR]

A series of isostructural octanuclear lanthanide complexes of general formula [Ln8(sao)4(μ3-OH)4(NO3)12(DMF)12] (Ln = Nd (1), Sm (2), Eu (3), Gd (4), Tb (5), Dy (6), Ho (7), Er (8); DMF = dimethylformamide) have been prepared via reactions of salicylaldoxime (saoH2), tetramethylammonium hydroxide (Me4NOH) with the appropriate lanthanide nitrate salt (Ln(NO3)3·6H2O). The metallic skeletons of the complexes describe [Ln4] tetrahedra encapsulated inside a [Ln4] square with the inner core stabilised through μ3-OH− ions and the periphery by μ4-sao2− ligands. The magnetic properties of compounds 2–8 were investigated by dc and ac magnetometry. Temperature dependent ac magnetic susceptibility data reveal that the dysprosium analogue (6) displays an out-of-phase signal in the absence of an applied magnetic field indicative of slow relaxation of the magnetization typical of a Single-Molecule Magnet (SMM). Micro-SQUID measurements reveal temperature and sweep rate dependent hysteresis below 1.0 K. [ABSTRACT FROM AUTHOR]

Reactions of the main-group cation TlI with anions of 2,5-derivatives of TCNQ (TCNQ=7,7,8,8-tetracyanoquinodimethane) have led to the isolation of a family of unprecedented semiconducting main-group-metal-organic frameworks, namely, [Tl(TCNQX2)], (X=H, Cl, Br, I). A comparison of single-crystal and powder X-ray diffraction data revealed the existence of a third polymorph of the previously reported material Tl(TCNQ)] and two distinct polymorphs of [Tl(TCNQCl2)], whereas only one phase was identified for [Tl(TCNQBr2)] and [Tl(TCNQI2)]. These new results are described in the context of the structures of other known binary metal-TCNQ frameworks that display a variety of coordination environments for the central cation, namely, four-, six-, and eight-coordinate, and different arrangements of the adjacent TCNQ radicals-parallel versus perpendicular-in the stacked columns. The halogen substituents affect the structures and the properties of these compounds, owing to both steric and electronic effects as evidenced by the semiconducting properties of crystals of [Tl(TCNQCl2)] phase I, [Tl(TCNQBr2)], and [Tl(TCNQI2)], which correlate well with the distances of adjacent TCNQ radicals in the columns. 1D infinite Hückel model simulations of the band structures of [Tl(TCNQCl2)] phase I, [Tl(TCNQBr2)], and [Tl(TCNQI2)] were conducted with and without consideration of the TlI cations, the results of which indicate that the charge mobility does not strictly occur in one dimension. The modulations of the band structures with various assumptions of the energy difference (Δ) between the TlI 6s orbital and the TCNQ LUMO orbital were calculated and are discussed in light of the observed properties. [ABSTRACT FROM AUTHOR]

Abstract: In this work, we present a detailed AC magnetic susceptibility investigation of the metamagnet {[Mn(OH)(CH3CO2)2]·CH3CO2H·H2O}∞ (1). Compound 1 was previously reported and the magnetic properties were investigated. The data revealed that the compound is a linear-chain antiferromagnet with a phase transition at TN =6.1K to an ordered antiferromagnetic state and a metamagnetic transition at approximately 1000Oe from the antiferromagnetic phase to a paramagnetic phase. In this new study we report detailed AC susceptibility measurements which reveal frequency dependent data indicative of a slow relaxation process which was not previously described. These additional magnetic data support the conclusion that this compound is a rare example of an antiferromagnetic ordered system that displays magnetic relaxation properties induced by the intrinsic single chain magnet (SCM) properties of the canted homospin chains composing the material. [Copyright &y& Elsevier]

Abstract: Reactions of the organic donors tetrathiafulvalene (TTF), o-dimethyltetrathiafulvalene (o-Me2TTF), tetramethyltetrathiafulvalene (TMTTF), and tetrathiafulvalene tetrathiolate [TTF(SCH2CH2CN)4] with oxidizing agents of suitable potential resulted in the formation of stable salts in which the donors are present in their monocationic radical forms. The salts presented herein represent a series of reagents containing oxidized chalcofulvalene donors that can be used as starting materials for metathesis reactions with other cations. All of the salts were characterized by X-ray crystallography and UV–vis–NIR spectroscopy. [Copyright &y& Elsevier]

Abstract: Single crystals of two new coordination polymers {Fe(C5N3O)2(CH3CN)2}∞ (1) and {Co(C5N3O)2(C4H4O)2}∞ (2) have been prepared and their structures and magnetic properties determined. Reactions of TCNE with Fe4Cl8(THF)6 in acetonitrile/diethyl ether and TCNE with Co4Cl8(THF)6 in tetrahydrofuran both lead to the transformation of TCNE to 1,2,2-tricyanoethanolate and the formation of two new compounds consisting of infinite, two-dimensional sheets of [Fe(C4N3O)2(CH3CN)2] and [Co(C5N3O)2(C4H4O)2] units with bridging tricyanoethenolate groups. The 1,2,2-tricyanoethanolate ions coordinate to the FeII and CoII centers through two of its three CN groups and not via the O atom. The metal atoms are in slightly distorted octahedral environments with axially bonded acetonitrile and tetrahydrofuran molecules. These sheets are linked by hydrogen bonds involving the ethanolate O atoms and hydrogen atoms of the coordinated solvent molecules. [Copyright &y& Elsevier]

The syntheses and characterization of two new, highly soluble, single-molecule magnets [Mn12O12 (CF3COO)16-(H2O)4]·2CF3COOH·4H2O (1) and [Mn12O12 (CF3COO)16 (H2O)4]·CF3COOH·7H2O (2) are reported. Compound 1 was isolated from the reaction of [Mn12O12 (CH3COO)16(H2O)4] with trifluoroacetic acid in CH2CI2. Compound 1 crystallizes in the tetragonal space group /&4oline;, (No. 82) with unit cell parameters a = b = 18.128(3) Å, c = 13.048(3) Å, V = 4287.9(19) Å3, Z = 2 and is isostructural to [Mn12O12 (CH3COO)16(H2O)4]. Compound 2 was prepared from the reaction of [Mn12O12(CH3COO)16(H2O)4] with neat trifluoroacetic acid, and crystallizes in the monoclinic space group P21/n (No. 14) with unit cell parameters a = 15.221(8) Å, b = 21.870(12) Å, c = 27.217(15) Å, β = 90.53(1)°, V= 9060(9) Å3, and Z = 4. The dc magnetic susceptibility measurements in the 2–300 K temperature range support a high-spin ground state. The magnetization data collected in the 1–7 T field range from 1.8 to 4.0 K were best fit to the parameters S = 10, g = 2.15, D = -0.65 cm-1, and E = 0 cm-1 for 1 and S = 10, g = 1.87, D = -0.34 cm-1, and E = -0.10 cm-1 for 2. The ac susceptibility data for compound 1 reveal outof-phase (χm″) signals in the 4–7 K temperature range, whereas the χm′ signals for compound 2 appear below temperatures of 4 K. This variation in blocking temperatures is a consequence of the two different crystallographic forms of compounds 1 and 2. Compound 1 exhibits the same structural geometry and distortions found in [Mn12O12(CH3COO)16(H2O)4], while compound 2 is of lower molecular symmetry with two Jahn-Teller axes of distortion being oriented along oxide ligands. This different structural arrangement facilitates a different tunneling pathway that leads to a lower effective barrier for magnetization reorientation for compound 2. The substitution of the acetate ligands by trifluoroacetic acid was monitored by mass spectrometry, which is a convenient tool for judging completion of the substitution process. [ABSTRACT FROM AUTHOR]

Examines two new soluble iron-oxo complexes, di-μ-trifluoracetato-μ-oxo-bis[(2,2'-bipyridine-K[sup2]N,N')(trifluoroacetato-KO)iron(III)],[Fe[sub2]O(CF[sub3]CO[sub2])[sub4](C[sub10]H[sub8]N[sub2])[sub2]], and bis(2,2'-bipyridine)di-μ[sub3]-oxo-hexa-μ-trifluoroacetato-bis(trifluoroacetato)tetrairon(III) trifluoroacetic acid solvate. Chemical composition; Molecular structure; Magnetic properties.

Non-alcoholic fatty liver disease (NAFLD) is usually associated with obesity. However, it is crucial to recognize that NAFLD can also occur in lean individuals, which is frequently overlooked. Without an approved pharmacological therapy for lean NAFLD, we aimed to investigate whether the Ganjianglingzhu (GJLZ) decoction, a representative traditional Chinese medicine (TCM), protects against lean NAFLD and explore the potential mechanism underlying these protective effects. The mouse model of lean NAFLD was established with a methionine-choline-deficient (MCD) diet in male C57BL/6 mice to be compared with the control group fed the methionine-choline-sufficient (MCS) diet. After four weeks, physiological saline, a low dose of GJLZ decoction (GL), or a high dose of GJLZ decoction (GH) was administered daily by gavage to the MCD group; the MCS group was given physiological saline by gavage. Untargeted metabolomics techniques were used to explore further the potential mechanism of the effects of GJLZ on lean NAFLD. Different doses of GJLZ decoction were able to ameliorate steatosis, inflammation, fibrosis, and oxidative stress in the liver; GL performed a better effect on lean NAFLD. In addition, 78 candidate differential metabolites were screened and identified. Combined with metabolite pathway enrichment analysis, GL was capable of regulating the glucose and lipid metabolite pathway in lean NAFLD and regulating the glycerophospholipid metabolism by altering the levels of sn-3-O-(geranylgeranyl)glycerol 1-phosphate and lysoPC(P-18:0/0:0). GJLZ may protect against the development of lean NAFLD by regulating glucose and lipid metabolism, inhibiting the levels of sn-3-O-(geranylgeranyl)glycerol 1-phosphate and lysoPC(P-18:0/0:0) in glycerophospholipid metabolism. [ABSTRACT FROM AUTHOR]

Background: Different types of sedentary behavior are associated with several health outcomes, but the causality of these associations remains unclear.To conduct a systematic review and meta-analysis of Mendelian randomization (MR) studies investigating the associations between sedentary behaviors and health outcomes.A systematic search on PubMed, Embase, Web of Science, Scopus, and PsycINFO up to August 2023 was conducted to identify eligible MR studies. We selected studies that assessed associations of genetically determined sedentary behaviors and health outcomes. A meta-analysis was conducted to examine the causal associations when two or more MR studies were available. We graded the evidence level of each MR association based on the results of the main method and sensitivity analyses in MR studies.A total of 31 studies with 168 MR associations between six types of sedentary behavior and 47 health outcomes were included. Results from meta-analyses suggested a total of 47 significant causal associations between sedentary behaviors and health outcomes. Notably, more leisure TV watching is robustly correlated with increased risks of myocardial infarction, coronary artery disease, all-cause ischemic stroke, and type 2 diabetes. Conversely, robust inverse associations were observed between leisure computer use and risks of rheumatoid arthritis, Alzheimer’s disease, and gastroesophageal reflux disease.These findings suggest that different types of sedentary behavior have distinct causal effects on health outcomes. Therefore, interventions should focus not only on reducing sedentary time but also on promoting healthier types of sedentary behavior.CRD42023453828.Objectives: Different types of sedentary behavior are associated with several health outcomes, but the causality of these associations remains unclear.To conduct a systematic review and meta-analysis of Mendelian randomization (MR) studies investigating the associations between sedentary behaviors and health outcomes.A systematic search on PubMed, Embase, Web of Science, Scopus, and PsycINFO up to August 2023 was conducted to identify eligible MR studies. We selected studies that assessed associations of genetically determined sedentary behaviors and health outcomes. A meta-analysis was conducted to examine the causal associations when two or more MR studies were available. We graded the evidence level of each MR association based on the results of the main method and sensitivity analyses in MR studies.A total of 31 studies with 168 MR associations between six types of sedentary behavior and 47 health outcomes were included. Results from meta-analyses suggested a total of 47 significant causal associations between sedentary behaviors and health outcomes. Notably, more leisure TV watching is robustly correlated with increased risks of myocardial infarction, coronary artery disease, all-cause ischemic stroke, and type 2 diabetes. Conversely, robust inverse associations were observed between leisure computer use and risks of rheumatoid arthritis, Alzheimer’s disease, and gastroesophageal reflux disease.These findings suggest that different types of sedentary behavior have distinct causal effects on health outcomes. Therefore, interventions should focus not only on reducing sedentary time but also on promoting healthier types of sedentary behavior.CRD42023453828.Methods: Different types of sedentary behavior are associated with several health outcomes, but the causality of these associations remains unclear.To conduct a systematic review and meta-analysis of Mendelian randomization (MR) studies investigating the associations between sedentary behaviors and health outcomes.A systematic search on PubMed, Embase, Web of Science, Scopus, and PsycINFO up to August 2023 was conducted to identify eligible MR studies. We selected studies that assessed associations of genetically determined sedentary behaviors and health outcomes. A meta-analysis was conducted to examine the causal associations when two or more MR studies were available. We graded the evidence level of each MR association based on the results of the main method and sensitivity analyses in MR studies.A total of 31 studies with 168 MR associations between six types of sedentary behavior and 47 health outcomes were included. Results from meta-analyses suggested a total of 47 significant causal associations between sedentary behaviors and health outcomes. Notably, more leisure TV watching is robustly correlated with increased risks of myocardial infarction, coronary artery disease, all-cause ischemic stroke, and type 2 diabetes. Conversely, robust inverse associations were observed between leisure computer use and risks of rheumatoid arthritis, Alzheimer’s disease, and gastroesophageal reflux disease.These findings suggest that different types of sedentary behavior have distinct causal effects on health outcomes. Therefore, interventions should focus not only on reducing sedentary time but also on promoting healthier types of sedentary behavior.CRD42023453828.Results: Different types of sedentary behavior are associated with several health outcomes, but the causality of these associations remains unclear.To conduct a systematic review and meta-analysis of Mendelian randomization (MR) studies investigating the associations between sedentary behaviors and health outcomes.A systematic search on PubMed, Embase, Web of Science, Scopus, and PsycINFO up to August 2023 was conducted to identify eligible MR studies. We selected studies that assessed associations of genetically determined sedentary behaviors and health outcomes. A meta-analysis was conducted to examine the causal associations when two or more MR studies were available. We graded the evidence level of each MR association based on the results of the main method and sensitivity analyses in MR studies.A total of 31 studies with 168 MR associations between six types of sedentary behavior and 47 health outcomes were included. Results from meta-analyses suggested a total of 47 significant causal associations between sedentary behaviors and health outcomes. Notably, more leisure TV watching is robustly correlated with increased risks of myocardial infarction, coronary artery disease, all-cause ischemic stroke, and type 2 diabetes. Conversely, robust inverse associations were observed between leisure computer use and risks of rheumatoid arthritis, Alzheimer’s disease, and gastroesophageal reflux disease.These findings suggest that different types of sedentary behavior have distinct causal effects on health outcomes. Therefore, interventions should focus not only on reducing sedentary time but also on promoting healthier types of sedentary behavior.CRD42023453828.Conclusion: Different types of sedentary behavior are associated with several health outcomes, but the causality of these associations remains unclear.To conduct a systematic review and meta-analysis of Mendelian randomization (MR) studies investigating the associations between sedentary behaviors and health outcomes.A systematic search on PubMed, Embase, Web of Science, Scopus, and PsycINFO up to August 2023 was conducted to identify eligible MR studies. We selected studies that assessed associations of genetically determined sedentary behaviors and health outcomes. A meta-analysis was conducted to examine the causal associations when two or more MR studies were available. We graded the evidence level of each MR association based on the results of the main method and sensitivity analyses in MR studies.A total of 31 studies with 168 MR associations between six types of sedentary behavior and 47 health outcomes were included. Results from meta-analyses suggested a total of 47 significant causal associations between sedentary behaviors and health outcomes. Notably, more leisure TV watching is robustly correlated with increased risks of myocardial infarction, coronary artery disease, all-cause ischemic stroke, and type 2 diabetes. Conversely, robust inverse associations were observed between leisure computer use and risks of rheumatoid arthritis, Alzheimer’s disease, and gastroesophageal reflux disease.These findings suggest that different types of sedentary behavior have distinct causal effects on health outcomes. Therefore, interventions should focus not only on reducing sedentary time but also on promoting healthier types of sedentary behavior.CRD42023453828.PROSPERO Registration: Different types of sedentary behavior are associated with several health outcomes, but the causality of these associations remains unclear.To conduct a systematic review and meta-analysis of Mendelian randomization (MR) studies investigating the associations between sedentary behaviors and health outcomes.A systematic search on PubMed, Embase, Web of Science, Scopus, and PsycINFO up to August 2023 was conducted to identify eligible MR studies. We selected studies that assessed associations of genetically determined sedentary behaviors and health outcomes. A meta-analysis was conducted to examine the causal associations when two or more MR studies were available. We graded the evidence level of each MR association based on the results of the main method and sensitivity analyses in MR studies.A total of 31 studies with 168 MR associations between six types of sedentary behavior and 47 health outcomes were included. Results from meta-analyses suggested a total of 47 significant causal associations between sedentary behaviors and health outcomes. Notably, more leisure TV watching is robustly correlated with increased risks of myocardial infarction, coronary artery disease, all-cause ischemic stroke, and type 2 diabetes. Conversely, robust inverse associations were observed between leisure computer use and risks of rheumatoid arthritis, Alzheimer’s disease, and gastroesophageal reflux disease.These findings suggest that different types of sedentary behavior have distinct causal effects on health outcomes. Therefore, interventions should focus not only on reducing sedentary time but also on promoting healthier types of sedentary behavior.CRD42023453828. [ABSTRACT FROM AUTHOR]

The self-assembly of organic TCNQF•- radicals (2- fluoro-7,7,8,8-tetracyano-p-quinodimethane) and the anisotropic [Tb(valpn)Cu]3+ dinuclear cations produced a singlechain magnet (SCM) involving stacking interactions of TCNQF•- radicals (H2valpn is the Schiff base from the condensation of o-vanillin with 1,3-diaminopropane). Static and dynamic magnetic characterizations reveal that the effective energy barrier for the reversal of the magnetization in this hetero-tri-spin SCM is significantly larger than the barrier of the isolated single-molecule magnet based on the {TbCu} dinuclear core. [ABSTRACT FROM AUTHOR]

The self-assembly of organic TCNQF- radicals (2-fluoro-7,7,8,8-tetracyano-p-quinodimethane) and the anisotropic [Tb(valpn)Cu]3+ dinuclear cations produced a singlechain magnet (SCM) involving stacking interactions of TCNQF- radicals (H2valpn is the Schiff base from the condensation of o-vanillin with 1,3-diaminopropane). Static and dynamic magnetic characterizations reveal that the effective energy barrier for the reversal of the magnetization in this hetero-tri-spin SCM is significantly larger than the barrier of the isolated single-molecule magnet based on the {TbCu} dinuclear core. [ABSTRACT FROM AUTHOR]

Highlights: [•] Diruthenium tetraacetate is a fast homogeneous water oxidation catalyst (WOC). [•] Its limiting rate for oxygen evolution is 77s−1, second fastest reported in Ru chemistry. [•] It is the first metal–metal bonded WOC. [•] This catalyst exhibits high activity in a wide pH range. [•] The mechanism operates through a single-site and explains the fast kinetics. [ABSTRACT FROM AUTHOR]

Abstract: Four new salts of the radical cations of TMTSF (tetramethyltetraselenafulvalene), TMTTF (tetramethyltetrathiafulvalene), BEDT-TTF (bisethylenedithiotetrathia-fulvalene) (ET) and o-Me2TTF (o-4,4′-dimethyltetrathiafulvalene) with the metal–metal bonded dianion [Re2Cl8]2− were synthesized, and their structures and physical properties investigated. The structures of these semiconducting salts feature one-dimensional stacking of the donor molecules interleaved with [Re2Cl8]2− anions and interstitial solvent molecules. [Copyright &y& Elsevier]