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Carborane compounds, known for their exceptional thermal stability and non‐toxic attributes, have garnered widespread utility in medicine, supramolecular design, coordination/organometallic chemistry, and others. Although there is considerable interest among chemists, the integration of suitable carborane molecules into ferroelectric materials remains a formidable challenge. In this study, we employ the quasi‐spherical design strategy to introduce functional groups at the boron vertices of the o‐carborane cage, aiming to reduce molecular symmetry. This approach led to the successful synthesis of the pioneering ferroelectric crystals composed of cage‐like carboranes: 9‐OH‐o‐carborane (1) and 9‐SH‐o‐carborane (2), which undergo above‐room ferroelectric phase transitions (Tc) at approximately 367 K and 347 K. Interestingly, 1 and 2 represent uniaxial and multiaxial ferroelectrics respectively, with 2 exhibiting six polar axes and as many as twelve equivalent polarization directions. As the pioneering instance of carborane ferroelectric crystals, this study introduces a novel structural archetype for molecular ferroelectrics, thereby providing fresh insights into the exploration of molecular ferroelectric crystals with promising applications. [ABSTRACT FROM AUTHOR]

Reported herein is an electrochemical strategy for N-sulfonylation of azoles with sulfonyl hydrazides, offering efficient access to valuable N-sulfonated azoles. Organic radical species were involved in the process and EPR experiments provided evidence for the formation of intermediates in situ. The electrochemical reaction features metal-free, mild conditions, and a broad substrate scope (>70 examples). The gram-scale synthesis via an electrochemical continuous-flow reaction and late-stage modification of complex compounds is advocated for its practical value. [ABSTRACT FROM AUTHOR]

Accurate digital image segmentation is necessary for analyzing the characteristics of fuel spray from various optical measurements. However, some conventional segmentation methods cannot achieve the desired effect for the difficult task with severe noises such as schlieren images under diesel engine-like conditions. In this work, an image processing algorithm named Texture Assessment by Gradient Statistics (TAGS) was proposed for improving the recognition of spray images with noisy backgrounds, which utilizes gradient statistics reflecting texture to distinguish the spray region from the background region. The effects of the key parameters in the proposed algorithm on the segmentation quality were studied. And for validating the applicability and generalization of the proposed algorithm, a series of experiments on diesel evaporating sprays were conducted through high-speed photography of Mie-scattering and double-pass schlieren. It was found that the extraction of gradient statistics can enhance the difference between the spray and the background regions when their gray values are close, which contributes to the image segmentation. For the schlieren images with noisy backgrounds, the signal-to-noise ratio of the TAGS method increased from 1.24 to 9.40 compared with the conventional gray value subtraction thresholding method. The segmentation quality has low dependence on the algorithm parameters of TAGS, and a parameter setting method for its image processing program has been recommended, which enables the analysis of spray characteristics including the macroscopic morphology, the tip penetration and the projected area of liquid/vapor phases. [ABSTRACT FROM AUTHOR]

[Display omitted] • SIGIRR overexpression deprives the pro-inflammatory function of HBx. • SIGIRR overexpression suppresses HBx-induced NF-κB signaling activation through antagonizing MyD88 function. • Persistently high expression of SIGIRR may become a new strategy of organ inflammation suppressant drugs. Although antiviral drugs can effectively inhibit hepatitis B virus (HBV) replication, the maintenance of chronic inflammation in the liver is still considered to be an important cause for the progression of HBV-related liver disease to liver fibrosis and advanced liver disease. As an endogenous inhibitory receptor of IL-1R and TLR signaling pathways, single immunoglobulin interleukin-1-related receptor (SIGIRR) has been proven to reduce inflammation in tissues to maintain system homeostasis. However, the relationship between SIGIRR expression and HBV replication and inflammatory pathway activation in hepatocytes remains unclear. In this study, hepatitis B virus X protein (HBx) upregulated MyD88 in liver cells, promoting NF-κB signaling and inflammatory factor production with LPS treatment, and the cell supernatant accelerated the activation and collagen secretion of hepatic stellate cells. However, SIGIRR overexpression suppressed HBx-mediated MyD88/NF-κB inflammatory signaling activation and inflammatory cytokine production induced by LPS in hepatocytes and HBV replication hepatocytes. Although we did not find any effect of SIGIRR on HBV replication in vitro, this study investigated the role of SIGIRR in blocking the proinflammatory function of HBx, which may provide a new idea for the treatment of chronic hepatitis B. [ABSTRACT FROM AUTHOR]

Background: One forth whole-world population is infected with Mycobacterium tuberculosis (Mtb), but 90% of them are asymptotic latent infection without any symptoms but positive result in IFN-γ release assay. There is lack of ideal strategy to distinguish active tuberculosis (TB) and latent tuberculosis infection (LTBI). Some scientist had focused on a set of cytokines as biomarkers besides interferon- gamma (IFN-γ) to distinguish active TB and LTBI, but with considerable variance of results. This meta-analysis aimed to evaluate the overall discriminative ability of potential immune molecules to distinguish active TB and LTBI.Methods: PubMed, the Cochrane Library, and Web of Science databases were searched to identify studies assessing diagnostic roles of cytokines for distinguishing active TB and LTBI published up to August 2018. The quality of enrolled studies was assessed using Quality Assessment of Diagnostic Accuracy Studies-2 (QUADAS-2). The pooled diagnostic sensitivity and specificity of each cytokine was calculated by using Meta-DiSc software. Area under the summary receiver operating characteristic curve (AUC) was used to summarize the overall diagnostic performance of each biomarker.Results: Fourteen studies with 982 subjects met the inclusion criteria, including 526 active TB and 456 LTBI patients. Pooled sensitivity, specificity and AUC for discriminating between active TB and LTBI were analyzed for IL-2 (0.87, 0.61 and 0.9093), IP-10 (0.77, 0.73 and 0.8609), IL-5 (0.64, 0.75 and 0.8533), IL-13 (0.75, 0.71 and 0.8491), IFN-γ (0.67, 0.75 and 0.8031), IL-10 (0.68, 0.74 and 0.7957) and TNF-α (0.67, 0.64 and 0.7783). The heterogeneous subgroup analysis showed that cytokine detection assays, TB incidence, and stimulator with Mtb antigens are main influence factors for their diagnostic performance.Conclusions: The meta-analysis showed cytokine production could assist the distinction between active TB and LTBI, IL-2 with the highest overall accuracy. No single biomarker is likely to show sufficiently diagnostic performance due to limited sensitivity and specificity. Further prospective studies are needed to identify the optimal combination of biomarkers to enhanced diagnostic capacity in clinical practice. [ABSTRACT FROM AUTHOR]

Background: In recent years, studies on the diagnostic accuracy of in-house real-time PCR (hRT-PCR) assay for the detection of Mycobacterium tuberculosis (Mtb) have been reported with unignorable discrepancies. To assess the overall accuracy of the hRT-PCR assay for Mtb diagnosis in different samples for individuals with active pulmonary and extra-pulmonary Mtb infection, a systematic review and meta-analysis were performed.Methods: The PUBMED, EMBASE, Web of Science, and Cochrane databases were searched up to June 2017 for eligible studies that estimated diagnostic sensitivity and specificity with the hRT-PCR assay in respiratory and non-respiratory samples in pulmonary and extra-pulmonary Mtb infection patients, with Mtb culture as the reference standard. Bivariate random effect models were used to provide pooled estimation of diagnostic accuracy. Further, subgroup and meta-regression analyses were performed to explore sources of heterogeneity. The risk of bias was assessed by the QUADAS-2 tool.Results: Of the 3589 candidate studies, 18 eligible studies met our inclusion criteria. Compared to Mtb culture data, the pooled sensitivity and specificity were 0.96 and 0.92, respectively. The diagnostic odds ratio (DOR) was 192.96 (95% CI 68.46, 543.90), and the area under the summary ROC curve (AUC) was 0.9791. There was significant heterogeneity in sensitivity and specificity among the enrolled studies (p < 0.001). The studies with high-quality assessment and application of respiratory specimen were associated with better accuracy.Conclusions: In low-income/high-burden settings, our results suggested that the hRT-PCR assay could be a useful test for the diagnosis of TB with high sensitivity and specificity. [ABSTRACT FROM AUTHOR]

Reported herein is a photochemical strategy for C(sp3)–H azolation of ethers via a hydrogen-atom transfer and radical-polar crossover process, offering efficient access to valuable N-alkylated azoles under visible-light irradiation. The protocol is metal-free and photocatalyst-free, and exhibits good to excellent yields and broad substrate scope with regard to azoles. EPR experiments provide evidence for the formation of intermediates formed in situ. [ABSTRACT FROM AUTHOR]

Organic ferroelectrics have received a great deal of interest due to their exclusive properties. However, organic ferroelectrics have not been fully explored, which hinders their practical application. Here, we presented a novel metal‐free organic molecular ferroelectric [4‐MCHA][ClO4] (1) (4‐MCHA=trans‐4‐methylcyclohexylamine), which exhibits an above‐room‐temperature of 328 K. Strikingly, the single crystal structure analysis of 1 shows that the driving force of phase transition is related to the interesting chair‐boat conformation change of 4‐MCHA cation, in addition to the order‐disorder transition of ClO4− anion. Using piezoelectric response force microscopy (PFM), the presence of domains and the implemented polarization switching were clearly observed, which explicitly determined the presence of room‐temperature ferroelectricity of 1. As far as we know, the ferroelectric phase transition mechanism attributed to the conformational change in a trans isomeric cation is very rare. This research enriched the path of designing ferroelectric materials and smart materials. [ABSTRACT FROM AUTHOR]

Solute Carrier Family 25 (SLC25) is the largest family of mitochondrial membrane proteins in the human body, consisting of 53 members. Mitochondrial phosphate carriers (MPiC), cellular iron metabolism, voltage-dependent anion channels (VDAC), and oxidative phosphorylation in the SLC25 family play dominant roles in material transport, energy metabolism, etc. SLC25 family-related proteins are involved in the regulation of the progression of a variety of cancers, including colon, gastric, and lung cancers. In addition, the SLC25 family has been implicated in endoplasmic reticulum stress (ERS) and immunity. Since SLC25 family proteins are involved in cancer progression and are associated with endoplasmic reticulum stress and immunity, exploring inhibitors of SLC25 family-related proteins is essential. However, the exact mechanism of SLC25 family-related proteins involved in cancer, as well as potential targets and SLC25 inhibitors have not been reported in the literature. This article focuses on summarizing the relevance of the SLC25 family to cancer, ERS, and immunity. This review also provides a comprehensive overview of SLC25 family-related inhibitors. [ABSTRACT FROM AUTHOR]

A novel solid-state second harmonic generation (SHG) organic–inorganic hybrid switch [Me3NCH2CH2F]FeBr4 (1) exhibits genuine three-step "on–off–on–off" SHG-switching above-room temperature, which has potential applications in multi-step optical devices. [ABSTRACT FROM AUTHOR]

Two inorganic–organic hybrid compounds [(C 7 H 18 N 2 ) 6 Pb 7 I 26 ] ( 1 ) and [(C 7 H 18 N 2 )Pb 2 I 6 ] ( 2 ) have been synthesized by reactions of 2-(2-aminoethyl)-1-methylpyrrolidine and lead iodide with 1: 1 and 1: 2 M ratios in concentrated HI aqueous. The single-crystal X-ray diffraction revealed that the inorganic component in compound 1 can be viewed as a wave-like 2D sheet built up from alternatively perovskite and non-perovskite structure types connected with corner-, edge- sharing octahedral [PbI 6 ]; and that in complex 2 is a zigzag chain constructed with edge- sharing octahedral [PbI 6 ]. In addition, both complexes showed fluorescent properties with complex 1 emitted green light at 545 nm and complex 2 emitted blue light at 467 nm. [ABSTRACT FROM AUTHOR]

The reaction of manganese(II) halide MnCl 2 ·4H 2 O and tris(2-aminoethyl)amine N(CH 2 CH 2 NH 2 ) 3 in the concentrated acid HCl at 65 °C resulted in the formation of an inorganic–organic hybrid complex: [(C 6 H 22 N 4 ) 2 (H 3 O)(MnCl 6 )(MnCl 5 )(Cl) 2 ]·3H 2 O ( 1 ) and a known byproduct [(C 6 H 22 N 4 )Cl 4 ]·H 2 O. The analogue reactions between MnBr 2 ·4H 2 O and N(CH 2 CH 2 NH 2 ) 3 in HBr acid gave a pure complex [(C 6 H 22 N 4 ) 2 Br 5 ](MnBr 5 ) ( 2 ). Crystal structures revealed that Mn centers in 1 adopted trigonal bipyramidal and octahedral two geometries, while in 2 showed only trigonal bipyramidal geometry. Luminescent investigation exhibited complex 1 gave pink luminescence and complex 2 emitted yellow light in solid states, which were both directly originated from the coordinated geometries of Mn 2+ ion. [ABSTRACT FROM AUTHOR]

The reaction of manganese (II) halides MnX and benzothiazole (btz) in the concentrated acids HX (X = Cl, Br) at 80 °C resulted in the formation of two inorganic-organic hybrid complexes: [(btz)(MnX)]·2HO (X = Cl, 1; X = Br, 2). Both compounds showed green luminescence and exhibited moderate quantum yields of 43.17 % for 1 and 26.18 % for 2, which were directly originated from the tetrahedral coordination of Mn ion. Two organic − inorganic hybrids [(btz)(MnX)]·2HO based on MnCl, benzothiazole and halide acids emitted green light with the moderate quantum efficiencies when excited by 365 nm light. [ABSTRACT FROM AUTHOR]

Three-dimensional (3D) hybrid organic–inorganic perovskites (HOIPs) have attracted tremendous research interest due to their unique structure and promising applications. However, research on the design, synthesis and properties of this kind of metal-free crystalline material is still in the exploratory stage. Herein, two 3D perovskite molecules [1,4-3.2.2-dabcn]NH4Br3 (1) and [1,4-3.2.2-dabcn]NH4I3·0.5H2O (2) were obtained by reacting 1,4-diazabicyclo[3.2.2]nonane (1,4-3.2.2-dabcn) with NH4X (X = Br and I) in the corresponding concentrated halogen acids. The single X-ray diffraction results demonstrated that the inorganic framework structures in compounds 1 and 2 constructed with NH4Br and NH4I are completely different, caused by the radius of the bromide ion being smaller than that of the iodide ion. The 3D framework of compound 1 is constructed with a coplanar dimer [(NH4)2Br6]2− as the basic building unit, leading to the expanded 3D perovskite framework structure with a larger cavity to accommodate the 1,4-3.2.2-dabcn molecule. Nevertheless, compound 2 adopts a familiar 3D crystal framework structure with corner-sharing [(NH4)I6] octahedra, where the [1,4-3.2.2-dabcn] cations and water solvent molecule are confined in the cavities enclosed by the octahedra. Notably, both compounds exhibit reversible phase transition, dielectric anomaly and the second harmonic generation (SHG) effect. From the perspective of molecular design, this work is of great significance to guide the construction of new 3D metal-free perovskite molecular materials with reversible properties. [ABSTRACT FROM AUTHOR]

Although organic molecule phase transition materials (OMPTM) have been studied by many scholars owing to their light weight and easy processing, single-component OMPTM with two reversible phase transitions have rarely been reported. Herein, we report an organic inner salt, 1-sulfo-4-dimethylamino-pyridinium (1), which exhibits two phase transitions at 286 K and 311 K, accompanied by obvious dielectric anomalies. Moreover, the variable-temperature single X-ray crystal structure analysis revealed that 1 undergoes an order–disorder symmetry breaking from 243 K (phase I) to 293 K (phase II), in which the centrosymmetric space group P21/n is transformed into the space group of Pnma. However, from phase II to phase III, there is no space group change, and 1 proceeds with an isostructural phase transition. Overall, this study highlights the exploration of the phase transition mechanism of single-component OMPTM. [ABSTRACT FROM AUTHOR]

The emergence of (CH3NH3)PbI3 has brought the development of three‐dimensional (3D) organic‐inorganic hybrid perovskite (OIHP) structures with ABX3 type to a higher level; however, most 3D frameworks are constructed by corner‐sharing of BX6 octahedra. Herein, we substituted the spherical molecule 1,4‐diazabicyclo[2.2.2]octane (2.2.2‐dabco) with 1,4‐diazabicyclo[3.2.2]nonane (1,4‐3.2.2‐dabcn) as a template to react with RbX (X=Br, I) in the corresponding HX acids under the consideration of reducing the molecular symmetry. Two 3D OIHP compounds [1,4‐3.2.2‐H2dabcn]RbI3⋅H2O (1) and [1,4‐3.2.2‐H2dabcn]RbBr3 (2) crystallized in non‐centrosymmetric point group mm2 before the phase transition point were isolated. Among them, the 3D inorganic framework of 1 is constructed by sharing the corner of [RbI6] octahedra, while that of 2 is constructed by sharing the corner and face of [RbBr6] octahedra to acquire large cavities to accommodate the organic amine cation [1,4‐3.2.2‐H2dabcn]2+; this 3D framework type is unprecedented in the OIHPs. As expected, compounds 1 and 2 exhibit reversible phase transition, dielectric and second harmonic generation (SHG) and ferroelectric properties, in which the phase transition temperature of 2 at 374 K is much higher than compound 1 at 280 K. [ABSTRACT FROM AUTHOR]

Recently, hybrid organic‐inorganic lead halide materials have attracted great attention for their applications in the fields of light‐emitting diodes, photovoltaics, photodetector. However, these hybrid materials usually suffer from environmental and human health issues because of the toxic lead moieties. Herein, we report a novel lead‐free bismuth iodide phase transition material, [NH3(CH2)7NH3][BiI5] (1), which undergoes a reversible phase transition at high temperature 351.7 K and exhibits a step fashion dielectric anomaly. The structural phase transition of 1 is mainly originated from the order‐disorder transition of the 1,7‐heptanediamine cations. Besides, the solid‐state UV‐vis spectrum of 1 displays an intense adsorption at around 658 nm; which gives an indirect bandgap of 1.89 eV. Such a small bandgap value is comparable to most of the organic‐inorganic hybrid lead halide type semiconductors. We believe this study will shed light on the exploration of lead‐free organic‐inorganic hybrid metal halide semiconductors toward future device applications. [ABSTRACT FROM AUTHOR]

• Synthesis two lead-free halides [3-FPEA] 3 (SbCl 4)Cl 2 and [3-FPEA] 4 (BiI 6)I. • Both hybrid perovskites have reversible phase transitions. • Both materials are lead-free semiconductor materials. Metal halide organic-inorganic hybrid perovskite is a kind of rapid development of semiconductors but its major development has been concentrated in lead-based perovskites. Here we report two zero-dimensional non-lead halide perovskites [3-FPEA] 3 (SbCl 4)Cl 2 (1) and [3-FPEA] 4 (BiI 6)I (2) (3-FPEA = 3-fluorophenethylamine) with the reversible phase transitions. The differential scanning calorimetry (DSC) and UV-vis absorption measurements of 1 and 2 revealed that the phase transition temperatures are 350 K (1) and 335 K (2), the bandgaps are 3.53 eV (1) and 2.14 eV (2), respectively. The room temperature X-ray single crystal diffraction showed the cation [3-FPEA]+ in 1 and 2 proceeds a twofold disorder, and the anions in 1 are a dimer [Sb 2 Cl 10 ] constructed with [SbCl 6 ] octahedra by sharing the Cl···Cl edge, and the anions in 2 are the discrete [BiI 6 ] octahedron. This study can provide an effective molecular design strategy for exploring and investigating non-lead-based halide perovskite semiconductive phase change materials. [Display omitted] [ABSTRACT FROM AUTHOR]

Tuberculosis (TB), a serious disease caused by Mycobacterium tuberculosis (Mtb), remains the world's top infectious killer. It is well-established that TB can circumvent the host's immune response for long-term survival. Macrophages serve as the major host cells for TB growth and persistence and their altered functions are critical for the response of the host defense against TB exposure (elimination, latency, reactivation, and bacillary dissemination). Noncoding RNAs are crucial posttranscriptional regulators of macrophage discrimination. Therefore, this review highlights the regulatory mechanism underlying the relationship between noncoding RNAs and macrophages in TB infection, which may facilitate the identification of potential therapeutic targets and effective diagnosis biomarkers for TB disease. • Macrophages persistence and their altered functions are critical for the response of the host defense against TB exposure. • Noncoding RNAs are crucial posttranscriptional regulators of macrophage discrimination in tuberculosis infection. • The regulatory mechanism between noncoding RNAs and macrophages in TB infection is complexed. [ABSTRACT FROM AUTHOR]

Abstract Reactions of 3-fluoro-N-methylbenzylamine (FBMA) with PbBr 2 in concentrated HBr aqueous solution afforded a two-dimensional (2D) single layered organic-inorganic hybrid material [(FBMA) 2 PbBr 4 ], which was confirmed by X-ray single crystal diffraction, infrared (IR) spectroscopy and powder X-ray diffraction (PXRD). The thermodynamic DSC analysis revealed it has a pair of reversible phase transition peaks with large thermal hysteresis exhibiting a first-order type phase transition. The variable-temperature single crystal diffraction proved the phase transition is originated from the order and disorder of organic-inorganic hybrid structures at room and high temperatures. Simultaneously compound [(FBMA) 2 PbBr 4 ] exhibited a strong emission peak at 443 nm when under an excitation wavelength of 380 nm. Graphic abstract A new two-dimensional (2D) single layered organic-inorganic hybrid material (FC 6 H 4 CH 2 NH 2 CH 3) 2 [PbBr 4 ] showed a first-order type phase transition, which was originated from the order-disorder transition of organic-inorganic hybrid structures at room and high temperatures. fx1 Highlights • A new layered organic-inorganic-hybrid perovskite is designed, synthesized, and characterized. • The relationship between phase transitions and structural changes is addressed. • The optical property of (FC 6 H 4 CH 2 NH 2 CH 3) 2 [PbBr 4 ] is studied. [ABSTRACT FROM AUTHOR]

Five tetradentate ligands, L 1 – 5 , bearing the moiety of bis(pyridin-2-ylmethyl)amine ( 1 ) and their complexes with Mn(II) were prepared. All the compounds and metal complexes were appropriately characterized. The five manganese(II) complexes ( 3a–e ) are of the formula, [Mn(II) L x Cl 2 ] (x = 1-5), as suggested by the crystal structure of complexes 3b and 3c . All the ligands except for L 3 possess two iodobenzene groups via an ether linkage (except for L 1 ) with various lengths. By using oxone as an oxidant, the catalytic activity of these complexes on the oxidation of ethylbenzene to acetophenone in acetonitrile/water at room temperature was studied. Our results showed that the pendant iodophenyl groups play a synergetic role with the metal center in the catalysis, and complex 3b possesses the most appropriate length of the linkage between the iodobenzene group and the metal center. EPR and FTIR data suggest that the metal center of the active species should be Mn(IV) after the oxidation of oxone under the reaction conditions. A catalytic mechanism was also proposed based on the experimental observations. [ABSTRACT FROM AUTHOR]

Abstract : Three cyclic thioesters of the formula ' $$-\hbox {SCH}_{2}\hbox {CH}_{2}\hbox {SCO}(\hbox {CH}_{2})_{\mathrm{n}}-$$ ' ( $$\mathbf{L}_{\mathbf{1}}, \hbox {n} = 0; \mathbf{L}_{\mathbf{2}}, = 1, \mathbf{L}_{\mathbf{3}}, \hbox {n} = 2$$ ) and their reactions with $$\hbox {Fe}_{3}(\hbox {CO})_{12}$$ are reported. All the reactions produced a known diiron complex, [ $$\hbox {Fe}_{2}(\upmu \hbox {-}\hbox {S}_{2}\hbox {C}_{2}\hbox {H}_{4})(\hbox {CO})_{6}$$ ] ( 1), which suggested that in the reactions, cleavage of C-S bond to generate ' $$\hbox {SCH}_{2}\hbox {CH}_{2}\hbox {S}$$ ' fragment is a common pathway for all the three ligands. In the case of ligand $$\mathbf{L}_{\mathbf{2}}$$ , a new complex 2, [ $$\hbox {Fe}_{2}\{\upmu \hbox {-}\hbox {SC}_{2}\hbox {H}_{4}(\hbox {SCH}_{2})\hbox {-}\upkappa \}(\hbox {CO})_{6}$$ ] was isolated and structurally characterized. In the reaction of ligand $$\mathbf{L}_{\mathbf{3}}$$ , an unknown iron carbonyl product was isolated in addition to complex 1. Although its precise structure was not established due to its instability and low yield, its infrared spectrum and decomposing into complex 1 implied that the product may be a cluster with higher nuclearity. The experimental observations suggested that with the increase of the ring size of the cyclic thioester ligands, further bond cleavages were involved in the reaction in addition to that leading to complex 1. GRAPHICAL ABSTRACT: SYNOPSIS Reaction of cyclic thioester ligands with triiron dodecacarbonyl leads to scission of C-S (C) bond which is initiated by the coordination of the S atom to the Fe atom. The larger the ring size of the ligand, the more diverse are the bond cleavages. [ABSTRACT FROM AUTHOR]

Abstract: Reacting a bidentate ligand H 2 L, 2-(2-methoxybenzyl)-2-methylpropane-1,3-dithiol, with Fe3(CO)12 formed a diiron hexacarbonyl complex (1Me) from which a diiron hexacarbonyl complex (1H) pendant with a phenolic group was derived via in-situ demethylation. Further deprotonation of complex 1H gave a diiron pentacarbonyl species (1) in which a rare bond between the soft metal FeI and the relatively hard base phenolate formed, FeI-OR (R = phenolic moiety). This bonding may be a suitable mimic of the bonding feature, {FeIFeI}R-OH/OH2 found in the [FeFe]-hydrogenase. [Copyright &y& Elsevier]

Two-dimensional (2D) organic-inorganic hybrid perovskite (OIHP) has the advantages of excellent material stability, structural diversity and ease of manufacturability. It is worth noting that the fluorination strategy has been recognized as a convenient molecular design method that can effectively customize and optimize physical and chemical properties in 2D OIHP materials. However, selection the fluorine-chlorine double substituted organic amine to construct lead halide OIHP molecules was not reported. Here, for the first time, we successfully obtained a 2D metal halide perovskite compound [4-Cl-2-FBA] 2 PbBr 4 (1) by reactions of lead bromide with two equivalents of 4-chloro-2-fluorobenzylamine [4-Cl-2-FBA] in concentrated HBr aqueous solution. Its crystal structure and purity were confirmed by X-ray single crystal diffraction and powder X-ray diffraction (PXRD). Differential scanning calorimetry (DSC) and dielectric measurement analyses showed the phase transition (PT) temperature of 1 is 380.1 ​K which is higher than that of [2-FBA] 2 PbBr 4 , (2-FBA ​= ​2-fluorobenzylammonium, 364 ​K), but lower than those of (benzylammonium) 2 PbBr 4 (405 ​K) and [PFBA] 2 PbBr 4 (PFBA ​= ​perfluorobenzylammonium, 440 ​K). A two-dimensional (2D) organic-inorganic hybrid perovskite material [4-Cl-2-FBA] 2 PbBr 4 (1) with high phase transition temperature and semiconductive property was isolated by reactions of lead bromide with two equivalents of 4-chloro-2-fluorobenzylamine [4-Cl-2-FBA] in concentrated HBr aqueous solution. [Display omitted] • A fluorine and chlorine substituted 2D metal halide perovskite was firstly prepared by reactions of PbBr 2 ​with 4-chloro-2-fluorobenzylamine. • DSC analysis showed the phase transition temperature of ​ 1 ​is 380.1 K which is higher than that of [2-FBA] 2 PbBr 4 ​at 364 K. • The 2D metal halide perovskite was characterized by the variable temperature X-ray single crystal diffraction. [ABSTRACT FROM AUTHOR]

A trilayer [(C 4 H 3 SCH 2 NH 3) 2 (CH 3 NH 3) 2 Pb 3 I 10 ] material was synthesized by carefully controlling the reaction ratio of 2-thienylmethylamine, methylamine and lead(II) iodide in concentrated HI/H 3 PO 2 aqueous. The DFT calculation indicates that it is a direct band gap semiconductor (E g = 1.60 eV). • A trilayered organic-inorganic-hybrid perovskite is designed, synthesized, and characterized. • The optical properties of the trilayered perovskite compound are studied by Uv absorption and DFT calculation. • The relationship between the optical and structure is addressed. A lead(II) organic-inorganic hybrid perovskite material [(TMA) 2 (MA) 2 Pb 3 I 10 ] (1) has been synthesized by reactions of 2-thienylmethylamine (TMA) and methylamine (MA) with PbI 2 in HI/H 3 PO 2 aqueous solution. The crystallographic diffraction indicated the inorganic moiety in 1 is a trilayered perovskite structure constructed with [PbI 6 ] octahedra, and the two organic amines are located between the inorganic layers, or embedded in the octahedral cavity of inorganic layers. The solid UV–vis absorption peak of compound 1 is located at 600 nm, and the bandgap calculated by DFT is 1.60 eV, both indicating it is a semiconductor and has potential application in organic-inorganic hybrid solar cell. [ABSTRACT FROM AUTHOR]

Halogen engineering offers a means of enhancing the physical properties of materials by fine-tuning the rotational energy barrier and dipole moment, which proved to be effective in achieving switchable phase transitions and optical responses in materials. In this work, by substituting the methyl group in ligand N -ethyl-1,5-diazabicyclo[3.3.0]octane (CH 3 CH 2 -3.3.0-Dabco) with halogen atoms X (Cl or Br) and then contining to react it with FeBr 3 in a HBr aqueous solution, we successfully synthesized three kinds of organic-inorganic hybrid switchable phase-change materials, [CH 3 CH 2 -3.3.0-Dabco]FeBr 4 ( 1 ), [ClCH 2 -3.3.0-Dabco]FeBr 4 ( 2 ), and [BrCH 2 -3.3.0-Dabco]FeBr 4 ( 3 ), which were fully characterized by single-crystal X-ray diffraction and variable-temperature powder X-ray diffraction. Compared to compound 1 , compounds 2 and 3 show two pairs of reversible phase transitions, dielectric anomalies, and a second-harmonic-generation effect, which are successfully induced due to the halogen substitution. This study offers an effective molecular design strategy for the exploration and construction of iron halide organic-inorganic hybrid materials with temperature-adjustable physical properties.

Reported herein is a photochemical strategy for C(sp 3 )-H azolation of ethers via a hydrogen-atom transfer and radical-polar crossover process, offering efficient access to valuable N -alkylated azoles under visible-light irradiation. The protocol is metal-free and photocatalyst-free, and exhibits good to excellent yields and broad substrate scope with regard to azoles. EPR experiments provide evidence for the formation of intermediates formed in situ .

Organic ferroelectrics have received a great deal of interest due to their exclusive properties. However, organic ferroelectrics have not been fully explored, which hinders their practical application. Here, we presented a novel metal-free organic molecular ferroelectric [4-MCHA][ClO 4 ] (1) (4-MCHA=trans-4-methylcyclohexylamine), which exhibits an above-room-temperature of 328 K. Strikingly, the single crystal structure analysis of 1 shows that the driving force of phase transition is related to the interesting chair-boat conformation change of 4-MCHA cation, in addition to the order-disorder transition of ClO 4 - anion. Using piezoelectric response force microscopy (PFM), the presence of domains and the implemented polarization switching were clearly observed, which explicitly determined the presence of room-temperature ferroelectricity of 1. As far as we know, the ferroelectric phase transition mechanism attributed to the conformational change in a trans isomeric cation is very rare. This research enriched the path of designing ferroelectric materials and smart materials., (© 2023 Wiley-VCH GmbH.)

Reactions of a chiral and quasi-spherical molecule [1 S ,4 S -2,5-2.2.1-H 2 dabch]I 2 ( 1 ) with alkali metal halide MX (M = Na, K, Cs; X = Cl, Br) at room temperature produced a series of organic-inorganic hybrid (OIH) materials [1 S ,4 S -2,5-2.2.1-H 2 dabch]NaBr 3 ( 2 ), [1 S ,4 S -2,5-2.2.1-H 2 dabch]CsCl 3 ·H 2 O ( 3 ) and [1 S ,4 S -2,5-2.2.1-H 2 dabch]KBr 3 ·H 2 O ( 4 ). The single-crystal X-ray diffraction analysis revealed that the organic-inorganic framework structures comprised of the templating ligand and alkali metal halides (NaBr, CsCl, KBr) displayed dimensions spanning from one-dimensional (1D) to three-dimensional (3D). Moreover, the results of both differential scanning calorimetry (DSC) and dielectric measurements demonstrated that compounds 1-4 displayed reversible, high-temperature phase transitions and noticeable dielectric anomalies. In addition, the temperature-dependent second harmonic generation (SHG) results revealed crystals 1 and 3 can switch from the SHG-ON to the SHG-OFF state, which was proved by the variable-temperature X-ray diffraction. This research aims to streamline the exploration of multifunctional second harmonic generation (SHG) and dielectric materials that have been synthesized using chiral ligands and alkali metals. This will provide researchers with enhanced opportunities to delve further into this specific research domain.

Reported herein is direct C(sp 3 )-H arylation of unprotected benzyl anilines and alkylarenes via consecutive photoinduced electron transfer by visible light irradiation. Reductive quenching cycles and radical-radical cross-coupling were involved, and electron paramagnetic resonance experiments provide evidence for the formation of radical intermediates formed in situ . The protocol highlights transition metal free, external oxidant free, broad substrate scope, and high efficiency (>60 examples, up to 96%).

Organic-inorganic hybrid metal halides have attracted significant attention in recent years due to their excellent optoelectronic properties and potential applications in solar cells. Herein, the organic-inorganic hybrid molecule [ N , N -dimethyl-1,3-propanediamine]SbBr 5 ( 1 ) was synthesized by reacting a long-chain organic diamine N , N -dimethyl-1,3-propanediamine with SbBr 3 as a metal halide precursor in HBr aqueous solution. Compound 1 possesses a one-dimensional chainlike structure with the second-harmonic generation switch and two continuous phase transitions above room temperature. The band gap of compound 1 is about 2.62 eV, exhibiting a semiconductive property, which may have important implications for the development of new optoelectronic devices.

A novel solid-state second harmonic generation (SHG) organic-inorganic hybrid switch [Me 3 NCH 2 CH 2 F]FeBr 4 (1) exhibits genuine three-step "on-off-on-off" SHG-switching above-room temperature, which has potential applications in multi-step optical devices.

Direct N -allylation of azoles with hydrogen evolution has been achieved through the synergistic combination of organic photocatalysis and cobalt catalysis. The protocol bypasses stoichiometric oxidants and prefunctionalization of alkenes and produces hydrogen (H 2 ) as the byproduct. This transformation highlights high step- and atom-economy, high efficiency, and broad functional group tolerance for further derivatization, which opens a door for C-N bond formation that is valuable in heterocyclic chemistry.

Switchable second harmonic generation (SHG) materials have potential applications in information storage, signal processing, and so on because they can switch between SHG-on and SHG-off states. In this work, we designed and synthesized three organic-inorganic hybrid Rb halide three-dimensional (3D) perovskite materials [1 S ,4 S 2,5-2.2.1-H 2 dabch]RbX 3 ·0.5H 2 O (X = Cl, 1 ; Br, 2 ; I, 3 ) based on the chiral 1 S ,4 S -2,5-diazabicyclo[2.2.1]heptane (1 S ,4 S -2,5-2.2.1-dabch). The selection of homochiral organic cations ensures that the compounds 1 ∼ 3 crystallize in the noncentrosymmetric and chiral space group P 2 1 2 1 2 1 , which further leads to reversible SHG responses of the three compounds. Through differential scanning calorimetry (DSC) and dielectric measurements, it revealed that the phase transition point of the compounds 1 ∼ 3 increased with RbCl, RbBr, and RbI. This is because the hydrogen interaction H···X between the inorganic framework [RbX 3 ] n and the organic cation [1 S ,4 S -2,5-2.2.1-H 2 dabch] 2+ is increased with the order of I > Br > Cl. This study can provide an effective molecular design strategy for the exploration and construction of temperature-tunable SHG switching materials.

Even though hybrid organic-inorganic perovskites (HOIPs) have been studied by many scholars in recent years, there are not many reports on three-dimensional (3D) alkali metal cesium halide perovskites. Here, we report an unprecedented 3D HOIP molecule (1,5-3.2.2-H 2 dabcn)CsBr 3 ( 1 ), in which the 3D anionic framework is constructed by corner-sharing CsBr 6 octahedra and organic cations [1,5-3.2.2-H 2 dabcn] 2+ are located in the cavities formed by the octahedra. Organic cations interact with an inorganic metal frame via two N-H···Br hydrogen bonds. Compound 1 undergoes a reversible order-disorder phase transition and exhibits switchable dielectric and second-harmonic generation (SHG) properties. Interestingly, product 1 crystallizes in a non-centrosymmetric space group Pmn 2 1 at the low-temperature phase (LTP) and transforms into a centrosymmetric space group P 2/ m at the high-temperature phase (HTP). The space group Pmn 2 1 in the LTP has a higher symmetry than P 2/ m in the HTP. This inverted symmetry breaking is very unusual.

Compared with the spherical molecule 1,4-diazoniabicyclo[2.2.2]-octane (2.2.2-dabco), 1,5-diazabicyclo[3.2.2]nonane (3.2.2-dabcn) bears a lower symmetry and larger size. As expected, reactions of 3.2.2-dabcn with rubidium halides gave two 3D molecular ferroelectrics [3.2.2-H 2 dabcn]RbX 3 (X = Br for 1; X = I for 2) with T c at 342 K (1) and 293 K (2).

An organic-inorganic hybrid molecule [3.3.0-H 2 dabco]ZnBr 4 ( 1 ) with switchable phase transition, dielectric anomaly, and second harmonic generation (SHG) effect was synthesized by reaction of 1,5-diazabicyclo[3.3.0]octane (3.3.0-dabco) with ZnBr 2 in concentrated hydrobromic acid aqueous solution. Differential scanning calorimetry (DSC) and dielectric measurements revealed that 1 exhibits a reversible high-temperature phase transition, accompanied by a distinct step-like dielectric anomaly at 373 K. Exceptionally, the single crystal structure analysis at different temperatures revealed that 1 undergoes reverse symmetry breaking during the phase transition, in which the high-symmetry space group Cc in the low temperature phase (LTP) is transformed to the low-symmetry space group P 1̅ in the high temperature phase (HTP). In addition, with the conversion from the non-centrosymmetric (NCS) to the centrosymmetric (CS) space group, the SHG of 1 can switch from SHG-ON to SHG-OFF for at least four cycles without obvious decay.

Diabetes mellitus (DM) is characterized by the irreversible destruction of insulin-secreting pancreatic β-islet cells and requires life-long exogenous insulin therapy. Umbilical cord Wharton's jelly-derived mesenchymal stem cells (WJ-MSCs) have been shown to improve islet function in animal models of diabetes. However, inadequate MSC homing to injured sites has limited their efficacy. Since efficient cell therapy heavily relies on appropriate homing to target tissues, increasing the specificity to the target organ and the extent of homing of the injected WJ-MSCs is paramount to successful clinical outcomes. Therefore, in this study, we synthesized Fe 3 O 4 @polydopamine nanoparticle (NP)-labeled MSCs and evaluated their therapeutic efficacy in a clinically relevant rat model of streptozotocin-induced diabetes using an external magnetic field. We found that NPs were successfully incorporated into WJ-MSCs and did not negatively affect stem cell properties. Magnetic targeting of WJ-MSCs contributed to long-term cell retention in pancreatic tissue and improved the islet function of diabetic rats, compared to injection of WJ-MSC alone. In addition, anti-inflammatory effects and the anti-apoptotic capacity of WJ-MSCs appeared to play a major role in the functional and structural recovery of the pancreas. Thus, therapy relying on the magnetic targeting of WJ-MSCs may serve as an effective approach for DM treatment.

Human mesenchymal stem cell (MSC)-derived exosomes (Exos) are a promising therapeutic agent for cell-free regenerative medicine. However, their poor organ-targeting ability and therapeutic efficacy have been found to critically limit their clinical applications. In the present study, we fabricated iron oxide nanoparticle (NP)-labeled exosomes (Exo + NPs) from NP-treated MSCs and evaluated their therapeutic efficacy in a clinically relevant model of skin injury. We found that the Exos could be readily internalized by human umbilical vein endothelial cells (HUVECs), and could significantly promote their proliferation, migration, and angiogenesis both in vitro and in vivo. Moreover, the protein expression of proliferative markers (Cyclin D1 and Cyclin A2), growth factors (VEGFA), and migration-related chemokines (CXCL12) was significantly upregulated after Exo treatment. Unlike the Exos prepared from untreated MSCs, the Exo + NPs contained NPs that acted as a magnet-guided navigation tool. The in vivo systemic injection of Exo + NPs with magnetic guidance significantly increased the number of Exo + NPs that accumulated at the injury site. Furthermore, these accumulated Exo + NPs significantly enhanced endothelial cell proliferation, migration, and angiogenic tubule formation in vivo; moreover, they reduced scar formation and increased CK19, PCNA, and collagen expression in vivo. Collectively, these findings confirm the development of therapeutically efficacious extracellular nanovesicles and demonstrate their feasibility in cutaneous wound repair.

Background: Hepatitis B virus (HBV) infection is a crucial medical issue worldwide. The dependence of HBV replication on host cell machineries and their co-evolutionary interactions prompt the codon usage pattern of viral genes to translation selection and mutation pressure., Objective: The evolutionary characteristics of HBV and the natural selection effects of the human genome on the codon usage characteristics were analyzed to provide a basis for medication development for HBV infection., Methods: The codon usage pattern of sequences from different HBV genotypes of our isolates and reference HBV genome sequences downloaded from the National Center for Biotechnology Information (NCBI) database were analyzed by computing the relative synonymous codon usage (RSCU), nucleotide content, codon adaptation index (CAI) and the effective number of codons (ENC)., Results: The highest ENC values were observed in the C genotypes, followed by the B genotypes. The ENC values indicated a weak codon usage bias (CUB) in HBV genome. The number of codons differentially used between the three genotypes was markedly higher than that of similarly used codons. High CAI values indicated a good adaptability of HBV to its host. The ENC plot indicated the occurrence of mutational pressure in the three genotypes. The mean Ka/Ks ratios in the three genotypes were lower than 1, which indicated a negative selection pressure. The CAI and GC3% plot indicated the existence of CUB in the HBV genome., Conclusions: Nucleotide composition, mutation bias, negative selection and mutational pressure are key factors influencing the CUB and phylogenetic diversity in HBV genotypes. The data provided here could be useful for developing drugs for HBV infection.

Mesenchymal stem cell (MSC)-based therapy has emerged as a promising therapeutic strategy for tissue regeneration and repair. However, efficient targeted delivery to specific tissues remains an open challenge. Here, we non-invasively monitored the migration of MSCs labeled with Fe3O4@polydopamine nanoparticles (Fe3O4@PDA NPs) toward laser burn injury sites in a living rat model and evaluated the effects of the labeled MSCs at the injury site. The Fe3O4@PDA NPs could be effectively incorporated into the MSCs without any negative effects on stem cell properties. Furthermore, they enhanced the migration ability of the MSCs by up-regulating the expression level of C-X-C chemokine receptor type 4 (CXCR4). They also increased the secretion of some cytokines and the expression of healing-related genes in comparison with unlabeled MSCs. Labeled MSCs were intravenously administered into injured rats, and live imaging was performed to monitor MSC migration. Fluorescent signals of the labeled MSCs appeared at burn injury lesions 1 day after injection and then gradually increased up to 7 days. After 7 days, the group injected with the labeled MSCs showed less inflammation compared with those injected with the unlabeled MSCs. Additionally, the labeled MSC group showed increased cytokines and reduced pro-inflammatory factors compared with the unlabeled MSC group. The Fe3O4@PDA NPs enhanced stromal cell-derived factor-1/CXCR4-mediated MSC migration in vivo. Thus, we demonstrated the safety, feasibility, and potential efficacy of using the Fe3O4@PDA NPs for optimizing MSC-based therapeutic strategies for burn wound healing.

Natural killer (NK)-cell-based immunotherapy has been reported to have promising prospects in the treatment of non-small cell lung cancer, one of the most common malignancies in the world. It has been proven that higher the NK cell infiltration into the tumor, the better is the curative effect. Therefore, it would be beneficial to develop a method that increases NK cell recruitment and infiltration into the tumor site. The purpose of this study was to establish an immune-cell delivery system for clear lung cancer cells based on magnetic nanoparticle (NP)-labeled NK cells that can be accumulated at the tumor site by placing a tiny external magnetic device inside animals. We developed superparamagnetic iron oxide NPs consisting of a magnetic Fe3O4 core and a shell of polydopamine (PDA) for magnetic targeting therapy. Fe3O4@PDA NPs possess favorable physiological stability and biocompatibility that facilitate their active uptake by NK cells. The biology of NK cells was not affected by the presence of NPs. In vitro and in vivo studies showed that Fe3O4@PDA NP-labeled NK cells significantly inhibited tumor growth and reduced the expression of Ki-67 and increased the apoptosis of A549 cancer cells. H&E staining showed Fe3O4@PDA NP-labeled NK cells, under a magnetic field, had higher intra-tumoral iron density and increased accumulation of CD56+ NK cells. Our results suggest that Fe3O4@PDA NPs are a promising magnetic nanomaterial that can manipulate immune cells, thereby inhibiting tumor growth.