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Polymetallic complexes with covalently bridged metal centers that interact magnetically are important in the molecular magnetism field, with binuclear compounds receiving special attention because they represent the simplest type of multinuclear species with covalently bridged metal centers. Herein, we report the synthesis and properties of two new binuclear FeII complexes, namely, {[Fe(abpt-TPE)(NCS)2]2(bpym)}·2MeOH·2MeCN (1) and {[Fe(abpt-TPE)(NCS)2]2(bpym)}·2CH2Cl2 (2) (bpym = 2,2′-bipyrimidine). The crystal structure is analyzed at different temperatures, and its properties are analyzed by variable-temperature magnetic susceptibility and variable-temperature fluorescence emission spectroscopy tests. Variable-temperature magnetic susceptibility measurements of two binuclear compounds show different types of magnetic behavior. Complex 1 exhibits two-step spin transition behavior with an intermediate state near 150 K (Tc1 = 191 K, Tc2 = 111 K); 1 undergoes an [LS–LS] ↔ [LS–HS] ↔ [HS–HS] spin transition during thermal induction. On the other hand, complex 2 exhibits intramolecular antiferromagnetic coupling, with J = −0.47 cm−1. The analysis of correlations between the structural characteristics and different types of magnetic behaviors for two binuclear complexes, revealed that the different magnetic behaviors shown by the two complexes are attributable to different degrees of [FeN6] octahedral distortion caused by different lattice solvents, ligand strain and crystal stacking. [ABSTRACT FROM AUTHOR]

HtrA serine peptidase 3 (HTRA3) participates in multiple signal pathways and plays an important regulatory role in various malignancies; however, its role on prognosis and immune infiltrates in gastric cancer (GC) remains unclear. The study investigated HTRA3 expression in tumor tissues and its association with immune infiltrates, and determined its prognostic roles in GC patients. Patients with GC were collected from the cancer genome atlas (TCGA). We compared the expression of HTRA3 in GC and normal gastric mucosa tissues with Wilcoxon rank sum test. And logistic regression was used to evaluate the relationship between HTRA3 and clinicopathological characters. Gene ontology (GO) term analysis, Gene set enrichment analysis (GSEA), and single-sample Gene Set Enrichment Analysis (ssGSEA) was conducted to explain the enrichmental pathways and functions and quantify the extent of immune cells infiltration for HTRA3. Kaplan-Meier analysis and Cox regression were performed to evaluate the correlation between HTRA3 and survival rates. A nomogram, based on Cox multivariate analysis, was used to predict the impact of HTRA3 on prognosis. High HTRA3 expression was significantly correlated with tumor histological type, histological grade, clinical stage, T stage, and TP53 status (P < 0.05). HTRA3-high GC patients had a lower 10-year progression-free interval [PFI; hazard ratio (HR): 1.46; 95% confidence interval (CI): 1.02–2.08; P = 0.038], disease-specific survival (DSS; HR: 1.65; CI: 1.08–2.52; P = 0.021) and overall survival (OS; HR: 1.59; CI: 1.14–2.22; P = 0.006). Multivariate survival analysis showed that HTRA3 was an independent prognostic marker for PFI (HR: 1.456; CI: 1.021–2.078; P = 0.038), DSS (HR: 1.650; CI: 1.079–2.522; P = 0.021) and OS [hazard ratio (HR): 1.590; 95% confidence interval (CI):1.140–2.219; P = 0.006]. The C-indexes and calibration plots of the nomogram based on multivariate analysis indicated an effective predictive performance for GC patients. GSEA showed that High HTRA3 expression may activate NF-κB pathway, YAP1/WWTR1/TAZ pathway, and TGFβ pathway. There was a negative correlation between the HTRA3 expression and the abundances of adaptive immunocytes (T helper cell 17 cells) and a positive correlation with abundances of innate immunocytes (natural killer cells, macrophages etc.). HTRA3 plays a vital role in GC progression and prognosis and could be a moderate biomarker for prediction for survival after gastrectomy. [ABSTRACT FROM AUTHOR]

In this study, a new dinuclear cobalt(II)–radical complex [Co2(3,5-DBSQ)4(bpym)]·(3,5-DBCatH2)4 (1) (3,5-DBSQ = 3,5-di-tert-butylsemiquinone, 3,5-DBCatH2 = 3,5-di-tert-butylcatecholato, bpym = 2,2′-bipyrimidine) was synthesized and characterized using single-crystal X-ray crystallography. Simulated results indicated relatively strong antiferromagnetic exchange coupling between cobalt(II) centers and semiquinone radical ligands. [ABSTRACT FROM AUTHOR]

We report three self‐assembled iron complexes that comprised an anti‐parallel open form (o‐Lanti), a parallel open form (o‐Lsyn), and a closed form (c‐L) of diarylethene conformers. Under kinetic control, FeII2(o‐Lanti)3 was isolated, which exhibited a dinuclear structure with diamagnetic properties. Under light‐irradiation control, FeII2(c‐L)3 was prepared and exhibited paramagnetism and spin‐crossover behaviour. Under thermodynamic control and in the presence of indispensable [FeIII(Tp*)(CN)3]−, FeII2(o‐Lanti)3 and FeII2(c‐L)3 transformed into tetranuclear FeIII2FeII2(o‐Lsyn)2, which exhibited complete spin‐crossover behaviour at T1/2=353 K. [ABSTRACT FROM AUTHOR]

A neutral mononuclear FeIII complex [FeIII(H-5-Br-thsa-Me)(5-Br-thsa-Me)]⋅H2O ( 1; H2-5-Br-thsa-Me=5-bromosalicylaldehyde methylthiosemicarbazone) was prepared that exhibited a three-step spin-crossover (SCO) with symmetry breaking and a 14 K hysteresis loop owing to strong cooperativity. Two ordered intermediate states of 1 were observed, 4HS-2LS and 2HS-4LS, which exhibited reentrant phase-transition behavior. This study provides a new platform for examining multistability in SCO complexes. [ABSTRACT FROM AUTHOR]

The mononuclear ferric compound Fe(H-5-Cl-thsa-Me)(5-Cl-thsa-Me)·H2O (1) was synthesized and characterized using powder/single-crystal X-ray diffraction, Mössbauer spectroscopy, differential scanning calorimetry (DSC), and magnetic susceptibility measurements. This photo-responsive compound shows reversible, two-step spin-crossover behaviour. Moreover, dielectric anomalies were observed during the spin transitions, demonstrating the multifunctional properties of compound 1. [ABSTRACT FROM AUTHOR]

Spin doctor: A mononuclear ferric complex [Fe(H‐5‐Br‐thsa)(5‐Br‐thsa)]⋅H2O (1) (H2‐5‐Br‐thsa=5‐bromo‐2‐hydroxybenzylidene)hydrazinecarbothioamide) was synthesized and its magnetic properties and structure were investigated by DFT calculations. This complex shows unprecedented reversible, six/five‐step spin‐crossover behavior accompanied by symmetry breaking. More importantly, each step in the multi‐step transition was successfully characterized by single‐crystal X‐ray diffraction. [ABSTRACT FROM AUTHOR]

2-(2,2′ : 6′,2″-Terpyridin-4′-yl)phenol has been prepared with an improved one-pot method. The reaction between the ligand and MnCl2 in ethanol at ambient or hydrothermal conditions afforded dichlorido[2-(2,2′ : 6′,2″-terpyridin-4′-yl)phenol-κ3 N,N′,N″]manganese(II) and dichloridobis[µ-2-(2,2′ : 6′,2″-terpyridin-4′-yl)phenolate-κ3 N,N′,N″-κO]dimanganese(II), respectively. Face-to-face π–π stacking interactions between the pyridine rings play a crucial role in supramolecular networks of both complexes. Both complexes display weaker photoluminescence than the free ligand and the dinuclear complex luminescence was stronger than the mononuclear one. [ABSTRACT FROM PUBLISHER]

Reacting lanthanide nitrates with 2,5-pyrazinedicarboxylic acid (2,5-pzdcH2) and oxalic acid (oxH2) hydrothermally at 140 °C yielded a series of MOFs with 1D nano-sized channels, [Ln(2,5-pzdc)(ox)0.5(H2O)2]·4.5H2O (1-Ln; Ln = Nd, Sm, Eu, Gd, Tb, Dy), different from previously reported ultra-microporous [Ln(2,5-pzdc)1.5(H2O)3]·0.5H2O. While the oxalic acid was replaced by other dicarboxylic acids like terephthalic acid, malonic acid, glutaric acid, or pyrazole-3,5-dicarboxylic acid, obtained was a novel series of 1D polymers, [Ln(2,5-pzdc)0.5(2,6-pzdc)(H2O)3] (2-Ln; Ln = Pr, Sm, Eu, Tb; 2,6-pzdc2−= 2,6-pyrazinedicarboxylate), with 2,6-pzdc2−formed in situby formal carboxyl transfer. This represents the first example of carboxyl transfer either in coordination compounds or in hydrothermal synthesis. The Eu and Tb complexes in these two series emit strong ligand sensitized f–fluminescence. [ABSTRACT FROM AUTHOR]

Comprehensive Summary Spin crossover (SCO), characterized by distinct high‐spin (HS) and low‐spin (LS) states, has potential applications in memory, electronic, and electroluminescent devices. The OFF/ON switching of SCO is crucial for obtaining bistable magnetic properties. However, there are few strategies for achieving this switching. Herein, based on a ligand chemical doping strategy, we report an Fe(III) solid solution that can be prepared using a ligand chemical doping strategy, enabling not only the OFF/ON switching of SCO but also the fine‐tuning of the spin transition temperature (Tc) within a 45 K range near room temperature. The experimental results show that when the polar ligand doping ratio reaches 20%, SCO behavior is triggered, and the crystal phase transforms significantly, becoming loose and flexible. Furthermore, Tc can be continuously regulated as the ligand‐doping ratio increases. Density functional theory (DFT) calculations reveal that solid packing‐induced molecular distortion blocks SCO, whereas loosely flexible packing triggers SCO via fluorinated ligand chemical doping. [ABSTRACT FROM AUTHOR]

Organic radicals are widely used as linkers or ligands to synthesize molecular magnetic materials. However, studies regarding the molecular anisotropies of radical-based magnetic materials and their multifunctionalities are rare. Herein, a photoisomerizable diarylethene ligand was used to form {[Co III (3,5-DTSQ ·- )(3,5-DTCat 2- )] 2 (6F-DAE-py 2 )}·3CH 3 CN·H 2 O ( o-1 ·3CH 3 CN·H 2 O, 6F-DAE-py 2  = 1,2-bis(2-methyl-5-(4-pyridyl)-3-thienyl)perfluorocyclopentene), a valence-tautomeric (VT) coordination polymer. We directly observed dual radicals for a single crystal using high-field/-frequency (∼13.3 T and ∼360 GHz) electron paramagnetic resonance (EPR) spectroscopy along the c -axis, which was further confirmed by angle-dependent Q-band EPR spectroscopy. Moreover, a conductive anomaly close to the VT transition temperature was observed only when probes were attached at the ab plane of the single crystal, indicative of synergy between valence tautomerism and conductivity. Structural anisotropy studies and density functional theory (DFT) calculations revealed that this synergy is due to electron transfer associated with valence tautomerism. This study presents the first example of dual-radical-based molecular anisotropy and charge-transfer-induced conductive anisotropy in a photoswitchable coordination polymer., (© The Author(s) 2023. Published by Oxford University Press on behalf of China Science Publishing & Media Ltd.)

Gastric cancer (GC) is one of the most common cancers in the world. The cathepsin F (CTSF) gene has recently been found to participate in the progression of several types of cancer. However, the clinical characteristics and function of CTSF in GC as well as its molecular mechanisms are not clear. Six GC cell lines and 44 paired adjacent noncancerous and GC tissue samples were used to assess CTSF expression by quantitative polymerase chain reaction (qPCR). We used lentivirus-mediated small hairpin RNA (Lenti-shRNA) against CTSF to knock down the expression of CTSF in GC cells. Western blot and qPCR were used to analyze the mRNA and related protein expression. The biological phenotypes of gastric cells were examined by cell proliferation and apoptosis assays. Microarray-based mRNA expression profile screening was also performed to evaluate the potential molecular pathways in which CTSF may be involved. The CTSF mRNA level was associated with tumor differentiation, depth of tumor invasion, and lymph node metastasis. Downregulation of CTSF expression efficiently inhibited apoptosis and promoted the proliferation of GC cells. Moreover, a total of 1,117 upregulated mRNAs and 1,143 downregulated mRNAs were identified as differentially expressed genes (DEGs). Further analysis identified the involvement of these mRNAs in cancer-related pathways and various other biological processes. Nine DEGs in cancer-related pathways and three downstream genes in the apoptosis pathway were validated by Western blot, which was mainly in agreement with the microarray data. To our knowledge, this is the first report investigating the effect of CTSF on the growth and apoptosis in GC cells and its clinical significance. The CTSF gene may function as a tumor suppressor in GC and may be a potential therapeutic target in the treatment of GC.

A neutral mononuclear Fe(III) complex [Fe(III) (H-5-Br-thsa-Me)(5-Br-thsa-Me)]⋅H2 O (1; H2 -5-Br-thsa-Me=5-bromosalicylaldehyde methylthiosemicarbazone) was prepared that exhibited a three-step spin-crossover (SCO) with symmetry breaking and a 14 K hysteresis loop owing to strong cooperativity. Two ordered intermediate states of 1 were observed, 4HS-2LS and 2HS-4LS, which exhibited reentrant phase-transition behavior. This study provides a new platform for examining multistability in SCO complexes., (© 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)

In the title compound, C20H13N5O2, the two pyrazine rings are nearly coplanar with the central pyridine ring, forming dihedral angles of 2.21 (9) and 4.57 (9)°. In contrast, the strong steric hindrance caused by the ortho-carboxyl group on the phenyl ring makes this ring rotate out of the attached pyridine ring plane by 52.60 (9)°. The carboxyl group is twisted from the phenyl ring by 22.6 (1)°. In the crystal, aromatic π-π stacking inter-actions [centroid-centroid distances = 3.9186 (4) and 3.9794 (5) Å] occur between the anti-parallel mol-ecules, generating infinite chains along [100]. O-H⋯O hydrogen bonds connect the chains, leading to the formation of a two-dimensional supra-molecular network parallel to (010). Inter-molecular C-H⋯N hydrogen bonds are also observed.

In the title compound, C12H6N2O2·C2H5OH, the mol-ecule of the 1,10-phenanthroline-5,6-dione is approximately planar, with a maximum deviation of 0.051 (1) Å. In the crystal, mol-ecules are linked by O-H⋯N and weak C-H⋯O hydrogen bonds, forming supra-molecular chains propagating along [110]. π-π stacking inter-actions are observed between the pyridine rings of neighbouring chains, the centroid-centroid separations being 3.6226 (11) and 3.7543 (11) Å.

In the title complex, [Fe(NCS)2(C18H18N4)], the Fe(II) cation is chelated by a tris-(2-pyridyl-meth-yl)amine ligand and coordin-ated by two thio-cyanate anions in a distorted N6 octa-hedral geometry. In the crystal, weak C-H⋯S hydrogen bonds and π-π stacking inter-actions between parallel pyridine rings of adjacent mol-ecules [centroid-centroid distance = 3.653 (3) Å] link the mol-ecules into a two-dimensional supra-molecular architecture. The structure contains voids of 124 (9) Å(3), which are free of solvent molecules.

Spin doctor: A mononuclear ferric complex [Fe(H-5-Br-thsa)(5-Br-thsa)]⋅H2O (1) (H2-5-Br-thsa = 5-bromo-2-hydroxybenzylidene)hydrazinecarbothioamide) was synthesized and its magnetic properties and structure were investigated by DFT calculations. This complex shows unprecedented reversible, six/five-step spin-crossover behavior accompanied by symmetry breaking. More importantly, each step in the multi-step transition was successfully characterized by single-crystal X-ray diffraction., (Copyright © 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)

The three-dimensional polymeric title compound, {[Zn(C(9)H(4)N(2)O(4))]·H(2)O}(n), contains one crystallographically independent Zn(II) atom, one fully deprotonated 1H-benzimid-azole-5,6-dicarboxyl-ate (bdc) ligand and one uncoordinated water mol-ecule. The Zn(II) atom is four-coordinated by three O atoms and one N atom from the bdc ligands, giving a distorted tetra-hedral coordination geometry. The uncoordinated water mol-ecule is bound to the main structure through a strong bdc-water N-H⋯O hydrogen bond, and two much weaker water-bdc O-H⋯O inter-actions.