Spin State Differentiated [3Fe-4S] Cluster Electrocatalyzes Water Oxidation Efficiently.

Though there are many synthetic iron-sulfur clusters that have been reported to show catalytic activity mimicking the natural cofactors in metalloenzymes, the influence of the spin state on the catalytic property is seldom touched. Here, a disulfide-bridged triiron(II) complex is shown, namely [Fe(Sip)][CFSO] (Fe(Sip), HSip = sulfanylpropyliminomethyl-pyridine), can efficiently electrocatalyze water oxidation with a turnover frequency of 932 s and Faraday efficiency of 86%, better than many iron-based catalysts. More importantly, the terminal low-spin (S = 0) iron(II) sites possessing a N4S2 first coordination environment, along with the synergetic catalysis of ligands, play a crucial role in the catalytic process.

Photocatalytic Reduction of CO to CO in 100%: The Synergistic Effect of Nickel and Europium in Heterometallic Clusters.

Heterometallic transition-rare earth metal (3d-4f) clusters with synergistic catalytic activity are rarely identified. Herein, two families of closely related 3d-Eu clusters were designed to analyze the role of Eu(III) ions during the photocatalytic reduction of CO into CO. The [MEu] family, where M = Co or Ni, shows much lower activity (CO production < 2078 µmol g h) compared to the [MEu] family (CO production > 5838 µmol g h).

Heterologous Expression of the Fellutanine Biosynthetic Gene Cluster and Characterization of the Dual Prenylation of cyclo(l-Trp-l-Trp) by a Single DMATS Enzyme.

2,5-Diketopiperazines (2,5-DKPs) are recognized for their structural rigidity and diverse bioactivities, making them significant in drug discovery. However, the stereochemical complexity of 2,5-DKPs presents challenges in chemical synthesis, particularly concerning indole derivatives such as indole diketopiperazines (IDKPs). Prenylation and oxidation further diversify these structures, enhancing their bioactivity and membrane affinity.

Metal-Organic Cages Assembled From {Ni} Nodes for Selective CO Reduction.

Constructing cluster-based nodes and using them as catalytic sites can bring new structure and function for metal-organic cages (MOCs). However, successful examples are very limited. Herein, we found that a 2-mercapto-5-methyl-1,3,4-thiadiazole (Hmmt) based {Ni} subunit is robust in building such MOCs.

Assembling Giant Nanoclusters as Heterogeneous Catalysts for Effectively Converting CO to CO Under Visible Light.

Heterometallic lanthanide-transition metal (3d-4f) nanoclusters with well-defined structures and multiple active sites are excellent vehicles for achieving efficient catalysis and studying heterometallic synergism. In this work, two closely related yet different high-nuclearity nanoclusters, 72-nuclear {NiRE} (1, RE = Pr, Nd, Sm, Eu, and Gd) and 111-nuclear {NiLa} (2), are synthesized using a mixed-ligand strategy. Importantly, the crystal solids of these giant coordination clusters are insoluble when soaking in HO/CHCN and can be used as heterogeneous catalysts for visible-light-driven catalytic conversion of CO to CO.

Porous 3 d-4 f Coordination Clusters for Selective Visible-Light Photocatalytic CO Reduction to CO.

We report herein two families of porous coordination clusters (PCCs) with 216 nuclearity (MRE or PCC-216MR) and 300 nuclearity (CoGd or PCC-300CG). For the first family M could be either nickel or cobalt, and RE = Pr, Nd, Sm, Eu, and Gd; while the latter features the highest nuclearity of transition-rare earth metal clusters. Characterized by their cube-like, hollow structures, these clusters exhibit the ability to absorb N and CO.

Tumor-repopulating cells evade ferroptosis via PCK2-dependent phospholipid remodeling.

Whether stem-cell-like cancer cells avert ferroptosis to mediate therapy resistance remains unclear. In this study, using a soft fibrin gel culture system, we found that tumor-repopulating cells (TRCs) with stem-cell-like cancer cell characteristics resist chemotherapy and radiotherapy by decreasing ferroptosis sensitivity. Mechanistically, through quantitative mass spectrometry and lipidomic analysis, we determined that mitochondria metabolic kinase PCK2 phosphorylates and activates ACSL4 to drive ferroptosis-associated phospholipid remodeling.

Fine Tuning Ag(I)-Sb(III) Hybrid Iodides for Light Detection.

Lead-free hybrid double perovskite iodides (HDPIs) have piqued increasing research interest due to their environmental friendliness and high stability. However, such antimony-based HDPIs with strong photocurrent response are currently very limited. Here, we successfully design and construct five Ag(I)-Sb(III)-based HDPIs using two types of cyclic aliphatic amines as A-site templates.

Modulation of the magnetic dynamics in two air-stable sulfur-ligated dysprosium complexes polymerization.

Two air-stable sulfur-ligated dysprosium(III) complexes [HN(Et)][DyNaL] (1) and [DyNaL(MeOH)(HO)] (2) based on 2-pyridinethiol 1-oxide (HL) were synthesized and structurally characterized. Discrete 1 and polymeric 2 share the same anionic unit of [DyL] with the OS coordination environment, but differ in the precise geometry with triangular dodecahedron geometry in 1 and biaugmented trigonal prism geometry in 2. The subtle change leads to observable temperature-independent relaxation for 2 while a faster relaxation with invisible peak for 1 at zero dc field.

Synthesis and Characterization of Polyimides with Naphthalene Ring Structure Introduced in the Main Chain.

In this paper, a new aromatic diamine monomer 4,4'-(2,6-naphthalenediyl)bis[benzenamine]) (NADA) was synthesized and a series of modified PI films containing naphthalene ring structure obtained by controlling the molar ratio of NADA monomer, ternary polymerization with 4,4'-oxydianiline (ODA), and pyromellitic dianhydride (PMDA). The effects of the introduction of the naphthalene ring on the free volume and various properties of PI were investigated by molecular dynamic simulations. The results show that the comprehensive properties of the modified films are all improved to some extent, with 5% thermal weight loss temperature (T) of 569 °C, glass transition temperature (Tg) of 381 °C, tensile strength of 96.

Development and Validation of a Novel Ferroptosis-Related Gene Signature for Predicting Prognosis and the Immune Microenvironment in Gastric Cancer.

Ferroptosis is a mode of regulated cell death that depends on iron and plays pivotal roles in regulating various biological processes in human cancers. However, the role of ferroptosis in gastric cancer (GC) remains unclear. In our study, a total of 2721 differentially expressed genes (DEGs) were filtered based on The Cancer Genome Atlas (TCGA) ( = 375) dataset.

Ambiphilic Reactivity of Vinyl Pd-Oxyallyl for Expeditious Construction of Highly Functionalized Cyclooctanoids.

We report the catalytic generation of a vinyl Pd-oxyallyl that dimerizes regiospecifically to form highly functionalized nonbridged cyclooctanoids. Such compounds are otherwise synthetically challenging, but highly useful in synthesis. This vinyl Pd-oxyallyl species demonstrates both electrophilic and nucleophilic properties.

Magnetic Anisotropy: Structural Correlation of a Series of Chromium(II)-Amidinate Complexes.

Systematic substituent variations on amidinate ligands bring delicate changes of CrN coordination in a family of chromium(II) complexes with the common formula of Cr(RNC(CH)NR), where R = Pr (), Cy (), Dipp (Dipp = 2, 6-diisopropylphenyl) (), and Bu (). With the largest substituent group, shows the largest distortion of the N coordination geometry from square-planar to seesaw shape, which leads to its field-induced single-molecule magnet (SMM) behavior. This is an indication that has the strongest axial magnetic anisotropy and/or optimized magnetic relaxation process.

Highly Emissive Perylene Diimide-Based Metallacages and Their Host-Guest Chemistry for Information Encryption.

Here we report two highly emissive perylene diimide (PDI)-based metallacages and explore their complexation with polycyclic aromatic hydrocarbons, such as pyrene, triphenylene, and perylene. The fluorescence quantum yields of metallacages exceed 90% and their binding constants with perylene can reach as high as 2.41 × 10 M in acetonitrile.

A Local D Symmetric Dysprosium(III) Single-Molecule Magnet with an Energy Barrier Exceeding 2000 K*.

Three six-coordinate Dy single-molecule magnets (SMMs) [Dy(O Bu) (L) ] with local D symmetry are obtained by optimizing the equatorial ligands. One of the compounds with L=4-phenylpyridine shows an energy barrier (U ) of 2075(11) K, which is the third largest U , and the first U >2000 K for SMMs with axial-type symmetry so far. Ab initio analysis indicates that the exceptional uniaxial magnetic anisotropy is deeply related to the axially compressed octahedral geometry.

Terbium-fluorido cluster: an energy cage for photoluminescence.

We report here that energy migration during luminescence can be extremely minimized by caging the fluorescent centers in a molecular cluster of [Tb6(μ3-F)8(piv)10(Hpiv)4DMF]·xDMF·yH2O 1. Experimental and theoretical simulations reveal that bonding terbium with fluoride is the key to reducing the non-radiative multi-phonon relaxation processes, which is disparate to the common hydroxy-based lanthanide clusters.

Air-Stable Hexagonal Bipyramidal Dysprosium(III) Single-Ion Magnets with Nearly Perfect D Local Symmetry.

Eight-coordinated Dy centres with D symmetry are expected to act as high-performance single-molecule magnets (SMMs) due to the simultaneous fulfilment of magnetic axiality and a high coordination number (a requisite for air stability). But the experimental realization is challenging due to the requirement of six coordinating atoms in the equatorial plane of the hexagonal bipyramid; this is usually too crowded for the central Dy ion. Here a hexaaza macrocyclic Schiff base ligand and finetuned axial alkoxide/phenol-type ligands are used to show that a family of hexagonal bipyramidal Dy complexes can be isolated.

Correlating magnetic anisotropy with the subtle coordination geometry variation of a series of cobalt(ii)-sulfonamide complexes.

Systematic substitution on the N-(pyridine-2-ylmethyl)-sulfonamide ligand leads to the subtle variation of the CoN4 coordination geometry in a series of cobalt(ii) complexes sharing the common formula of Co[R1(C6N2H5)R2]2, where R1 = H, R2 = 4-tert-butylphenylsulfonyl (tBuphs) 1, R2 = 5-(dimethylamino)naphthalen-1-ylsulfonyl (DNps) 2, R2 = mesitylsulfonyl (Ms) 3, R2 = tosyl (Tos) 4, and R2 = naphthalen-1-ylsulfonyl (Nps) 5; R1 = Me, R2 = tBuphs 6. Magnetic studies show that the axial zero-field splitting parameter (D) is subtlely correlated with the coordination geometric variation subjected to the peripheral substituted groups. Specifically, the distortion from the ideal tetrahedral geometry (Td symmetry) to the seesaw geometry (D2d symmetry) increases uniaxial magnetic anisotropy.

Quantum Monte Carlo simulations of a giant {NiGd} cage with a S = 91 spin ground state.

The detailed analysis of magnetic interactions in a giant molecule is difficult both because the synthesis of such compounds is challenging and the number of energy levels increases exponentially with the magnitude and number of spins. Here, we isolated a {NiGd} nanocage with a large number of energy levels (≈5 × 10) and used quantum Monte Carlo (QMC) simulations to perform a detailed analysis of magnetic interactions. Based on magnetization measurements above 2 K, the QMC simulations predicted very weak ferromagnetic interactions that would give a record S = 91 spin ground state.

Hydrogel with Ultrafast Self-Healing Property Both in Air and Underwater.

Self-healing hydrogels have a great potential application in 3D printing, soft robotics, and tissue engineering. There have been a large number of successful strategies for developing hydrogels that exhibit rapid and autonomous recovery. However, developing a gel with an excellent self-healing performance within several seconds is still an enormous challenge.

Quantum Monte Carlo Simulations and High-Field Magnetization Studies of Antiferromagnetic Interactions in a Giant Hetero-Spin Ring.

Chromium lanthanide heterometallic wheel complexes {Cr Ln } (Ln=Gd, Dy and Y) with alternating metal centres are presented. Quantum Monte Carlo simulations reveal antiferromagnetic exchange-coupling constants with an average of 2.1 K within the {Cr Gd } wheel, which leads to a large ground spin state (S =16) that is confirmed by magnetization studies up to 20 Tesla.

Filling the Missing Links of M Prototype 3d-4f and 4f Cyclic Coordination Cages: Syntheses, Structures, and Magnetic Properties of the NiLn and the Er Wheels.

In this paper, we proposed a number rule for 3d-4f and 4f cyclic coordination cages (CCCs); that is, CCCs consisting of vertex-sharing M(μ-OH) (M = 3d transition metal or 4f lanthanide ions) units should have 3 × n metal centers (abbreviated M), where n represents the number of the M(μ-OH) subunits. Under this number rule we reasoned that some species of CCCs, for example, the pentadecanuclear 3d-4f wheel and the pure 4f wheels with 9 or 18 centers, should practically have existed. However, there are no such complexes reported in the literature.