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The development of novel metal–organic frameworks (MOFs) as efficient photocatalysts for hydrogen peroxide production from water and oxygen is particularly interesting, yet remains a challenge. Herein, we have prepared four cyclic trinuclear units (CTUs) based MOFs, exhibiting good light absorption ability and suitable band gaps for photosynthesis of H2O2. However, Cu‐CTU‐based MOFs are not able to photocatalyzed the formation of H2O2, while the alteration of metal nodes from Cu‐CTU to Ag‐CTU dramatically enhances the photocatalytic performance for H2O2 production and the production rates can reach as high as 17476 μmol g−1 h−1 with an apparent quantum yield of 4.72 %, at 420 nm, which is much higher than most reported MOFs. The photocatalytic mechanism is comprehensively studied by combining the isotope labeling experiments and DFT calculation. This study provides new insights into the preparation of MOF photocatalysts with high activity for H2O2 production through molecular engineering. [ABSTRACT FROM AUTHOR]

Owing to well‐defined structure as well as easy synthesis and modification, metal‐organic frameworks (MOFs) have emerged as promising catalysts for tandem reactions. In this article, we aim to summarize the development of multifunctional MOFs, including mixed metal MOFs, MOFs that are synergistically catalyzed by metal nodes and organic linkers, MOFs loaded with metal nanoparticles, etc, as heterogenous catalysts for tandem reactions over the past five years. This concept briefly discusses on present challenges, future trends, and prospects of multifunctional MOFs catalysts in tandem reactions. [ABSTRACT FROM AUTHOR]

By blending materials such as boron nitride nanosheets (BNNSs), S-BN and EP, hot pressing is used to realize the layered distribution of BNNSs and S-BN fillers in the composite material, thereby forming a composite material with a sandwich structure, a horizontal and vertical heat conduction network, and improving performance of composite materials. In this paper, in order to explore the regulation of the influence of the change of objective factor variables on the thermal conductivity and electrical insulation properties of composite materials, BNNSs and S-BN are used as the thermally conductive fillers of each layer, and EP is used as the matrix to realize the preparation of multilayer composites by high temperature and hot pressing. By changing the content of S-BN filler in the middle layer, the number of layers of the composite material and the curing temperature of the composite material, the effects of the changes of the three objective factors on the microstructure, thermal conductivity, variable temperature conductance, dielectric, breakdown, DSC and infrared thermal imaging of composite materials are explored respectively. The results show that the multilayer structure ensures good bonding. As the content, number of layers and curing temperature increase, the thermal conductivity gradually raises to 2.64 W/(m·K), which is also proved by DSC and infrared thermal imaging. Composite materials also ensure considerable breakdown strength, control the preparation cost, reduce the preparation difficulty and expand the practicability of thermal insulation materials in the thermal conductivity field. Highlights • Form a composite material with a sandwich structure, a horizontal and vertical heat conduction network. • By changing three objective factors on the microstructure, Properties of composite materials are explored respectively. • The thermal conductivity gradually raises to 2.64 W/(m·K). • Composite materials also ensure considerable breakdown strength (insulation), control the preparation cost. • Expand the practicability of thermal insulation materials in the thermal conductivity field. [ABSTRACT FROM AUTHOR]

The development of energy‐saving technology for the efficient separation of olefin and paraffin is highly important for the chemical industry. Herein, we report a self‐assembled Fe4L6 capsule containing a hydrophobic cavity, which can be used to encapsulate and separate propylene/propane. The successful encapsulation of propylene and propane by the Fe4L6 cage in a water solution was documented by NMR spectroscopy. The binding constants K for the Fe4L6 cage toward propylene and propane were determined to be (5.0±0.1)×103 M−1 and (2.1±0.7)×104 M−1 in D2O at 25 °C, respectively. Experiments and theoretical studies revealed that the cage exhibited multiple weak interactions with propylene and propane. The polymer‐grade propylene (>99.5 %) can be obtained from a mixture of propylene and propane by using the Fe4L6 cage as a separation material in a U‐shaped glass tube. This work provides a new strategy for the separation of olefin/paraffin. [ABSTRACT FROM AUTHOR]

The development of efficient, recyclable and low‐cost heterogeneous catalysts for conversion of carbon dioxide (CO2) into epoxides is highly desired, yet remain a challenge. Herein, we have prepared three two‐dimensional (2D) copper(I) cyclic trinuclear units (Cu(I)‐CTUs) based covalent metal–organic frameworks (CMOFs), namely JNM‐13, JNM‐14, and JNM‐15, via a one‐pot reaction by combination of coordination and dynamic covalent chemistry. Among them, JNM‐15 contained the highest density of copper catalytic sites, and exhibited the highest capacity for adsorption of CO2. More interestingly, JNM‐15 delivered the highest catalytic activity for cycloaddition of CO2 to epoxides with good yields (up to 99 %), good substrate compatibility (11 examples) and reusability (four catalytic cycles) under mild condition. [ABSTRACT FROM AUTHOR]

Owing to the wide and growing demand for primary alcohols, the development of efficient catalysts with high regioselectivity remains a worthwhile pursuit. However, according to Markovnikov's rule, it is a challenge to obtain primary alcohols with high yields and regioselectivity from terminal alkenes or alkynes. Herein, we report the synthesis of a photosensitizing two‐dimensional (2D) metal–organic framework (MOF) from cyclic trinuclear copper(I) units (Cu‐CTUs) and a boron dipyrro‐methene (Bodipy) ligand. The MOF features broadband light absorption, excellent photoinduced charge separation efficiency, and photochemical properties. By integrating the copper‐catalyzed hydroboration and photocatalyzed aerobic oxidation, it can catalyze terminal alkenes and alkynes to produce primary alcohols via a one‐pot tandem reaction with excellent regioselectivity, good overall yields in two‐step reactions (up to 85 %), broad substrate compatibility (32 examples) and good reusability under mild conditions. [ABSTRACT FROM AUTHOR]

Covalent organic frameworks (COFs) as metal‐free photocatalysts have attracted extensive interest. However, the organic transformations photocatalyzed by COFs under mild conditions remain a challenge. Herein, a boron‐dipyrromethene (BODIPY) based 1D COF, namely JNM‐12, was facilely constructed by Schiff‐base condensation reaction. JNM‐12 exhibited strong visible‐light harvesting abilities and suitable photocatalysis energy potentials, enabling the activation of O2 to superoxide anions (O2⋅−) and singlet oxygen (1O2) under visible light irradiation. Benefiting from these properties, JNM‐12 delivered excellent photocatalytic activity in the O2⋅−‐mediated oxidative coupling of amines and 1O2‐engaged aerobic oxidation of enamines. Our work paves a new way for synthesis of COFs as efficient, economical, and green photocatalysts for organic synthesis. [ABSTRACT FROM AUTHOR]

Porous liquids (PLs) have improved the understanding ofthe porous properties of matter; however, rational tuning ofthe viscosities and gas absorption properties ofPLs lag far behind the explosive growth of PL applications. Herein, neat molecular PLs are constructed by grafting polymers onto the surface of 2 nm molecular nanocages with precisely tuned graft densities and molecular weights Mws. The flowability ofthe PLs showed a non-monotonic dependence on the Mw of the polymers due to the interplay between the surface confinement effect and polymer chain entanglements, enabling optimization of their viscosities, similar to those of conventional liquids. The surface layer dynamics and gas absorption kinetics are quantified, correlation between the two properties is confirmed, and gas permeation process is regulated by surface layer dynamics. From the understanding of the structure-property relationship, the surface layer grafting densities are tuned to promote surface layer dynamics to achieve improved gas sorption performance. [ABSTRACT FROM AUTHOR]

The synthesis of atomically precise copper nanoclusters (Cu‐NCs) with high chemical stability is a prerequisite for practical applications, yet still remains a long‐standing challenge. Herein, we have prepared a pyrazolate‐protected Cu‐NC (Cu8), which exhibited exceptional chemical stability either in solid‐state or in solution. The crystals of Cu8 are still suitable for single crystal X‐ray diffraction analysis even after being treated with boiling water, 8 wt % H2O2, high concentrated acid (1 M HCl) or saturated base (≈20 M KOH), respectively. More importantly, the structure of Cu8 in solution also remained intact toward oxygen, organic acid (100 eq. HOAc) or base (400 eq. dibutylamine) confirmed by 1H NMR and UV/Vis analysis. Taking advantage of high alkali‐resistant, Cu8 illustrates excellent catalytic activity for the synthesis of indolizines, and it can be reused for at least 10 cycles without losing catalytic performance. [ABSTRACT FROM AUTHOR]

Facile tailoring of photosensitizers (PSs) with advanced and synergetic properties is highly expected to broaden and deepen photodynamic therapy (PDT) applications. Herein, a catalyst‐free thiol–yne click reaction was employed to develop the sulfur atom‐based PSs by using the in situ formed sulfur "heavy atom effect" to enhance the intersystem crossing (ISC), while such an effect can be remarkably magnified by the polymerization. The introduction of a tetraphenylpyrazine‐based aggregation‐induced emission (AIE) unit was also advantageous in PS design by suppressing their non‐radiative decay to facilitate the ISC in the aggregated state. Besides, the resulting sulfur atom electron donor, together with a double‐bond π bridge and AIE electron acceptor, created a donor‐π‐acceptor (D‐π‐A) molecular system with good two‐photon excitation properties. Combined with the high singlet oxygen generation efficiency, the fabricated polymer nanoparticles exhibited an excellent in vitro two‐photon‐excited PDT towards cancer cells, therefore possessing a huge potential for the deep‐tissue disease therapy. [ABSTRACT FROM AUTHOR]

Controlled-release urea is considered to enhance crop yields while reducing labor costs from fertilizer dressing, but the impacts can range widely depending on water availability in soil. Therefore, we conducted a 3-yr field study to evaluate the potential role of controlled-release urea in improving productivity and resource use efficiency of maize in semiarid areas in China. Treatments were established as two mulching modes (plastic film mulching [FM] and no mulching [NM]) and three nitrogen application modes (no nitrogen fertilizer [CK], a 1:2 ratio of controlled-release urea to common urea [CRU], and common urea only [U]). Higher temperature and soil water content under FM treatments significantly accelerated maize growth and development, as indicated in terms of a larger leaf area index before silking, greater biomass accumulation, and greater grain yield. More robust plants with controlled-release urea under mulching can better absorb and utilize deep soil water to increase water use efficiency (WUE). Mean shoot biomass, grain yield, and WUE during the three experimental years were 35.3, 19.0, and 12.4% higher in mulching with CRU treatments than in NM with controlled-release urea treatments, respectively. Significant interactions existed for yield and WUE among surface mulching (SM), nitrogen fertilizer (NF), and sampling year (Y) in the three experimental years, except for SM x NF for WUE. These results demonstrate that a mixture of controlled-release urea and U at an appropriate ratio under SM can provide a better water/temperature/nitrogen conditions for maize growth to realize relatively high yield with labor and time savings in semiarid farmland. [ABSTRACT FROM AUTHOR]

Anti-Markovnikov Selectivity, Covalent Metal-Organic Frameworks, Primary Alcohols, Tandem Reaction Keywords: Anti-Markovnikov Selectivity; Covalent Metal-Organic Frameworks; Primary Alcohols; Tandem Reaction EN Anti-Markovnikov Selectivity Covalent Metal-Organic Frameworks Primary Alcohols Tandem Reaction 1 1 1 08/25/23 20230828 NES 230828 B A photosensitizing b covalent metal-organic framework (CMOF) was prepared as a tandem reaction catalyst by Guo-Hong Ning, Dan Li, and co-workers in their Research Article (e202306497). Back Cover: A Photosensitizing Metal-Organic Framework as a Tandem Reaction Catalyst for Primary Alcohols from Terminal Alkenes and Alkynes (Angew. [Extracted from the article]

By combining Cu-CTUs as metal-catalytic sites and Bodipy linkers as photosensitizers, this CMOF can catalyze terminal alkenes and alkynes to produce primary alcohols via one-pot tandem reactions with excellent regioselectivity, good overall yields for two-step reactions, broad substrate compatibility and good reusability under mild conditions. Keywords: Anti-Markovnikov Selectivity; Covalent Metal-Organic Frameworks; Primary Alcohols; Tandem Reaction EN Anti-Markovnikov Selectivity Covalent Metal-Organic Frameworks Primary Alcohols Tandem Reaction 1 1 1 08/23/23 20230828 NES 230828 B A photosensitizing b covalent metal-organic framework (CMOF) was prepared as a tandem reaction catalyst by Guo-Hong Ning, Dan Li, and co-workers in their Research Article (e202306497). Anti-Markovnikov Selectivity, Covalent Metal-Organic Frameworks, Primary Alcohols, Tandem Reaction. [Extracted from the article]

Rab GTPases are required for vesicle-vacuolar fusion during vacuolar biogenesis in fungi. To date, little is known about the biological functions of the Rab small GTPase components in Magnaporthe oryzae. In this study, we investigated MoYpt7 of M. oryzae, a homologue of the small Ras-like GTPase Ypt7 in Saccharomyces cerevisiae. Cellular localization assays showed that MoYpt7 was predominantly localized to vacuolar membranes. Using a targeted gene disruption strategy, a MoYPT7 mutant was generated that exhibited defects in mycelial growth and production of conidia. The conidia of the MoYPT7 mutant were malformed and defective in the formation of appressoria. Consequently, the MoYPT7 mutant failed to cause disease in rice and barley. Furthermore, the MoYPT7 mutant showed impairment in autophagy, breached cell wall integrity, and higher sensitivity to both calcium and heavy metal stress. Transformants constitutively expressing an active MoYPT7 allele (MoYPT7-CA, Gln67Leu) exhibited distinct phenotypes from the MoYPT7 mutant. Expression of MoYPT7-CA in MoYpt7 reduced pathogenicity and produced more appressoriaforming single-septum conidia. These results indicate that MoYPT7 is required for fungal morphogenesis, vacuole fusion, autophagy, stress resistance and pathogenicity in M. oryzae. [ABSTRACT FROM AUTHOR]

Inspiration for molecular design and construction can be derived from mathematically based structures. In the quest for new materials, the adaptation of new building blocks can lead to unexpected results. Towards these ends, the quantitative single-step self-assembly of a shape-persistent, Archimedean-based building block, which generates the largest molecular sphere (a cuboctahedron) that has been unequivocally characterized by synchrotron X-ray analysis, is described. The unique properties of this new construct give rise to a dilution-based transformation into two identical spheres (octahedra) each possessing one half of the molecular weight of the parent structure; concentration of this octahedron reconstitutes the original cuboctahedron. These chemical phenomena are reminiscent of biological fission and fusion processes. The large 6 nm cage structure was further analyzed by 1D and 2D NMR spectroscopy, mass spectrometry, and collision cross-section analysis. New routes to molecular encapsulation can be envisioned. [ABSTRACT FROM AUTHOR]

Inspiration for molecular design and construction can be derived from mathematically based structures. In the quest for new materials, the adaptation of new building blocks can lead to unexpected results. Towards these ends, the quantitative single-step self-assembly of a shape-persistent, Archimedean-based building block, which generates the largest molecular sphere (a cuboctahedron) that has been unequivocally characterized by synchrotron X-ray analysis, is described. The unique properties of this new construct give rise to a dilution-based transformation into two identical spheres (octahedra) each possessing one half of the molecular weight of the parent structure; concentration of this octahedron reconstitutes the original cuboctahedron. These chemical phenomena are reminiscent of biological fission and fusion processes. The large 6 nm cage structure was further analyzed by 1D and 2D NMR spectroscopy, mass spectrometry, and collision cross-section analysis. New routes to molecular encapsulation can be envisioned. [ABSTRACT FROM AUTHOR]

The perfect host: A discrete Ru6L4 capsule was synthesized as a solution counterpart of networked Co6L4 capsules, which can host various guests in the crystalline state using dynamic conformational changes. By harnessing the common dynamic nature of two hosts upon guest encapsulation, the solution host–guest chemistry of the Ru6L4 capsule was transferred into the crystalline state using networked Co6L4 capsules. [ABSTRACT FROM AUTHOR]

J. Neurochem. (2010) 113, 1436–1446. It is generally believed that temporary moderate stress to a living organism has protective and adaptive effects, but little is known about the responses of CNS to the moderate stresses at molecular level. This study aims to investigate the gene expression changes induced by moderate stress in CNS stress- and nociception-related regions of rats. Moderate restraint was applied to rats for 50 min and cDNA microarrays were used to detect the differential gene expression in different CNS regions. Transcriptome profiling analysis showed that at acute stage stress-related genes were up-regulated in arcuate nucleus; fight-or-flight behavior-related genes were up-regulated in periaqueductal gray, while nitric oxide and GABA signal transmission-related genes were up-regulated in spinal dorsal horn. In addition, immune-related genes were broadly regulated, especially at the late stage. These results suggested that specific genes of certain gene ontology categories were spatiotemporally regulated in specific CNS regions related to relevant functions under moderate external stimuli at acute stage, while immune response was broadly regulated at the late stage. The co-regulated genes among the three different CNS regions may play general roles in CNS when exposed to moderate stress. Furthermore, these results will help to elucidate the physiological processes involved in moderate stress in CNS. [ABSTRACT FROM AUTHOR]

Direct interference with the transforming potential of ErbB2 has become a subject of great interest. Disruption of critical ErbB2 ectodomain interactions may lead to novel therapeutic approaches for the treatment of various tumors. The ErbB receptor signaling can be inhibited by rationally designed peptide mimetics based on the subdomains of ErbB ectodomain. The mimetics can bind to the ErbB receptor specifically and block inter-receptor interactions, resulting in the growth inhibition of ErbB2-overexpressing cells in vitro. In this study, three-dimensional structure of herstatin, an autoinhibitor of ErbB2 and ErbB2 ectodomain complex was constructed by computer-aided molecular modeling. The binding site on ErbB2 ectodomain for herstatin was determined at S1 domain. The mutants of ErbB2 ectodomain were constructed. The interactions of ErbB2 ectodomain and its mutants with herstatin were analyzed for the first time in living cells that coexpressed herstatin and ErbB2 ectodomain or the mutants. The S1 domain in ErbB2 ectodomain was verified as the interaction site with herstatin by immunoprecipitation, confocal microscopy, and fluorescence resonance energy transfer (FRET). The binding region of herstatin on ErbB2 ectodomain might be a potential target region for the drug design. © 2005 Wiley-Liss, Inc. [ABSTRACT FROM AUTHOR]

Reactive acrylate esters were encapsulated in the cavity of networked molecular capsules in a single-crystal-to-single-crystal fashion. Owing to the encapsulation effect, acrylates inside the capsules do not undergo polymerization upon irradiation with UV light or heating, while the guest molecules can be quantitatively extracted by treatment with toluene. [ABSTRACT FROM AUTHOR]

Nanocapsules Host–guest chemistry in the crystalline state enabled the stable encapsulation of reactive acrylate esters into crystals of networked molecular capsules, as demonstrated by Guo ‐ Hong Ning, Yasuhide Inokuma, and Makoto Fujita in their Communication on page 466   ff. (see the Inside Cover). Since encapsulated acrylates can be extracted on demand, the networked molecular capsules can act as solid storage for industrially useful compounds. The authors report that crystals of networked molecular capsules accommodate several acrylate esters in a single ‐ crystal ‐ to ‐ single ‐ crystal fashion. The encapsulated acrylates do not undergo photo ‐ induced polymerization upon UV irradiation due to the encapsulation effect, while they can be released by treating the inclusion crystals with toluene. [ABSTRACT FROM AUTHOR]

In the crystal structure of the title compound, (C6H8N)[ZnCl4]·H2O, the Zn atom has a tetrahedral geometry and is coordinated by four Cl atoms. The water molecule and phenylammonium cations interact with two [ZnCl4]2− anions, forming discrete structural motifs via O—H...Cl and N—H...Cl/O interactions. Intermolecular π–π stacking is present between adjacent phenylammonium cations (centroid–centroid distance = 3.672 Å). [ABSTRACT FROM AUTHOR]

The crystal structure of the title compound, C14H17N3O5, is stabilized by inter­molecular O—H⋯N hydrogen bonds. [ABSTRACT FROM AUTHOR]

In the title compound, C4H12N+·C9H13NO3P−·CHCl3, there are two independent formula units in the asymmetric unit. In the crystal structure, intermolecular N—H...O hydrogen bonds form two independent one-dimensional chains along the a axis. [ABSTRACT FROM AUTHOR]