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BACKGROUND: To find more effective agricultural antibiotics, a class of new 2‐aminothiazole derivatives containing the 4‐aminoquinazoline moiety were synthesized and evaluated for their antimicrobial properties against phytopathogenic bacteria and fungi of agricultural importance. RESULTS: All the target compounds were fully characterized by 1H NMR, 13C NMR, and high‐resolution mass spectrometry. The bioassay results showed that compound F29 with a 2‐pyridinyl substituent exhibited an outstanding antibacterial effect against Xanthomonas oryzae pv. oryzicola (Xoc) in vitro, having an half‐maximal effective concentration (EC50) value as low as 2.0 μg/mL (over 30‐fold more effective than the commercialized agrobactericide bismerthiazol, with an EC50 value of 64.3 μg/mL). In addition, compound F8 with a 2‐fluorophenyl group demonstrated a good inhibitory activity toward the bacterium Xanthomonas axonopodis pv. citri (Xac), around twofold more active than bismerthiazol in terms of their EC50 values (22.8 versus 71.5 μg/mL). Interestingly, this compound also demonstrated a notable fungicidal effect against Phytophthora parasitica var. nicotianae, with an EC50 value largely comparable with that of the commercialized fungicide carbendazim. Finally, mechanistic studies revealed that compound F29 exerted its antibacterial effects by increasing the permeability of bacterial membranes, reducing the release of extracellular polysaccharides, and triggering morphological changes of bacterial cells. CONCLUSION: Compound F29 has promising potential as a lead compound for developing more efficient bactericides to fight against Xoc. © 2023 Society of Chemical Industry. [ABSTRACT FROM AUTHOR]

BACKGROUND: To discover more efficient antimicrobial agents in agriculture, a series of new quinazoline derivatives bearing both sulfonate ester and piperidine‐4‐carboxamide moieties were synthesized and assessed for their antimicrobial effects. RESULTS: All of the target compounds were fully characterized by proton (1H) nuclear magnetic resonance (NMR), carbon‐13 (13C) NMR, and high‐resolution mass spectroscopy (HRMS), and compound III‐6 containing a 3‐bromophenyl substituent was clearly confirmed via single‐crystal X‐ray diffraction analysis. The bioassay results indicated that some compounds displayed noticeable inhibitory effects in vitro against Xanthomonas oryzae pv. oryzicola (Xoc). Further measurements of median effective concentration (EC50) values showed that compound III‐17 bearing a 4‐methoxyphenyl group had the best anti‐Xoc efficacy (EC50 = 12.4 μg mL−1), far better than the commercialized bismerthiazol (77.5 μg mL−1). Moreover, this compound also demonstrated good protection and curative activities in vivo against rice bacterial leaf streak caused by Xoc. CONCLUSION: Compound III‐17 had a good potential for further development as a new bactericide for controlling Xoc. © 2023 Society of Chemical Industry. [ABSTRACT FROM AUTHOR]

Exploring new noncovalent bonding motifs with reversibly tunable binding affinity is of fundamental importance in manipulating the properties and functions of supramolecular self‐assembly systems and materials. Herein, for the first time, we demonstrate a unique visible‐light‐switchable telluro‐triazole/triazolium‐based chalcogen bonding (ChB) system in which the Te moieties are connected by azobenzene cores. The binding strengths between these azo‐derived ChB receptors and the halide anions (Cl−, Br−) could be reversibly regulated upon irradiation by visible light of different wavelengths. The cis‐bidentate ChB receptors exhibit enhanced halide anion binding ability compared to the trans‐monodentate receptors. In particular, the telluro‐triazolium‐based ChB receptor can achieve both high and significantly photoswitchable binding affinities for halide anions, which enable it to serve as an efficient photocontrolled organocatalyst for ChB‐assisted halide abstraction in a Friedel–Crafts alkylation benchmark reaction. [ABSTRACT FROM AUTHOR]

Controlling the phases of matter is a central task in condensed matter physics and materials science. In 2D magnets, manipulating spin orientation is of great significance in the context of the Mermin–Wagner theorem. Herein, a systematic study of temperature‐ and pressure‐dependent magnetic properties up to 1 GPa in van der Waals CrPS4 is reported. Owing to the temperature‐dependent change of the magnetic anisotropy energy, the material undergoes a first‐order spin reorientation transition with magnetic moments realigning from being almost parallel with the c axis in the ac plane to the quasi‐1D chains of CrS6 octahedra along the b axis upon heating. The spin reorientation temperature is suppressed after applying pressure, shifting the high‐temperature phase to lower temperatures with the emergence of spin‐flop transitions under magnetic fields applied along the b axis. The saturation field increases with pressure, indicating the enhancement of interlayer antiferromagnetic coupling. However, the Néel temperature is slightly reduced, which is ascribed to the suppression of intralayer ferromagnetic coupling. The work demonstrates the control of spin orientation and metamagnetic transitions in layered antiferromagnets, which may provide new perspectives for exploring 2D magnetism and related spintronic devices. [ABSTRACT FROM AUTHOR]

A photo‐switchable hetero‐complementary quadruple H‐bonding array, which consists of an azobenzene‐derived ureidopyrimidinone (UPy) module (Azo‐UPy) and a nonphotoactive diamidonaphthyridine (DAN) derivative (Napy‐1), is constructed based on a reversible photo‐locking approach. Upon UV (390 nm)/Vis (460 nm) light irradiations, photo‐switchable quadruple H‐bonded dimerization between Azo‐UPy and Napy‐1 can be achieved with exhibiting 4.8×104‐fold differences in binding strength (ON/OFF ratios). Furthermore, smart polymeric gels with unique photo‐controlled macroscopic self‐assembly behavior can be fabricated by introducing such quadruple H‐bonding array as photo‐regulable noncovalent interfacial connections. [ABSTRACT FROM AUTHOR]

Current plasmonic photocatalysts are mainly based on noble metal nanoparticles and rarely work in the infrared (IR) light range. Herein, cost‐effective Bi2O3−x with oxygen vacancies was formed in situ on commercial bismuth powder by calcination at 453.15 K in atmosphere. Interestingly, defects introduced into Bi2O3−x simultaneously induced a localized surface plasmon resonance (LSPR) in the wavelength range of 600–1400 nm and enhanced the adsorption for CO2 molecules, which enabled efficient photocatalysis of CO2‐to‐CO (ca. 100 % selectivity) even under low‐intensity near‐IR light irradiation. Significantly, the apparent quantum yield for CO evolution at 940 nm reached 0.113 %, which is approximately 4 times that found at 450 nm. We also showed that the unique LSPR allows for the realization of a nearly linear dependence of photocatalytic CO production rate on light intensity and operating temperature. Finally, based on an IR spectroscopy study, an oxygen‐vacancy induced Mars‐van Krevlen mechanism was proposed to understand the CO2 reduction reactions. [ABSTRACT FROM AUTHOR]

Current plasmonic photocatalysts are mainly based on noble metal nanoparticles and rarely work in the infrared (IR) light range. Herein, cost‐effective Bi2O3−x with oxygen vacancies was formed in situ on commercial bismuth powder by calcination at 453.15 K in atmosphere. Interestingly, defects introduced into Bi2O3−x simultaneously induced a localized surface plasmon resonance (LSPR) in the wavelength range of 600–1400 nm and enhanced the adsorption for CO2 molecules, which enabled efficient photocatalysis of CO2‐to‐CO (ca. 100 % selectivity) even under low‐intensity near‐IR light irradiation. Significantly, the apparent quantum yield for CO evolution at 940 nm reached 0.113 %, which is approximately 4 times that found at 450 nm. We also showed that the unique LSPR allows for the realization of a nearly linear dependence of photocatalytic CO production rate on light intensity and operating temperature. Finally, based on an IR spectroscopy study, an oxygen‐vacancy induced Mars‐van Krevlen mechanism was proposed to understand the CO2 reduction reactions. [ABSTRACT FROM AUTHOR]

Ionic liquids (ILs) have many attractive properties. For example, their physical and chemical properties can be tuned by a judicious design of the cations and anions, making them ideal candidates for designable building blocks of stimuli‐responsive materials. Numerous IL‐based stimuli‐responsive materials have been developed by chemical modification (covalent, coordination, or ionic functionalization) or physical blending of ILs with other functional materials. The flexible tunability of ILs provides a great opportunity to achieve the desired physicochemical properties for task‐specific applications, such as sensing, display, gas capture, and so on. This review aims to address the recent advances in IL‐based stimuli‐responsive materials, which are categorized by the type of external stimuli, including gas‐responsive, organic solvent‐responsive, ion‐responsive, pH‐responsive, thermo‐responsive, photo‐responsive, and electro‐responsive materials. [ABSTRACT FROM AUTHOR]

Iron oxide nanoparticles are nanomaterials that are used extensively in the biomedical field, but they are associated with adverse effects, including mitochondrial toxicity. Mitochondrial homeostasis is achieved through dynamic stability based on two sets of antagonistic balanced processes: mitochondrial biogenesis and degradation as well as mitochondrial fission and fusion. In this study, we showed that PEG‐COOH‐coated Fe3O4 (PEG‐Fe3O4) nanoparticles induced mitochondrial instability in dendritic cells (DCs) by impairing mitochondrial dynamics due to promotion of mitochondrial biogenesis through activation of the peroxisome proliferator‐activated receptor γ coactivator 1α (PGC1α) pathway, inhibiting mitochondrial degradation via decreased autophagy, and facilitating mitochondrial fragmentation involving increased levels of DRP1 and MFN2. The resulting reduced levels of dextran uptake, CD80, CD86 and chemokine receptor 7 (CCR7) suggested that PEG‐Fe3O4 nanoparticles impaired the functionally immature state of DCs. Autophagy inhibitor 3‐methyladenine (3‐MA) alleviated PEG‐Fe3O4 nanoparticle‐induced mitochondrial instability and impairment of the functionally immature state of DCs due to unexpected enhancement of PGC1α/MFN2‐mediated coordination of mitochondrial biogenesis and fusion. Iron oxide nanoparticles are adversely associated with mitochondrial toxicity. The present study showed that PEG‐COOH‐coated Fe3O4 (PEG‐Fe3O4) nanoparticles induced mitochondrial instability in dendritic cells (DCs) by promoting mitochondrial biogenesis, inhibiting mitochondrial degradation and facilitating mitochondrial fragmentation. The resulting reduced levels of dextran uptake, costimulatory molecules and chemokine receptor 7 suggested that PEG‐Fe3O4 nanoparticles impaired DC function. 3‐methyladenine alleviated PEG‐Fe3O4 nanoparticle‐induced mitochondrial instability and impairment of DC function due to enhancing the coordination of mitochondrial biogenesis and fusion. [ABSTRACT FROM AUTHOR]

Exploring dynamic bonds and their applications in fabricating dynamic materials has received great attention. A photoinduced [2]rotaxane‐based dynamic mechanical bond (DMB) features visible‐light‐triggered dynamic bonding behavior that is essentially distinguished from conventional dynamic chemical bonds. In this DMB, a photoisomerizable ortho‐fluoroazobenzene unit is introduced as a steric‐controllable stopper, the visible‐light‐induced dynamic wagging movement of which enables the photoregulated threading of the macrocycle. This allows reversible in situ de‐/reforming of the mechanical bond without involving dynamic chemical linkage. The DMB‐cross‐linked polymeric gel shows interesting photoinduced degradation behavior upon visible light irradiation. Benefiting from the distinctive dual dynamic nature of reversible bonding behavior and mechanical interlocked structure, this DMB is expected to serve as a new type of dynamic bond that can be applied in designing dynamic soft materials. [ABSTRACT FROM AUTHOR]

Abstract: The development of artificial self‐assembling systems with dynamic photo‐regulation features in aqueous solutions has drawn great attention owing to the potential applications in fabricating elaborate biological materials. Here we demonstrate the fabrication of water‐soluble cucurbit[8]uril (CB[8])‐mediated supramolecular polymers by connecting the fluorinated azobenzene (FAB) containing monomers through host‐enhanced heteroternary π–π stacking interactions. Benefiting from the unique visible‐light‐induced E→Z photoisomerization of the FAB photochromophores, the encapsulation behaviors between the CB[8] macrocycle and the monomers could be regulated upon visible light irradiation, resulting in the depolymerization of such CB[8]‐mediated supramolecular polymers. [ABSTRACT FROM AUTHOR]

Anionic polyacrylamide (PAM) can prevent soil erosion, but its effect on fine particulate phosphorus (P), such as colloidal P, has not been thoroughly examined. The effects of PAM on the release potentials of water-dispersible colloids (WDC) and total P, molybdenum-reactive P (MRP), and molybdenum-unreactive P (MUP) in the colloidal and truly dissolved phases (i.e., TPcoll, MRPcoll, MUPcoll, TPtruly, MRPtruly, and MUPtruly) from six soils across South China were tested in this study. The results showed that the release potentials of TPcoll in the control treatments were 6·9-46·1 mg kg−1 and generally highest in sandy loam soil. Following low (12·5 kg ha−1), middle (25 kg ha−1), and high (50 kg ha−1) levels of PAM application, the release potential of TPcoll decreased by 41·7, 63·2, and 77·4% compared to the control group, respectively. Additionally, PAM may trigger MRPcoll and TPtruly releases in sandy loam and/or silt soils, and for most soils, MRPtruly and MUPtruly showed the highest release potentials at middle or high PAM levels. A significant PAM application level by soil site interaction for the release potentials of WDC and colloidal P was observed. Multiple linear regression showed that the PAM rate combined with soil sand content can successfully predict the release potentials of WDC (R2 = 0·552, p < 0·001) and TPcoll (R2 = 0·738, p < 0·001). Our results suggest that PAM can effectively reduce the loss of soil colloids and colloidal P, while its effects are related to both application level and soil texture. Copyright © 2017 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

Isoniazid (INH) is a first-line antituberculosis drug that is adversely associated with hepatotoxicity. Recently, impairment of mitochondrial homeostasis involved in this side effect has been noticed. Mitochondrial homeostasis is achieved by the balance between the generation of functional mitochondria by biogenesis and elimination of dysfunctional mitochondria by autophagy. AMP-activated protein kinase (AMPK) can maintain mitochondrial stability through positive control of these two processes. In this study, we showed that AMPK activator acadesine (AICAR) alleviated INH-caused impairment of mitochondrial biogenesis by activation of silent information regulator two ortholog 1 (SIRT1)-peroxisome proliferator-activated receptor γ coactivator 1α (PGC1 α) pathway in HepG2 cells. However, mitochondrial instability and apoptosis were caused by AICAR along with an unexpected decrease in INH-induced cytoprotective autophagy. Therefore, AICAR failed to alleviate INH-caused mitochondrial instability in HepG2 cells due to its inhibitory effect on autophagy induced by INH. Copyright © 2017 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

Interlayer stacking of 2D covalent organic frameworks (COFs) plays a crucial role in determining not only the geometry of channels inside COFs but also the mobility of carrier transport between COF layers. However, though topological structures of 2D COFs monolayers can be precisely predicted through the structures of building blocks, factors affecting their interlayer stacking remain poorly understood. In this work, a truxene-based building block on which six methyl groups are introduced was designed. The condensation of it with 1,4-diaminobenzene or benzidine afforded 2D COFs with the methyl groups extending out-of-plane of the layers. A significant influence of the methyl groups on interlayer stacking of the COFs was revealed by the adoption of inclined packing of monolayers, which has never been experimentally observed before. This unprecedented stacking manner was confirmed by powder X-ray diffraction analysis, pore-size distribution analysis, and TEM investigation. [ABSTRACT FROM AUTHOR]

Integrating different kinds of pores into one covalent organic framework (COF) endows it with hierarchical porosity and thus generates a member of a new class of COFs, namely, heteropore COFs. Whereas the construction of COFs with homoporosity has already been well developed, the fabrication of heteropore COFs still faces great challenges. Although two strategies have recently been developed to successfully construct heteropore COFs from noncyclic building blocks, they suffer from the generation of COF isomers, which decreases the predictability and controllability of construction of this type of reticular materials. In this work, this drawback was overcome by a multiple-linking-site strategy that offers precision construction of heteropore COFs containing two kinds of hexagonal pores with different shapes and sizes. This strategy was developed by designing a building block in which double linking sites are introduced at each branch of a C3-symmetric skeleton, the most widely used scaffold to construct COFs with homogeneous porosity. This design provides a general way to precisely construct heteropore COFs without formation of isomers. Furthermore, the as-prepared heteropore COFs have hollow-spherical morphology, which has rarely been observed for COFs, and an uncommon staggered AB stacking was observed for the layers of the 2D heteropore COFs. [ABSTRACT FROM AUTHOR]

A hexaazatriphenylene (HAT) derivative (compound 1) that bears four n-octyl chains and two thienyl groups was designed and synthesized. Further light-induced oxidation coupling reaction led to thienyl-fused compound 2. Their photophysical and electrochemical properties and self-assembly behavior have been investigated by UV/Vis, fluorescence, and 1H NMR spectroscopies, cyclic voltammetry (CV), scanning electron microscopy (SEM), and powder X-ray diffraction (PXRD). Although the difference in compounds 1 and 2 only lie in one single bond that connects the two thienyl segments, they displayed remarkably different properties, revealing an interesting structure-property relationship. [ABSTRACT FROM AUTHOR]

Some individuals show severe cognitive impairment when sleep deprived, whereas others are able to maintain a high level of performance. Such differences are stable and trait-like, but it is not clear whether these findings generalize to physiologic responses to sleep loss. Here, we analyzed individual differences in behavioral and physiologic measures in healthy ethnic-Chinese male volunteers ( n = 12; aged 22-30 years) who were kept awake for at least 26 h in a controlled laboratory environment on two separate occasions. Every 2 h, sustained attention performance was assessed using a 10-min psychomotor vigilance task ( PVT), and sleepiness was estimated objectively by determining percentage eyelid closure over the pupil over time ( PERCLOS) and blink rate. Between-subject differences in heart rate and its variability, and electroencephalogram ( EEG) spectral power were also analyzed during each PVT. To assess stability of individual differences, intraclass correlation coefficients ( ICC) were determined using variance components analysis. Consistent with previous work, individual differences in PVT performance were reproducible across study visits, as were baseline sleep measures prior to sleep deprivation. In addition, stable individual differences were observed during sleep deprivation for PERCLOS, blink rate, heart rate and its variability, and EEG spectral power in the alpha frequency band, even after adjusting for baseline differences in these measures (range, ICC = 0.67-0.91). These findings establish that changes in ocular, ECG, and EEG signals are highly reproducible across a night of sleep deprivation, hence raising the possibility that, similar to behavioral measures, physiologic responses to sleep loss are trait-like. [ABSTRACT FROM AUTHOR]

Using GGA+ U approach based on the density functional theory, the on-site correlation and the electronic structure of wurtzite zinc oxide are investigated. By atomic population analysis, the zinc 3 d orbital is found to be almost fully filled, but the oxygen 2 p orbital is partially filled. So, the zinc oxide can be approximately regarded as a sort of d10 semiconductor. Similar to that of d0 magnets found previously, the on-site Coulomb repulsion of 2 p orbital in such a d10 system is shown to be also indispensable in addition to that of 3 d orbital. As the unconventional on-site Coulomb repulsion of O 2 p is considered, the theoretical results agree with the previous experimental observations satisfactorily. The partial density of states shows significant OZn hybridization in the valence band, but it decreases a little as the on-site correlations are taken into account. © 2013 Wiley Periodicals, Inc. [ABSTRACT FROM AUTHOR]

Chiral amplification is an interesting phenomenon in supramolecular chemistry mainly observed in complicated systems in which cooperative effect dominate. Herein, chiral, supramolecular, propeller-like architectures have been constructed through coassembly of an achiral disk-shaped molecule and chiral amino acid derivatives driven by intermolecular hydrogen bonding. Both the 'sergeants-and-soldiers' principle and 'majority-rules' effect are applicable in these discrete four-component supermolecules, which are the simplest supramolecular system ever reported that exhibit chiral amplification. [ABSTRACT FROM AUTHOR]

BACKGROUND During early embryonic development, maternal exposure to hyperthermia induces neural tube defects (NTDs). Connexins are essential for the formation of gap junctions and Connexin43 (Cx43) is crucially involved in neural tube development. This study was designed to explore the potential role of Cx43 in NTDs induced by hyperthermia. METHODS Using PCR, the Cx43 cDNA was screened from the cDNA library of the neural tube from golden hamsters treated with hyperthermia. By Northern blot, the expression of Cx43 in heat-treated and control groups of the golden hamsters at day 8.5 after mating was detected. Finally, by in situ hybridization and RT-PCR, the expression of Cx43 was examined in the neural tube at different time points after heat treatment. RESULTS Cx43 was stably expressed in heat-treated and control groups of the golden hamsters, whereas the expression was evidently higher in the heat-treated group. Cx43 expression in the neural tube at different time points after heat treatment was significantly higher than in control groups ( p < 0.01). Hyperthermia did not induce any mutations in Cx43 cDNA. CONCLUSIONS Our data provide the first evidence that hyperthermia induces upregulation of Cx43 in the golden hamster neural tube. NTDs caused by hyperthermia may be intimately related with the overexpression of Cx43. Birth Defects Research (Part A) 2012. © 2011 Wiley Periodicals, Inc. [ABSTRACT FROM AUTHOR]

Review: 39 refs. [ABSTRACT FROM AUTHOR]

Current plasmonic photocatalysts are mainly based on noble metal nanoparticles and rarely work in the infrared (IR) light range. Herein, cost‐effective Bi2O3−x with oxygen vacancies was formed in situ on commercial bismuth powder by calcination at 453.15 K in atmosphere. Interestingly, defects introduced into Bi2O3−x simultaneously induced a localized surface plasmon resonance (LSPR) in the wavelength range of 600–1400 nm and enhanced the adsorption for CO2 molecules, which enabled efficient photocatalysis of CO2‐to‐CO (ca. 100 % selectivity) even under low‐intensity near‐IR light irradiation. Significantly, the apparent quantum yield for CO evolution at 940 nm reached 0.113 %, which is approximately 4 times that found at 450 nm. We also showed that the unique LSPR allows for the realization of a nearly linear dependence of photocatalytic CO production rate on light intensity and operating temperature. Finally, based on an IR spectroscopy study, an oxygen‐vacancy induced Mars‐van Krevlen mechanism was proposed to understand the CO2 reduction reactions. [ABSTRACT FROM AUTHOR]

Current plasmonic photocatalysts are mainly based on noble metal nanoparticles and rarely work in the infrared (IR) light range. Herein, cost‐effective Bi2O3−x with oxygen vacancies was formed in situ on commercial bismuth powder by calcination at 453.15 K in atmosphere. Interestingly, defects introduced into Bi2O3−x simultaneously induced a localized surface plasmon resonance (LSPR) in the wavelength range of 600–1400 nm and enhanced the adsorption for CO2 molecules, which enabled efficient photocatalysis of CO2‐to‐CO (ca. 100 % selectivity) even under low‐intensity near‐IR light irradiation. Significantly, the apparent quantum yield for CO evolution at 940 nm reached 0.113 %, which is approximately 4 times that found at 450 nm. We also showed that the unique LSPR allows for the realization of a nearly linear dependence of photocatalytic CO production rate on light intensity and operating temperature. Finally, based on an IR spectroscopy study, an oxygen‐vacancy induced Mars‐van Krevlen mechanism was proposed to understand the CO2 reduction reactions. [ABSTRACT FROM AUTHOR]

In the title compound, [CoRu(C5H5)(C16H9)(C17H14P)2]PF6, the Ru(II) atom is coordinated by a cyclo-penta-dienyl ring in an η(5)-mode, one C atom from a 4,4'-diethynyl-1,1'-biphenyl ligand and two P atoms from a chelating 1,1'-bis-(di-phenyl-phosphan-yl)cobaltocenium ligand, giving a three-legged piano-stool geometry. In the crystal, weak C-H⋯F hydrogen bonds link the complex cations and hexa-fluorido-phosphate anions into a three-dimensional supra-molecular structure.