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A novel C–N bond activation strategy was established by developing new organic photoredox catalyst (Cz-NI-Ph), which provides a concise approach for the synthesis of amides from tertiary amines.

With lock–key interactions, colloidal antibiotic mimics can selectively capture the shape-matching microorganisms and photothermally kill them under NIR irradiation.

Reusable polystyrene-supported ionic liquid catalysts exhibit high catalytic activity for the synthesis of bisphenol compounds. The anions and cations of ionic liquids activate the substrates simultaneously, playing a synergistic catalytic role.

pH decrease changes the interbase hydrogen bonds and negative charge of the aptamer, destroying its affinity for Cd2+.

Poly(2,6-anthraquinonyl disulfide) with “S–S” connection unit provides a high Mg-storage capacity of 270 mA h g−1 with the extra capacity being delivered by formation of the SO/S–O bond between the enolized carbonyl (C–O−) and the S–S unit.

Polyanthraquinonylimides (PAQIs) are used as cathodes for rechargeable magnesium batteries. Large conjugated structure favors high capacity, stable cycling and good rate capability. PAQIs store Mg2+ and deliver a power density of 2780 W kg−1.

Synthesis of a specific As(iii)-ion-imprinted polymer for oxidation liquid phase color detection of As(iii) ions in aqueous system.

Herein, we report a cross-linking method for the assembly of coiled-coil peptides into long fibers under mild conditions.

This study exhibits potential prospects in thermal management fields and promising alternatives for the thermal harvesting of renewable energy.

An inverse-electron-demand oxa-Diels-Alder reaction of 5-alkenyl thiazolones with β,γ-unsaturated carbonyl compounds enabled by quinine thiourea was studied, which allows the enantioselective synthesis of a broad range of highly functionalized pyranthiazoles bearing three continuous stereocenters. This protocol is adaptable to a wide scope of substrates and has great potential for scale-up synthesis and facile transformation.

A protocol for the chemically divergent synthesis of β-lactams and α-amino acid derivatives with isothiourea (ITU) catalysis by switching solvents was developed. The stereospecific Mannich reaction occurring between imine and C(1)-ammonium enolate generated zwitterionic intermediates, which underwent intramolecular lactamization and afforded β-lactam derivatives when DCM and CH

Large-scale CNT films are prepared by a continuous method and used to fabricate a flexible high-capacity and long-cycling anode for sodium-ion batteries by in-situ growth of NiCo2S4 nanosheets anchored on the CNTs.

Vitamins may play an important role in preventing tuberculosis. The purpose of this work is to associate the vitamin A, C, D and E status with tuberculosis through a systematic review and meta-analysis of observational studies. Web of Science, Pubmed and Scopus were searched from the earliest date of the database to May 2021. The standardized mean differences (SMDs) of blood vitamin concentrations and odds ratios (ORs) of vitamin deficiency between the tuberculosis patients and the control subjects were used as the main effect sizes. The effect sizes were pooled by a random-effects model using the Stata software (Version 11). The vitamin A concentration was significantly lower in the tuberculosis group than in the control group [SMD (95% CI): -0.96 (-1.31, -0.61)

A metal-free amino-heteroarylation of unactivated olefins via new organic photoredox catalysis was reported, providing a concise and efficient approach for the rapid synthesis of various δ (β, ε)-amino ketones under mild conditions. A series of mechanistic experiments and DFT calculations indicate that this transformation undergoes a photoredox catalytic sequential radical addition/functional group migration process.

Organophotoredox catalytic four-component radical-polar crossover cascade reactions for the stereoselective synthesis of β-amido sulfones with high atom-, step-, and redox economy and excellent diastereoselectivity.

We have developed a metal-free, visible-light driven chiral phosphoric acid catalyzed asymmetric intermolecular, three-component radical-initiated dicarbofunctionalization and oxytrifluoromethylation of enamines.

14d-ECM secreted by BMSCs promotes the osteogenic differentiation of BMSCs. The underlying mechanism may be related to COL4A2 in 14d-ECM via activation of the FAK/PI3K/AKT signaling pathway.

ARosa roxburghiiTratt fruit polysaccharide was used to protect the colonic barrier function.

A strategy for the dehydrogenative amination of alkenes has been developed without using any oxidants and noble metals and with H2 released as the only by-product.

Propionamide (PA), an important pollutant emitted into the atmosphere from a variety of sources, is abundant in many areas worldwide, and could be involved in new particle formation (NPF). In this study, the enhancement of the H2SO4 (SA)-based NPF by PA was evaluated through investigating the formation mechanism of (PA)m(SA)n (m = 0–3 and n = 0–3) clusters using computational chemistry and kinetics modeling. Our study proved that the formation of all the PA-containing clusters is thermodynamically favorable. Furthermore, the O group in PA plays an important role in the clusters with more PA than SA, and the basicity of bases exerts a greater influence with an increasing amount of SA. We demonstrate that although the enhancing potential of PA is lower than that of the strongest enhancers of SA-based NPF such as methylamine (MA) and dimethylamine (DMA), PA can enhance the SA-based NPF at the parts per billion (ppb) level, which is typical for concentrations of C3-amides in, for example, urban Shanghai (China). The monomer evaporation is the dominant degradation pathway for the (PA)m(SA)n clusters, which differs from that of the SA–DMA system. The formation rate of PA-containing clusters is comparable to the rate coefficients for PA oxidation by hydroxyl (OH) radicals, indicating that participating in the SA-based NPF is a crucial sink for PA.

The optimizing method of electrolyte formulation is always vital for the development of high-performance lithium-ion batteries. Traditional optimization methods are mainly aimed at the optimization of the electrolyte composition type, and less attention is paid to the optimization of the composition proportion in a certain electrolyte formulation. In this paper, in order to balance the relationship between aluminum (Al) foil corrosion inhibition and battery electrochemical performance, the electrolyte system LiFSI0.6–LiBOB0.4–EC/DEC/EMC (1 : 1 : 1, by volume) was optimized by combining the simplex method, normalization and electrochemical testing. A lithium iron phosphate (LiFePO4) cathode with the optimized electrolyte of LiFSI0.53–LiBOB0.35–EC/DEC/EMC (1.3 : 1.5 : 1.5) delivers a high capacity (143.1 mA h g−1 at 0.5C) and remarkable cycle life (94.9% retention after 100 cycles) at 45 °C. The outstanding performance is attributed to the composition of the cathode electrolyte interphase (CEI) containing the solid and dense LiF, AlF3, B2O3 and Li2CO3. This provides a new method and idea for future electrolyte formulation optimization.

Hybrid photochromic materias (HPMs), especially crystalline HPMs (CHPMs), have been widely investigated due to their feasibility in maintaining the advantages of each constituent and genearating captivating photomodulated functionality. Metal-organic complexes (MOCs), as promising candidates for fabricating CHPMs, have attracted the interest of researchers. The molecular predesign of ligands plays a crucial role in yielding MOC-based CHPMs with tunable photochromic functionality. Hitherto, a great majority of CHPMs are driven by photosensitive ligands. However, the complicated synthesis and high cost of photosensitive ligands obviously prevent the macro-synthesis and future application of these CHPMs. Thus, it is indispensable to explore novel branches of CHPMs. Herein, we report a series of photochromic solid materials bearing modulated photochromic properties by hybridizing metal chlorides with a nonphotosensitive coplanar dipyridine unit 1,10-phenanthroline (phen) and its derivative 5-chloro-1,10-phenanthroline (5-Cl-phen). The resulting hybrids, [ZnCl2(phen)] (1), [CdCl2(phen)] (2), [PbCl2(phen)] (3), [ZnCl(H2O)(5-Cl-phen)2]Cl·2H2O (4), [Cd2Cl4(5-Cl-phen)2] (5) and [Pb2Cl4(5-Cl-phen)2] (6), exhibit distinct structures from the isolated molecular complexes (1 and 4) to the hybrid chain (2, 3, 5 and 6) because of the distinct coordination mode of central metal ions and chloride ions. After photo-irradiation with a Xe-lamp, all complexes, as expected, exhibited apparent color change because of the photoinduced electron transfer (ET) between coordinated chloride ions (Cl-) as electron donors (EDs) and the coordinated coplanar phen and 5-Cl-phen species as electron acceptors (EAs). More importantly, the photochromic performance of the title complexes could be modulated by phen and 5-Cl-phen. This study provides a general and facile way for modulating the structure and photochromic performance of hybrid metal chlorides with phen or phen-based derivatives under the synergy of crystalline engineering strategy and ET mechanism.

A green and practical divergent Ritter-type amination via a photoredox catalytic four-component radical-polar crossover process was developed. This versatile protocol presents a modular and powerful strategy to access functionalized β-sulfonyl imides and imines under mild conditions from readily available and stable substrates with high atom-, step- and redox economy. We manipulated carboxylic acids and benzotriazoles to precisely attack the nitrilium ion instead of the carbocation, thus preventing many complicated side reactions of the photocatalytic reactions. Furthermore, the synthetic utility of this divergent Ritter reaction is further demonstrated by the late-stage modification of pharmaceutical and natural product derivatives.

Sulfhydryl compounds are regarded as potential functional monomers for arsenious acid imprinted polymers due to their high affinity to arsenious acid in aqueous solution. However, the recognition and binding mechanisms between arsenious acid and sulfhydryl compounds in solutions remain unclear. In this work, the binding interactions between arsenious acid and dithiothreitol (DTT)/dithioerythritol (DTE) in aqueous solution and HEPES buffer at different pH values were investigated using density functional theory (DFT) calculations. DTE binding complexes were calculated to be more energetically favorable than DTT. H3AsO3–DTE−–H2O and H3AsO3–DTE–HEPES− complexes were shown to have the greatest affinity with the occurrence of deprotonation as pH changes. This indicates that the optimal pH ranges of binding between the template and monomer (DTT/DTE) in aqueous solution and HEPES buffer are 8.30–9.23 and 7.50–8.30, respectively. The reduced density gradient (RDG) method and non-covalent interaction (NCI) analysis demonstrated the presence of hydrogen bonds, van der Waals forces and repulsive forces in the systems. Energy decomposition analysis (EDA) predicted that the electrostatic force is the dominant composition of binding energy. The non-covalent properties of hydrogen bonds were further explained by the quantum theory of atoms in molecules (QTAIM) analysis. The calculated infrared (IR) spectrum reflected the formation of hydrogen bonds, which agreed well with the experimental IR spectrum. The change rate of the absorbance in ultraviolet-visible spectroscopy (UV-Vis) provided information for the best binding of H3AsO3–DTE in HEPES solution.

Polychlorinated dibenzo-p-dioxins/dibenzofurans (PCDD/Fs) and polychlorinated dibenzothiophenes/thianthrenes (PCDT/TAs) are two groups of dioxin-like compounds with oxygen and sulfur substitution, respectively. Chlorophenols (CPs) and chlorothiophenols (CTPs) are direct precursors in PCDD/F and PCDT/TA formation. The formation of chlorophenoxy radicals (CPRs) and chlorothiophenoxy radicals (CTPRs) from chlorophenols (CPs) and chlorothiophenols (CTPs) with O(3P) is an important initial step for the formation of PCDD/Fs and PCDT/TAs, respectively. In this paper, the formation of CPRs/CTPRs from the complete series reactions of 19 CP/CTP congeners with O(3P) was studied using the density functional theory (DFT) method. The rate constants of each reaction were calculated using canonical variational transition state (CVT) theory along with a small-curvature tunneling (SCT) contribution over a wide temperature range of 600–1200 K. The effect of the chlorine substitution pattern on the structural parameters, thermochemical properties and rate constants in both CPs and CTPs was discussed. This study shows that the reactions between CPs and O(3P) can be affected by the chlorine substitution at the para-position, and the reactions between CTPs and O(3P) are mostly influenced by both ortho-substitutions. The thiophenoxyl-hydrogen abstraction from CTPs by O(3P) is more likely to occur than the phenoxyl-hydrogen abstraction from CPs by O(3P). Comparison of the reactivity of CP/CTPs with O(3P) with our previous work on CP/CTPs with H and OH shows that the order for phenoxyl-hydrogen abstraction potential is CP + OH > CP + O(3P) > CP + H, and the order for thiophenoxyl-hydrogen abstraction potential is CTP + O(3P) > CTP + H > CTP + OH.

Rechargeable Mg-Li hybrid batteries have the merits of a Mg metal anode and a Li+ intercalation cathode, but the limited availability of Li resources hinders their large-scale application. Herein, rechargeable Mg-Na and Mg-K hybrid batteries are constructed with a low-defect Co3[Co(CN)6]2 nanocube cathode. The large redox active cavities of Co3[Co(CN)6]2 are highly favorable for reversible Na+ and K+ intercalations. The Mg-Na and Mg-K hybrid batteries provide reversible capacities of 123 and 126 mA h g-1, respectively, and a stable long-term cycling over 600 cycles. By contrast, the Mg-Li hybrid battery delivers a much lower capacity of 55 mA h g-1. It is also demonstrated that controlled crystallization of well-defined nanocubes with few lattice defects is important for these high-capacity Mg-Na and Mg-K hybrid battery cathodes. The low-defect Co3[Co(CN)6]2 nanocube cathode shows good rate capability, providing specific capacities of 45 and 53 mA h g-1 at 1000 mA g-1 in Mg-Na and Mg-K hybrid batteries, respectively. This study illustrates that low-defect Prussian blue analogs of Co3[Co(CN)6]2 are highly compatible and promising cathodes for Mg-Na and Mg-K hybrid batteries. The present study also provides a new method for the development of low-cost and high-performance batteries based on Mg metal anodes.

A Sc(OTf)3 catalyzed [3 + 2]-annulation reaction between donor–acceptor aziridines and several exo-glycals has been developed. Using this method, some exo-glycals derived from D-ribose, D-galactose and uridine can be converted into carbohydrate-spiro-heterocycles easily in good yields. Simple derivatization of the products gives proline analogues and polycyclic compounds. Moreover, this reaction disclosed the stereochemistry characteristic of the reaction between racemic D–A aziridines and chiral enolethers.

An efficient copper-catalyzed radical ring-opening halogenation with HX (aq) is described. This protocol features redox-neutral conditions, green halogen sources, and a broad substrate scope, providing practical access to distally chlorinated, brominated and iodinated alkyl ketones and alkyl nitriles with moderate to good yields.

A metal-free C(sp3)-H phosphorylation of saturated aza-heterocycles via the merger of organic photoredox and Bronsted acid catalyses was established under mild conditions. This protocol provided straightforward and economic access to a variety of valuable α-phosphoryl cyclic amines by using commercially available diarylphosphine oxide reagents. In addition, the D-A fluorescent molecule DCQ was used for the first time as a photocatalyst and exhibited an excellent photoredox catalytic efficiency in this transformation. A series of mechanistic experiments and DFT calculations demonstrated that this transformation underwent a sequential visible light photoredox catalytic oxidation/nucleophilic addition process.

Edible vegetable oils are easily contaminated by heavy metals, resulting in the oxidative degradation of oils and various health effects on humans. Therefore, it is very important to develop a rapid and efficient method to extract trace heavy metals from vegetable oils. In this work, a highly hydrophobic ion-imprinted polymer (IIP) was synthesized on a novel raspberry (RS)-like particle surface. The synthesized IIP@RS was characterized and used in solid-phase extraction (SPE) for the selective and fast adsorption of Cd(ii) from vegetable oils. The results showed that IIP was successfully coated onto RS particles with a high specific surface area (458.7 m

An aliovalent mixed-metal framework DUT-174 [LiAl(2-methylimidazolate)4]n, isostructural to ZIF-8, was synthesized from lithium aluminum hydride (LiAlH4) and 2-methylimidazole (2-mImH) through dehydrogenation. Lithium and aluminum cations acting as alternating framework nodes are coordinated tetrahedrally by (2-mIm)-. DUT-174 has a high specific surface area of 1149 m2 g-1 and CO2 uptake of 11.57 mmol g-1 at 195 K.

Studies on transuranic oxides provide a particularly valuable insight into chemical bonding in actinide compounds, in which subtle differences between metal ions and oxygen atoms are of fundamental importance for the stability of these compounds as well as their existence. In the case of neptunium, it is still mainly limited to specific Np oxide compounds without periodicity in the formation of stable structures or different oxidation states. Here, we report a systematic global minimum search of Np2Ox (x = 1–7) clusters and the computational study of their electronic structures and chemical bonding. These studies suggest that Np(V) ion could play the structure-directing role, and thus the mixed-valent Np(III/V) in Np2O4 is predicted accessible. In comparison with lower oxidation state Np analogues, significant 5f-orbital covalent interactions with Np(V)O bonding are observed, which shows that these model neptunium oxides can provide new understandings into the behavior of 5f-electrons in chemical bonding and structural design.

In vitro transcription is a convenient platform for fabricating nanodevices and has been used for assembling synthetic networks. However, it remains challenging to regulate synthetic cell-free in vitro transcription by multiple stimuli in a simple and programmable way. We proposed a strategy to regulate in vitro transcription by controlling the transcription templates' promoter domain via variable DNA inputs. To demonstrate the utility of this strategy, various logic circuits and cascading circuits were implemented. With the advantage of simplicity, modularity, programmability, and extensibility, the proposed strategy has potential in biocomputing, bioanalytical, and therapeutic applications.

The combination of a conjugated coplanar dipyridine moiety 1,10-phenanthroline (1,10-phen) with a metal carboxylate system produces two isostructural supramolecular chains [M(HBTA)(1,10-phen)2] (M = Zn for 1, M = Cd for 2) (H3BTA = benzene-1,2,3-tricarboxylic acid). Both 1 and 2 feature monomeric units as molecular building blocks (MBBs), which further connect with each other to form a supramolecular chain via forming hydrogen bonds with adjacent units. The coordinate linkage of 1,10-phen as π-electron acceptors (π-EAs) and tricarboxylate as electron donors (EDs) results in the electron transfer (ET)-induced photochromic functionality of 1 and 2 in response to Xe-lamp irradiation under ambient conditions. Distinct from the plenty of previous photochromic compounds derived from photosensitive moieties such as pyridinium-derivatives and photodeformable molecules, the photochromism in 1 and 2 is driven by the photoinduced ET between tricarboxylate and non-photochromic 1,10-phen units. Because of the coplanar characteristics of 1,10-phen, the photoactivated samples feature good stability under ambient conditions. More importantly, the resulting photochromism of isostructural 1 and 2 could be modulated by the category of metal ions, which is totally different from the previous works with focus on the design of organic ligands. Considering the great varieties of carboxylate ligands, this work offers a general method for the construction of photochromic complexes via integrating coplanar 1,10-phen units with metal-carboxylate systems under the guidance of the ET mechanism and MBB assembly strategy and modulating the photochromism of the resultant isostructural products via tuning the category of metal ions.

Polychlorinated phenoxathiins (PCPTs) are one group of dioxin-like compounds, which can be considered to be one-oxygen-substituted polychlorinated thianthrene (PCTA) compounds or one-sulfur-substituted polychlorinated dibenzo-p-dioxin (PCDD) compounds. Owing to their high toxicity and wide distribution, clarifying the formation and emission of PCPTs due to combustion and thermal processes can deepen our understanding of the dioxin formation mechanism and allow reduced-emission and dioxin-control strategies to be established. Chlorophenols (CPs) and chlorothiophenols (CTPs) are direct precursors in PCPT formation. In this paper, the homogeneous gas-phase formation mechanisms of PCPTs, as well as polychlorinated dibenzofurans (PCDFs) and polychlorinated dibenzothiophenes (PCDTs), from the cross-condensation of 2-chlorophenoxy radicals (2-CPRs) and 2-chlorothiophenoxy radicals (2-CTPRs) under thermal and combustion conditions were investigated theoretically using a density functional theory (DFT) method. The reaction priorities and effects of water molecules on the formation mechanisms were discussed. The rate constants of crucial elementary steps were calculated from 600–1200 K. The acute and chronic toxicities of the main products were predicted at three trophic levels. This study shows that routes starting with oxygen–carbon condensation are favored over those starting with sulfur–carbon condensation for PCPT formation, and routes ending with Cl loss can occur more easily than those ending with H loss. Water molecules have a negative catalytic effect on CH–S H-transfer steps but a positive catalytic effect on CH–O H-transfer steps.

In this study, an efficient catalytic system composed of deep eutectic solvents (DESs) was developed by adjusting the basicity of hydrogen bond donors (HBDs) to synthesize poly(isosorbide) carbonate (PIC) with high weight average molecular weight (Mw). It was demonstrated that the Mw of PIC prepared by using nearly neutral [EminOH]Cl–2EG was the highest. The results of the transesterification kinetics with different catalysts supported that the transesterification rate was significantly promoted as the basicity of DESs increased but their strong alkalinity inhibited the Mw of PIC. Therefore, the degradation of PIC was investigated to reveal the mechanism of the influence of basicity on the molecular weight of PIC. The strong alkalinity of DESs would cause the depolymerization of the macromolecular chains and ultimately limit the molecular weight of the product, proving the experimental fact that a near-neutral catalyst was more conducive to the Mw of PIC. Finally, a reasonable mechanism of synergistic catalysis was proposed based on 1H NMR spectroscopy, Fourier transform infrared spectroscopy (FT-IR) and experimental results. The metal-free, low-cost, high catalytic activity DES catalyst involved here is a practical candidate for advanced bio-based polycarbonate.

We report controllable assembly of polystyrene (PS) microspheres via a photocatalytically driven electroosmotic flow deriving from UV irradiation of Ag3PO4 nanoparticles in water. A series of assembly phases, including crystallites, chains and gels, are programmed by systematically modulating the UV intensity, the packing density of the PS microspheres and the concentration of the Ag3PO4 nanoparticles. Our findings demonstrate an important ability of light-responsive nanoparticles for colloidal assembly, which offers a new pathway toward effective manipulation of assembly at the microscale.

In recent years, synthetic apatite-doped rare-earth luminescent materials and their optical properties have attracted extensive worldwide attention. In this study, a series of novel green phosphors Sr2Y3(SiO4)2(PO4)O:Eu2+ with apatite structure was fabricated via a high temperature solid-state reaction. X-ray diffraction, structure refinement, photoluminescence excitation, emission spectra, and temperature-dependent emission intensity were employed to describe the phase and property of the samples. Under the excitation of 365 nm, the phosphors emit strong green emission in the broad band range from 400 nm to 700 nm, which almost covers the visible light spectrum. The quenching concentration of Eu2+ in Sr2Y3(SiO4)2(PO4)O was about 0.05, which was attributed to the dipole–dipole interactions. The evidence that the as-prepared phosphor can be successfully excited by near ultraviolet light indicates that it can be potentially used as a near UV-convertible phosphor for white light-emitting diodes.

The synthesis of high-molecular-weight bioderived polycarbonates via green routes and regulation of molecular weight is of great significance and is highly challenging. Herein, a green sequential approach toward the synthesis of bio-derived polycarbonates with adjustable molecular weights from isosorbide and dimethyl carbonate (DMC) has been developed by employing ionic liquids (ILs) as a class of eco-friendly catalysts. The structures of IL catalysts can be designed readily to control the molecular weight of isosorbide-derived polycarbonates (PIC), which is an attractive advantage of IL catalysts instead of the conventional metal-containing catalysts. In the presence of the [Bmim][4-I-Phen] catalyst, the PIC weight-average molecular weight (Mw) can reach 50 300 g mol−1. By the combination of the experimental results and DFT calculations, an IL anion–cation synergistic catalytic polymerization mechanism has been proposed, which reveals the nucleophile–electrophile dual activation by H-bonds and charge–charge interactions in catalyzing the formation of PIC. The significance of this study is that it provides guidance for developing IL catalysts for synthesizing higher molecular weight polycarbonates, thereby conveniently leading to a variety of polymers with tunable properties.

Two-dimensional carbon-based composite nanosheets (2D-CCNSs) are expected to be promising electrodes for fast charging lithium-ion batteries. Even though synthesis procedures exist for these materials, current approaches often require rigid reaction conditions and complicated synthetic steps. Herein, we develop a facile and general approach to fabricate a new type of 2D-CCNSs and demonstrate its superiority as a high-rate anode for lithium-ion batteries. It is found that the introduction of a nanocellulose as building unit can guide itself to self-assemble with polydopamine and metal ions to form a 2D inorganic–organic hybrid, which can be directly transformed into 2D-CCNSs after a carbonization treatment without structural deterioration. Unlike common 2D-CCNSs with a pure graphitic or amorphous carbon framework, the as-constructed materials possess a distinctively heterogeneous carbonaceous skeleton comprising graphitic nanorods with a crystalline framework and amorphous carbon with a microporous structure. The synthetic strategy is also demonstrated to be general for embedding numerous metal oxides, such as Fe2O3, CoO, NiO nanoparticles, into the carbon framework just by adjusting the types of metal ions. Profiting from the well-orchestrated structure, the as-prepared 2D-CCNSs exhibit impressive high-rate lithium ion storage performance. For instance, after being fully charged within 40.8 s, a long discharge time as high as 342 min can be achieved accompanied with a high and stable reversible capacity of 560 mA h g−1.

Nonribosomal peptides (NRPs) that are synthesized by modular megaenzymes known as nonribosomal peptide synthetases (NRPSs) are a rich source for drug discovery. By targeting an unusual NRPS architecture, we discovered an unusual biosynthetic gene cluster (bsm) from Streptomyces sp. 120454 and identified that it was responsible for the biosynthesis of a series of novel linear peptides, bosamycins. The bsm gene cluster contains a unique monomodular NRPS, BsmF, that contains a cytochrome P450 domain at the N-terminal. BsmF (P450 + A + T) can selectively activate tyrosine with its adenylation (A) domain, load it onto the thiolation (T) domain, and then hydroxylate tyrosine to form 5-OH tyrosine with the P450 domain. We demonstrated a NRPS assembly line for the formation of bosamycins by genetic and biochemical analysis and heterologous expression. Our work reveals a genome mining strategy targeting a unique NRPS domain for the discovery of novel NRPs.

Grafting conjugated dipyridine derivatives, BPB (1,4-bis(pyrid-4-yl)benzene) and BPBP (4,4'-di(pyridin-4-yl)-1,1'-biphenyl), to a metal phosphite system yields two hybrid zincophosphites [Zn2(HPO3)2(BPB)]·0.5DMF (1, DMF = N,N-dimethylformamide) and [H2BPBP]3·[Zn5Cl8(HPO3)4]·2H2O (2). 1 shows a hybrid layer with the inorganic zincophosphite chains as building blocks. 2 shows isolated pentanuclear Zn clusters in which four phosphite moieties as a bridging ligand, together with eight chloride ions as terminal ligands, bond with five Zn ions to produce anionic inorganic clusters. The negative charge was compensated by the protonated dipyridine derivative species, which was located in the intercluster voids and interplays with the adjacent clusters via N-HO-P hydrogen bonds. Interestingly, 1 and 2 show photochromism driven by the coordinate bond- and hydrogen bond-assisted electron transfer (ET) under the stimulus of Xe lamp irradiation in ambient conditions. Although 1 and 2 had similar constituents in terms of electron donors (EDs) and electron acceptors (EAs), they exhibited distinct photochromic mechanism with ligand-to-ligand ET (LLET) for 1 and proton-coupled ET (PCET) for 2. Unlike the majority of previous hybrid photochromic materials supported by photo-responsive species, the photochromism in 1 and 2 was based on the ET between phosphite and non-photochromic dipyridine derivative units. Our work provides a general strategy towards the design of photochromic hybrid phosphites by integrating conjugated dipyridine- or polypyridine derivative units with metal phosphites.

Studies have shown that the simultaneous regulation of tumor cell proliferation and the suppressive tumor immune microenvironment (TIME) could achieve better therapeutic effects. However, the targets of the proliferation and the TIME are different, which greatly limits the development of cancer therapy. A recent study found CD155, a highly expressed poliovirus receptor in melanoma cells and melanoma-infiltrating macrophages, functions as both an oncogene and immune checkpoint. Thus, it is supposed that targeting CD155 could bring dual therapeutic effects. Herein, we propose silencing the CD155 of melanoma cells and melanoma-infiltrating macrophages by a nanoparticle-delivered small interference RNA (siRNA) targeting CD155 (siCD155). We encapsulated siCD155 into cationic lipid-assisted nanoparticles (CLANsiCD155) and demonstrated that the intravenous injection of CLANsiCD155 could efficiently deliver siCD155 into melanoma cells and melanoma-infiltrating macrophages. The downregulation of CD155 in melanoma cells directly inhibited their proliferation, and meanwhile, the downregulation of CD155 in melanoma-infiltrating macrophages increased the activation of NK cells and T cells. Owing to this dual effect, CLANsiCD155 significantly inhibited the growth of B16-F10 melanoma. Our study suggests that nanoparticle-delivered siCD155 may be a simple but effective strategy for inhibiting tumor proliferation and reprogramming TIME.

It is an immense challenge to design catalysts for synthesizing high molecular weight polycarbonates using CO2, CO2-based compounds, or biorenewable chemicals as building blocks. To this end, an eco-compatible approach to synthesizing polycarbonates from biorenewable isosorbide and CO2-derived dimethyl carbonate (DMC) has been exploited: the regulation of poly(isosorbide carbonate) molecular weight can be achieved by modifying the cation structure of ionic liquid (IL) catalysts. The hydrogen bond donating and accepting ability of ILs can be altered by adjusting the cation structure, which successfully leads to the tunability of the intrinsic imbalance reactivity of exo-OH and endo-OH in isosorbide. Moreover, these ILs exclusively activate the carbonyl carbon of DMC for accelerating the polymerization reaction. These features are appealing superiorities of ILs as compared to catalysts involving metallic elements. The [Emim]Br catalyst remarkably decreased the imbalanced reactivity of –OH groups of isosorbide, and exhibited the highest catalytic activity. With the presence of [Emim]Br, the poly(isosorbide carbonate) (PIC) weight-average molecular weight and glass transition temperature attained were 52 100 g mol−1 and 156 °C, respectively. Additionally, according to experimental results, DFT calculations, and in situ1H NMR analysis, a possible polymerization mechanism indicates that bromine-derived ILs participate in nucleophilic–electrophilic dual-activation in catalyzing PIC synthesis. Our work offers a direction to design catalysts for synthesizing PICs with higher molecular weights through an eco-compatible route.

BiVO4 nanoparticles with tailored sizes and rich oxygen vacancies were facilely synthesized via pulsed laser irradiation of colloidal nanoparticles (PLICN). As anode materials for Na-ion batteries, the revolutionized sodium storage process found in sub-10 nm BiVO4 nanocrystals results in outstanding properties including extraordinary rate capability and remarkable cycling stability.

Rechargeable Mg batteries are considered as low-cost and reliable candidates for efficient energy storage, but their development is blocked by the lack of suitable cathode materials. In this work, Sb2Se3 nanowires and Bi2Se3 nanosheets are fabricated by facile one-step hydrothermal methods and their Mg-storage performances are systematically investigated. The results show that the Bi2Se3 nanosheets with stable hierarchical 2D structure exhibit a better performance. Because of its thin nanosheet structure, Bi2Se3 provides a high Mg-storage capacity of 144 mA h g-1 and a remarkable rate capability with 65 mA h g-1 delivered at 1000 mA g-1. Bi2Se3 also exhibits an outstanding cyclability over 350 cycles owing to its hierarchical structure. Furthermore, this study reveals that the electrochemical charge/discharge cycling is a typical conversion reaction occurring between Bi3+ and metallic Bi0. Kinetic investigation suggests that the high performance of Bi2Se3 is attributed to both its intrinsic nature and its thin nanosheet structure facilitating solid-state Mg2+ diffusion. The present work highlights the selection principle of conversion cathodes for rechargeable Mg batteries, namely matching a soft anion with a quasi-soft metal cation. Moreover, the facile synthesis approach is also used for low-dimensional main-group VI metal chalcogenides to improve the Mg-storage performance.