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Indium can efficiently mediate the Reformatsky reaction of iododifluoroacetylketones with aldehydes to afford the corresponding α,α-difluoro-β-hydroxyketones in high yield in pure water This reaction has excellent substrate suitability and functional group selectivity and provides an efficient approach for the synthesis of bioactive molecules containing the α,α-difluoro-β-hydroxyketone pharmacophore.

The pumpkin has been used frequently as functional foods. Phytochemical and pharmacological investigations have shown that polysaccharides derived from pumpkins, have antioxidant, anti-tumor, immun...

The root of Angelica sinensis (Oliv.) Diels, a well-known Chinese herbal medicine, has been used historically as hematopoietic and anti-inflammatory agents for thousands of years. Recent phytochemistry and pharmacological studies have proved that polysaccharides are one of the major active ingredients in A. sinensis. It has been demonstrated that ASPs (A. sinensis polysaccharides) had various important biological activities, such as hematopoietic, hepatoprotective, hypoglycemic, anti-inflammatory, antitumor, and antioxidant activities. The purpose of this present review is to appraise previous and current literatures on the extraction, purification, structural characterization and biological activities of ASPs. In addition, the structure–activity relationship will be further explored and discussed. We believe that this review will provide a useful bibliography for the investigation, production, and application of ASPs in functional foods and therapeutic agents. Moreover, this review also highlights the challenges of investigation and future considerations for holistic utilization.

A novel approach was developed for the synthesis of 5H-isochromeno [4,3-b]indolizin-5-ones (ICIDOs) 3 through a cascade reaction of 1,2,3-indantriones 1 with ethyl 2-(pyridine-2-yl)acetates 2. Various 5H-isochromeno [4,3-b]indolizin-5-ones were produced by heating of the mixture of 1,2,3-indantriones and ethyl 2-(pyridine-2-yl)acetates for approximately 8 ​h in an environmentally-friendly PEG200 solvent with catalyst of a few drops of acetic acid. This approach has several advantages such as the use of an environmentally-friendly solvent, simple and practical operation (with filtration and washing and no column chromatography separation), good yields (up to 91%), use of commercially available raw materials, diverse target compounds, and products with potential biological activity.

The practical applications of Li metal batteries (LMBs) have long been limited by the obstacles of low Coulombic efficiency (CE) and formation of dendrites on Li metal electrode. Herein, we demonstrated the synthesis of a novel three-dimensional (3D) nanostructured skeleton substrate composed of nitrogen-doped hollow carbon fiber/carbon nanosheets/ZnO (NHCF/CN/ZnO) using 2-methylimidazole (2-MIZ)-coated 3D cloth as a scaffold. The mechanism of formation of this novel hierarchical structure was investigated. The multilayered hierarchical structure and abundant lithiophilic nucleation sites of the substrate provide a stable environment for the deposition and stripping of lithium metal, thus preventing the generation of lithium dendrites. Consequently, the lithium anode based on the NHCF/CN/ZnO current collector demonstrated an excellent Coulombic efficiency of 96.47% after 400 cycles at 0.5 mA cm-2. The prepared NHCF/CN/ZnO/Li electrode also showed outstanding cycling performance of over 800 h and an ultralow voltage hysteresis of less than 30 mV in a symmetric cell at 5 mA cm-2 and 5 mAh cm-2. Even at a high loading of the cathode with 10.4 mg cm-2, the full cell of NHCF/CN/ZnO/Li anode with LiFePO4 can also work very well. Our work offers a path toward the facial preparation of 3D hierarchical structure for high-performance lithium metal batteries.

Figure-eight (lemniscular) shaped macrocycles, besides their esthetic beauty, often have interesting chiroptical properties. However, only limited figure-eight carbocyclic frameworks have been reported as yet and most of them have been acquired by dimerizing helicenes with inherently helical structures. Herein a novel figure-eight carbocyclic framework, lemniscular arylene ethynylene macrocycle (AEM), was firstly synthesized from non-helical precursors. By simply increasing the reactant concentration, intramolecular cyclization was effectively suppressed, while intermolecular cyclization was significantly increased to obtain figure-eight macrocycles in acceptable yields. Scanning tunneling microscopy (STM) investigation was firstly employed to confirm the figure-eight shape through molecular imaging. Furthermore, the figure-eight cyclization mechanism was systematically discussed. Interestingly, macrocycles bearing inner –NH2 groups (SPM-Q6-NH2 and SPM-Q12-NH2) showed a specific sensing behavior toward highly toxic Hg2+. Even more intriguing is that, compared to planar macrocycle SPM-Q6-NH2, its figure-eight dimer (SPM-Q12-NH2) exhibited much stronger complexation with Hg2+. This study opens up a new way to construct figure-eight conjugated carbocyclic macrocycles from an inherently non-helical precursor. More importantly, with this figure-eight AEM as a molecular platform, further structural derivations can be achieved through simple cycloaddition reactions with unsaturated bonds (ethynylene bonds and diyne bonds) or introducing donor–acceptor (D–A) structures.

Polymeric ionic liquids (PILs) with light-driven conductivity represent a new class of smart materials with potential applications as soft electronics, however the influence of counterion characteristics on their conducting properties remains unexplored. We synthesized a series of PILs based on copolymers of ethylene oxide and allyl glycidyl ether with different anions and light-responsive imidazolium-containing diarylethene (DAE) cations. This study shows that anion character impacts the photostationary state (PSS), magnitude of conductivity, and light-responsive properties of PILs. Compared with BF4−, anions featuring stronger cation–anion interaction (I−) and higher ratio of the ring-closed isomer at PSS (TFSI−) have a larger impact on the degree of change in ionic conductivity upon light irradiation. With this versatile synthetic platform, the electronic properties of the DAE cations can be non-invasively modulated by light with minimal structural change, providing the ability to study, in situ, cation–anion interaction without competing effects that arise from changes in polymer Tg or counterion size. These results are beneficial for understanding ion transport and structural design of smart light-responsive PILs.

Radiation enteritis is a common side effect of radiotherapy for abdominal and pelvic malignancies, which can lead to a decrease in patients’ tolerance to radiotherapy and the quality of life. It has been demonstrated that glycyrrhizin (GL) possesses significant anti-inflammatory activity. However, little is known about its anti-inflammatory effect in radiation enteritis. In the present study, we aimed to investigate the potential anti-inflammatory effects of GL on radiation enteritis and elucidate the possible underlying molecular mechanisms involved. The C57BL/6 mice were subjected to 6.5 Gy abdominal X-ray irradiation to establish a model of radiation enteritis. Hematoxylin and eosin staining was performed to analyze the pathological changes in the jejunum. The expression of TNF-α in the jejunum was analyzed by immunochemistry. The levels of inflammatory cytokines, such as TNF-α, IL-6, IL-1β, and HMGB1 in the serum were determined by enzyme-linked immunosorbent assay. The intestinal absorption capacity was tested using the D-xylose absorption assay. The levels of HMGB1 and TLR4 were analyzed by western blotting and immunofluorescence staining. We found that GL significantly alleviated the intestinal damage and reduced the levels of inflammatory cytokines, such as TNF-α, IL-6, IL-1β, and HMGB1 levels. Furthermore, the HMGB1/TLR4 signaling pathway was significantly downregulated by GL treatment. In conclusion, these findings indicate that GL has a protective effect against radiation enteritis through the inhibition of the intestinal damage and the inflammatory responses, as well as the HMGB1/TLR4 signaling pathway. Thereby, GL might be a potential therapeutic agent for the treatment of radiation enteritis.

Purpose Gene-targeting therapy provides a novel therapeutic approach for tumor treatment using genetically modified endothelial progenitor cells (EPCs) as cellular carriers. This study applied EPCs armed with cytosine deaminase (CD) and endostatin (ES) fusion gene in liver cancer to explore its therapeutic effect. Materials and methods EPCs from heart blood of male BALB/c nude mice were cultured and transfected with CD and ES fusion gene. Subsequently, these genetically modified cells were injected into mice bearing hepatoma through their tail veins. The tumor volumes and cell apoptosis were followed up. Results Tumor volume in the group injected CD/ES-EPCs greatly decreased. The positive rate of VEGF and CD31 in the tumor tissue was lowest in the CD/ES-EPC group. Furthermore, the number of apoptotic cells was highest in the CD/ES-EPC group. Conclusion The EPCs transfected with CD/ES inhibited tumor growth and preferentially induced tumor cell apoptosis, providing a novel methodology for cancer-targeting therapy.

Polymeric ionic liquids (PILs) have attracted considerable attention as electrolytes with high stability and mechanical durability. Light-responsive materials are enabling for a variety of future technologies owing to their remote and noninvasive manipulation, spatiotemporal control, and low environmental impact. To address this potential, responsive PIL materials based on diarylethene units were designed to undergo light-mediated conductivity changes. Key to this modulation is tuning of the cationic character of the imidazolium bridging unit upon photoswitching. Irradiation of these materials with UV light triggers a circa 70 % drop in conductivity in the solid state that can be recovered upon subsequent irradiation with visible light. This light-responsive ionic conductivity enables spatiotemporal and reversible patterning of PIL films using light. This modulation of ionic conductivity allows for the development of light-controlled electrical circuits and wearable photodetectors.

A novel desulfurization process was developed using hydroxyl-ferric oxide as the adsorbent and slurry bed as the reactor. The H2S removal performance and cycling behaviors of the adsorbent were inv...

A novel protocol for the construction of highly functionalized 2-(pyridin-3-yl)-chromeno[2,3-d]pyrimidines (PCPMDs) from 3-cyanochromone with 1,1-enediamines via an unprecedented cascade reaction has been developed by simply refluxing a mixture of 3-cyanochromone 1 and various types of 1,1-enediamines 2 under the catalysis of silver carbonate. As a result, a series of PCPMDs 3 were obtained through a novel cascade reaction involving an amazing electrocyclization mechanism of a cyano group with α,β-unsaturated nitriles. This reaction formation of PCPMDs was accompanied by the formation of four bonds and the cleavage of one bond in one step. This protocol can be used for the synthesis of various pyridin-3-yl-substituted complex pyrimidine derivatives, and it is suitable for combinatorial and parallel syntheses of PCPMD drugs or natural-like products.

One new 3,24-dinor-2,4-seco-ursane triterpene, rosanortriterpene C (1), together with four known compounds including 24-norursane-type nortriterpenes (2-3), 24-noroleanane-type nortriterpene (4), ursane-type triterpene (5), was isolated from the fruits of Rosa laevigata var. leiocapus. The new structure was elucidated through comprehensive spectroscopic analysis, including one dimensional (1D) and 2D NMR data, as well as electrospray ionization high resolution (HR-ESI) MS and IR spectrometry. Compounds 1-5 showed moderate anti-inflammatory activities against the production of nitric oxide (NO) in RAW264.7 cells stimulated by lipopolysaccharide (LPS) with IC50 values of 10.35 ± 0.92, 14.28 ± 1.20, 5.04 ± 1.43, 29.29 ± 3.64, and 14.37 ± 0.59 µM, respectively.

Bovine parainfluenza virus 3 (BPIV3) is a crucial causative agent of respiratory disease in young and adult cattle. No specific therapies are available for BPIV3 infection. Understanding the internalization pathway of the virus will provide a new strategy for the development of antiviral therapy. Here, the mechanism of BPIV3 entry into HeLa cells was analyzed using RNA silencing and pharmacological inhibitors. Treatment of HeLa cells with hypertonic medium prevented BPIV3 internalization. These results indicated that BPIV3 entered HeLa cells via receptor-mediated endocytosis. Moreover, removing cell membrane cholesterol through MβCD treatment hampered viral penetration but not viral replication. In addition, BPIV3 infection was inhibited by pretreatment with dynasore or chlorpromazine (CPZ) or knockdown of dynamin II or clathrin heavy chain. However, virus entry was unaffected by nystatin, EIPA, wortmannin, or cytochalasin D treatment or caveolin-1 knockdown. These data demonstrated that the entry of BPIV3 into HeLa cells was dependent on clathrin-mediated endocytosis but not on caveolae-mediated endocytosis or the macropinocytosis pathway. Many viruses are transported to endosomes, which provide an acidic environment and release their genome upon separation from primary endocytic vesicles. However, we found that BPIV3 infection required endosomal cathepsins, but not a low pH. In summary, we show, for the first time, that BPIV3 enters HeLa cells through the clathrin-mediated endocytosis pathway, presenting novel insights into the invasion mechanism of Paramyxoviridae.

Magnetic ionic liquids (MILs) exhibit high catalytic activity and selectivity in extractive and catalytic oxidative desulfurization (ECODS). In this study, a series of novel MILs, [Cn(mim)2]Cl2/mFeCl3 (n = 2, 4 or 6 and m = 1, 2 or 3), were prepared and introduced in ECODS of model oil with H2O2 as the oxidant. The catalytic performance of the prepared catalysts under different reaction parameters and their recyclability were evaluated. The results indicated that the acidity and hydrophobicity of the catalysts are the main factors affecting the oxidation/extraction process. [C4(mim)2]Cl2/2FeCl3 exhibited the highest desulfurization efficiency such that 97.07% of DBT removal was obtained in 10 min under optimum conditions. Moreover, [C4(mim)2]Cl2/2FeCl3 could be easily separated from the oil phase by an external magnetic field due to its strong magnetism and could be recycled 7 times with no significant decline in its activity after regeneration, thus exhibiting excellent recyclability. Finally, the desulfurization product was determined to be DBTO2 by FT-IR analysis and the hydroxyl radicals produced by Fe3+ and H2O2 played an important role in the desulfurization process. This study provides a new type of catalyst with high activity, selectivity, and stability for fuel desulfurization, which has potential industrial application prospects.

Enriching the synthetic routes of functionalized carbon dots (C dots) and expanding their application are necessary for promoting research into carbon-based nanomaterials. In this study, we develop a one-step and efficient method to prepare excitation-dependent multicolor emissive carbon dots (M-C dots) with quaternary ammonium functional groups via a solvothermal reaction of chloroform, diethylamine, and ammonium carbonate. Through detailed structural characterizations and further reactions of surface functional groups (such as reduction, oxidation, and hydrolysis) on M-C dots, the excitation-dependent tunable photoluminescence behaviors are proposed to come from the multiple emission domains on the surface. The prepared M-C dots possess antibacterial activity against Gram-positive bacteria and Gram-negative bacteria. And the antibacterial effects of M-C dots were investigated by destroying the bacterial cell walls/membranes via strongly electrostatic interactions between positively charged M-C dots and ...

With the fast development of peroxymonosulfate (PMS)-dominating processes in drinking water and wastewater treatment, residual PMS is easy to come across chlorine as these processes are usually followed by secondary chlorine disinfection. The synergistic effect of PMS and chlorine on the degradation of micro-organic pollutants is investigated by selecting acetaminophen (ACT) as a reference compound for the first time in this study. Unlike conventional PMS or chlorine activation which generates reactive species such as hydroxyl radical (HO•), sulfate radical (SO4•-), chlorine radical (Cl•), and singlet oxygen (1O2), the efficient ACT removal is attributed to the direct catalytic chlorination by PMS due to the significantly enhanced consumption of chlorine along with negligible change of PMS concentration at neutral condition, and the same reaction pathways in both PMS/chlorine and chlorine processes. The kinetic study demonstrates that ACT oxidation by PMS/chlorine follows second order reaction, and the degradation efficiency can be promoted at alkaline conditions with peak rate constants at pH 9.0-10.0. The presence of chloride can enhance the removal of ACT, while ammonium and humic acid significantly retard ACT degradation. Higher formation of selected disinfection by-products (DBPs) is observed in the PMS/chlorine process than in the sole chlorination. This study highlights the important role of PMS in organic pollutants degradation and DBPs formation during the chlorination process.

Overexpression of ANXA1 and EphA2 has been linked to various cancers and both proteins have attracted considerable attention for the development of new anticancer drugs. Here we report that ANXA1 competes with Cbl for binding EphA2 and increases its stability by inhibiting Cbl-mediated EphA2 ubiquitination and degradation in nasopharyngeal carcinoma (NPC). Binding of ANXA1 to EphA2 promoted NPC cell growth and metastasis in vitro and in vivo by elevating EphA2 levels and increasing activity of EphA2 oncogenic signaling (pS897-EphA2). Expression of ANXA1 and EphA2 was positively correlated and both were significantly higher in NPC tissues than in the normal nasopharyngeal epithelial tissues. Patients with high expression of both proteins presented poorer disease-free survival and overall survival relative to patients with high expression of one protein alone. Furthermore, amino acid residues 20-30aa and 28-30aa of the ANXA1 N-terminus bound EphA2. An 11 amino acid–long ANXA1-derived peptide (EYVQTVKSSKG) was developed on the basis of this N-terminal region, which disrupted the connection of ANXA1 with EphA2, successfully downregulating EphA2 expression and dramatically suppressing NPC cell oncogenicity in vitro and in mice. These findings suggest that ANXA1 promotes NPC growth and metastasis via binding and stabilization of EphA2 and present a strategy for targeting EphA2 degradation and treating NPC with a peptide. This therapeutic strategy may also be extended to other cancers with high expression of both proteins. Significance: These findings show that EphA2 is a potential target for NPC therapeutics and an ANXA1-derived peptide suppresses NPC growth and metastasis.

Recently, polysaccharides from Bletilla striata, a member of the orchidaceous family, aroused the wide interest of people, especially their isolation, chemical properties, and bioactivities. It is reported that these polysaccharides are the most important biologically active components of B. striata, exhibiting various biological activities, such as immunomodulatory, antioxidant, antifibrotic, and hemostatic effects. This review appraised the available literatures which described different aspects of B. striata polysaccharides, including the extraction, separation, purification, structural characterization, and biological activities. We expect to lay the foundation for further investigation of the application of B. striata polysaccharides in the field of functional foods and biomedicine.

Bigelovin (BigV) is a sesquiterpene lactone, isolated from Inula helianthus aquatica, which has been reported to induce apoptosis and show anti-inflammatory and anti-angiogenic activities. Nevertheless, the effects of BigV on liver cancer and the underlying mechanisms have not been investigated. In the study, we found that BigV exhibited potential anti-tumor activities against human liver cancer in vitro and in vivo. BigV reduced the cell proliferation and colony formation. BigV induced apoptosis through improving the cleavage of Caspase-3 and poly (ADP-ribose) polymerase 1 (PARP-1). The process was along with the activation of autophagy, as proved by the enhanced accumulation of autophagosomes, the microtubule-associated light chain 3B-II (LC3B-II) and Beclin-1, and p62 decrease. Further, the autophagy blockage markedly sensitized BigV-induced cell death, indicating the cytoprotective function of autophagy in liver cancer cell lines. In addition, BigV treatment inactivated the pathway of protein kinase B (AKT)/mammalian target of rapamycin (mTOR)/ribosomal protein S6 kinase (p70S6K). Of note, BigV-induced cell death was abolished by over-expressing the phosphorylation of mTOR. Intriguingly, the induction of apoptosis and autophagy were eliminated by the pretreatment of reactive oxygen species (ROS) scavenger N-acetyl- l -cysteine (NAC), suggesting that ROS played an important role in the regulation of BigV-induced cell death. Finally, in vivo studies demonstrated that BigV significantly suppressed the growth of HepG2 cancer xenograft tumors through the activation of apoptosis and autophagy in a dose-dependent manner with low systemic toxicity. In conclusion, the results revealed that BigV had significant antitumor effects against human liver cancer and it may potentially be used as a novel antitumor agent for the prevention of liver cancer.

Copper matrix composites containing different volume fractions of B4C particles (0–15%) were first fabricated by spark plasma sintering followed by hot rolling in atmospheric environments, then their microstructures, phase compositions, mechanical properties and sintering mechanism were investigated. It was found that B4C particles distributed relatively homogeneously in the copper matrix. Reaction products of CuC8 and B were observed and identified in the composite. Under increasing B4C particle content, the ultimate tensile, yield strength and elongation to fracture of the composites decreased. Failure mode of composites included: (1) the interfacial debonding and (2) the cleavage fracture of copper. Moreover, micro-discharge between the adjacent particles occurred, and its led to local high temperature at the interface.

Coordination polymers (CPs) are peculiar category of materials having multidimensional framework and could be used as selective and sensitive sensors for ions and molecules. In this regard, a new Zn(II)-based coordination polymer (CP) [Zn(H2L)(H2O)2]n (1) has been derived from 1,3-bis(3,5-dicarboxylphenoxy)benzene (H4L) ligand and spectroscopically characterized alongwith single crystal X-ray diffraction. The crystallographic experiments reveal the existence of 2D layer in 1. The CP retains its framework integrity in water and exhibits luminescent property. This newly designed CP has been used as luminescent sensor to detect antibiotics by the decline in its luminescence intensity. The sensing experiments indicated that the CP displays sensitive and selective sensing against nitrofurazone (NZF) with limit of detection (LOD) of 1.12 ppm and Ksv value of 2.41 × 103 M−1. The experimentally observed decline in the luminescence intensity of 1 in presence of antibiotics has been explained with the help of theoretical calculations.

Two new Ag(I) based coordination polymers (CPs), with formula [Ag2(H2L)(4,4′-bipy)2·2H2O] (1), and [Ag2(H2L)(bpz)2] (2) (H4L = 1,3-bis(3,5-dicarboxylphenoxy)benzene, 4,4′-bipy = 4,4′-bipyridine, and bpz = 3,3′,5,5′-tetramethyl-4,4′-bipyrazole) have been solvothermally synthesized and characterized. The single crystal X-ray structural analysis reveals that CPs 1 and 2 consist of 3D hydrogen-bonded organic framework with rectangle and grid channels, respectively. In addition, the photocatalytic properties of both 1 and 2 have been assessed under UV light against methyl orange (MO), rhodamine B (RB), methyl blue (MB), neutral red (NR), methylene blue (MB) are investigated in aqueous solutions. The results suggested that percentages of photocatalytic degradation toward MB, Rh B and MO in presence of 1 are 90.24%, 93.56% and 45.11%, respectively in 100 min. While in presence of 2 the percentage photodegradation of MB, Rh B and MO are 84.33%, 55.54% and 4.27% in 100 min. The plausible mechanistic pathways through which newly synthesized CPs executed photodegradation of these dyes have been explained with the aid of band gap calculations implementing density of states and partial density of states.

In this study, a sensitive monoclonal antibody (mAb) 3D5 against sparfloxacin (SPFX) was generated. Based on the mAb 3D5, an indirect competitive enzyme-linked immunosorbent assay (ic-ELISA) method was developed for the detection of SPFX in honey. The half maximal inhibitory concentration and limit of detection for the ic-ELISA method were 0.12 and 0.02 ng/mL, respectively. The experiments showed a negligible cross-reaction with other drugs. The average recovery rates for spiked SPFX honey extracts ranged from 90% to 101%, indicating an accepted accuracy. Furthermore, a lateral-flow immunochromatographic assay strip method with a cut-off value of 2 ng/mL was developed. Therefore, both of the developed methods are suitable for future use as rapid screening methods to detect and control the content of SPFX residues in honey samples.

One new ent-kaurane diterpene derivative (1), along with four known diterpenes, was isolated from the stems of Eurya chinensis R.Br. The structure of the new compound was established by extensive analysis of mass spectrometric and 1D and 2D NMR spectroscopic data. Compound 1 showed moderate anti-inflammatory activities with IC50 value of 8.12 μM. This is the first example of diterpenoids with 4-hydroxy-4-(2-hydroxyethyl)-1-hydroxyl-cyclohexanoyl substituent.

Surface-assisted laser desorption/ionization mass spectrometry (SALDI-MS) has become an indispensable tool in analysis of macromolecule and small molecule in solid and liquid samples. However, there were few studies focusing on the ionization mechanisms especially for the small molecules. In this work, the compounds of pyrene, coronene and rubrene with similar molecular structures were used to investigate the ionization mechanism via SALDI-MS. Additionally, the effect of laser power on product ions was also investigated. It was found that strong cluster ions peaks nM+ (M = pyrene, coronene) were observed for pyrene and coronene, and daughter ions of coronene by loss of C2H2 were also observed. On the contrary, no cluster ion was obtained for rubrene, only daughter ions with the losses of nC6H5 (n = 1, 2, 3) were acquired. Finally, the ionization mechanism was discussed. The formation of clusters of pyrene and coronene was attributed to the interaction of π-π bonds. For rubrene, the spatial barrier weakened the interaction of π-π bonds because the four phenyl groups were not on the same plane of skeleton structure, thus impeding the formation of cluster ions.

Two pairs of rare benzofuran glucoside epimers, indicuses A and B and indicuses C and D, three biogenetically related compounds indicuses E–G, and one coumarin indicus H, as well as 11 known compounds, were isolated from the bark of Streblus indicus (Bur.) Corner. The structures of indicuses A–H were elucidated by NMR and MS data, as well as by CD. ( S )-Marmesinin exhibited moderate antimicrobial activity in vitro against Bacillus subtilis and Saccharomyces cerevisiae . 7,8-Dihydroxy-3-(3-methyl-2-butenyl) coumarin, umbelliferone, and scopoletin displayed strong cytotoxic activity in vitro against human bladder carcinoma cell line EJ. The structure-activity relationships indicate that hydroxylation at C-7 in the cytotoxic compounds is crucial to their activities.

The single particle emission behaviours of our previously reported excitation-dependent full-colour carbon dots (F-C dots) have been analyzed by a single-particle fluorescence imaging technique. The co-localization of the F-C dots excited with different wavelengths shows that single F-C dots can also be excited with multiple energies. The co-localization of the F-C dots that emit at different colour regions under the same excitation wavelength or different excitation wavelengths shows that single F-C dots have a broad emission band from blue to red, but the emission intensities in different colour regions vary from one particle to another. So this study concretely proves that the full colour emissions are single particle behaviours; they are different from the other type of excitation dependent full-colour emission carbon dots whose full-colour behaviour originates from the large heterogeneity in both particle size and the structures of the ensemble. Then the origination of the full-colour emission at the single dot level was further studied by comparing the emission properties of the F-C dots and the small molecular byproducts, and it is found that the emissions of the dozens of molecular byproducts can also cover the full visible regions. And the emission positions of F-C dots are very similar to those of the byproducts at the same excitations, but they show different lifetimes. So a mechanism for the full colour emissions of F-C dots is proposed to originate from the hybridization of multiple small emissive molecules on the emissive carbon cores. This single particle level understanding of full-colour emission properties will pave the way towards the development of single dot imaging or tracking.

Four new lignans, (7′ R ,8′ S )-4,4'-Dimethoxy-strebluslignanol ( 1 ), 3'-Hydroxy-isostrebluslignaldehyde ( 2 ), 3,3'-Methylene-bis(4-hydroxybenzaldehyde) ( 3 ), and 4-Methoxy-isomagnaldehyde ( 4 ), and six known lignans ( 5 – 10) , were isolated from the roots of Streblus asper . The structures of these molecules were elucidated through various spectroscopic methods of analysis, including 1D and 2D NMR. The stereochemistry at the chiral centres was determined using the CD spectrum and from coupling constant and optical rotation data. Compounds 1–6 showed good antimicrobial activity against Saccharomyces cerevisiae (ATCC 9763), Bacillus subtilis (ATCC 6633), Pseudomonas aeruginosa (ATCC 9027), Escherichia coli (ATCC 11775), and Staphylococcus aureus (ATCC 25923), with MIC values ranging from 0.0150 to 0.0940 μM.

ANXA1 and EphA2 play a crucial role in cancer. Here, we report that ANXA1 competes with Cbl for binding EphA2 and increases its stability by inhibiting Cbl-mediated EphA2 ubiquitination degradation in nasopharyngeal carcinoma (NPC), leading to the enhanced NPC growth and metastasis in vitro and in vivo . In human NPC, patients with the high expression of both ANXA1 and EphA2 proteins have poorer disease-free survival and overall survival relative to patients with the high expression of one protein alone. Furthermore, based on the N-terminal amino acid 20-30 region of ANXA1 responsible for binding EphA2, we develop an ANXA1-derived peptide, named as A1 (20-30), that cuts its connection with EphA2, successfully downregulates EphA2 and suppresses NPC oncogenicity in vitro and in vivo. These findings reveal that ANXA1, via binding and stabilizing EphA2, drives NPC growth and metastasis, and present a strategy for targeting EphA2 degradation and treating NPC with a peptide.

Metal-organic framework material [Cd(tib)(dnbpdc) (H2O)]·2DMF·2H2O (1) [tib = 1, 3, 5-tris(1-imidazolyl)benzene, H2dnbpdc = 2, 2′-dinitro-4, 4′-biphenyldicarboxylic acid] was synthesized and characterized by Thermogravimetric analyses (TGA), Powder X-ray diffraction (PXRD) analyses and Bruker D8 Advance X-ray diffractometer. The results showed that 1 was a 1D chain structure to be joined together by hydrogen bonds to generate a 3D supramolecular structure. CO2 and N2 adsorption behavior of the material was studied. It is significative that 1 can selective sorption of CO2.

Self-assemblies of two newly designed pairs of hexylaniline derivatives connected with diynes (4J and 4JT2, 6J and 6JT2) at heptanoic acid/highly oriented pyrolytic graphite interface under ambient conditions have been studied by scanning tunneling microscopy. The functionalized π-conjugated molecules and solvent (heptanoic acid) were detected to co-assemble into different ordered networks. Density functional theory calculations were utilized to reveal the formation mechanisms of these nanoarrays and verify the synergism of van der Waals interactions and various hydrogen-bonding interactions in the self-assemblies.

The precise control of the conformations of biomolecules adsorbed on a surface at the single-molecule level is significant. However, it remains a huge challenge because of the complex structure and conformation diversity of biomolecules. Herein, a “nanopore-confined recognition” strategy is proposed to manipulate the adsorption of individual valinomycin molecules at room temperature through precise design of functionalized conjugated macrocycle (CPN8) supramolecular nanopores with complementary architectures and binding sites. We revealed that CPN8 prefers to selectively recognizing valinomycin with complementary architecture because of the strong synergistic interactions between the isopropyl groups of valinomycin and the amino groups of CPN8, with valinomycinhighly oriented pyrolytic graphite (HOPG) interactions. Our perspectives at the single-molecule level will provide valuable insights to improve the design of supramolecular nanopores for conformation-selective recognition of non-conjugated molecules.

One new Zn(Ⅱ) metal–organic framework, [Zn3(tib)2(BPT)2]·7H2O (ZZIT-1) [ZZIT-1 = Zhengzhou Institute of technology, tib = 1,3,5-tris(1-imidazolyl)benzene, H3BPT = biphenyl-3,4′,5-tricarboxylic acid], has been synthesized and characterized. ZZIT-1 is a two-fold interpenetrating 3D framework structure. The gas/vapor adsorption behavior and luminescence of the complex have been studied. Notably, ZZIT-1 can selectively adsorb CO2 over N2, and MeOH over EtOH, and these adsorption results have been corroborated by theoretical calculations. Most interestingly, ZZIT-1 shows unique selectivity for the detection of acetone through a fluorescence quenching mechanism in the solid state at room temperature.

Our previous study showed that ethanol exposure inhibited embryonic angiogenesis mainly due to the excessive stimulation of reactive oxygen species (ROS) production. In this study, we investigated whether sulforaphane (SFN), a known dietary bioactive compound, could ameliorate ethanol-suppressed angiogenesis using chick embryo angiogenesis models. Using chick yolk sac membrane (YSM) and chorioallantoic membrane (CAM) models, we demonstrated that administration of low concentrations of SFN (2.5–10 μM) alone increased angiogenesis, but high concentrations of SFN (20–40 μM) inhibited angiogenesis. SFN administration alleviated ethanol-suppressed angiogenesis and angiogenesis-related gene expression in both angiogenesis models. Ethanol exposure caused cell apoptosis in chick CAM, and the cell apoptosis could be remitted by administration of SFN. Subsequently, we demonstrated that the ethanol-induced increase in production of ROS and reduction of antioxidant enzymes’ activity were partially rescued by SFN. Similar results were obtained in endoplasmic reticulum (ER) stress determination, indicated by ATF6 and GRP78 expression or thapsigargin-induced ER stress in the presence or absence of SFN. Taken together, our experiments show that SFN administration can ameliorate ethanol-suppressed embryonic angiogenesis, and this is mainly achieved by alleviating excessive ROS production and ER stress. This study suggests that SFN, in appropriate concentrations, could be a potential candidate compound for preventing the negative impact of alcohol on angiogenesis.

In article 1702098, by Bart van Dam, Minjie Li, and co‐workers, single‐dot spectroscopy is used to show that individual carbon dots already exhibit excitation‐dependent photoluminescence, very similar to the ensemble of carbon dots. Characteristic excitation‐dependent emission spectra are identified, indicating the presence of multiple active emission sites within a carbon dot. This shows that it is possible to engineer different types of electron transitions in nanoscopic dimensions through facile chemical synthesis.

Carbon dots (CDs) are carbon-based fluorescent nanoparticles that can exhibit excitation-dependent photoluminescence (PL) “tunable” throughout the entire visible range, interesting for optoelectronic and imaging applications. The mechanism underlying this tunable emission remains largely debated, most prominently being ascribed to dot-to-dot variations that ultimately lead to excitation-dependent ensemble properties. Here, single-dot spectroscopy is used to elucidate the origin of the excitation-dependent PL of CDs. It is demonstrated that already single CDs exhibit excitation-dependent PL spectra, similar to those of the CD ensemble. The single dots, produced by a facile one-step synthesis from chloroform and diethylamine, exhibit emission spectra with several characteristic peaks differing in emission peak position and spectral width and shape, indicating the presence of distinct emission sites on the CDs. Based on previous work, these emission sites are related to the sp2 subregions in the carbon core, as well as the functional groups on the surface. These results confirm that it is possible to integrate and engineer different types of electronic transitions at the nanoscale on a single CD, making these CDs even more versatile than organic dyes or inorganic quantum dots and opening up new routes toward light-emission engineering.

A series of catalysts, ionic liquid-modified SBA-15 (denoted ILSBA) doped with H5PMo10V2O40 (HPMoV2) have been synthesized and characterized by XRD, FT-IR, 1H NMR, TG-DTA, and TEM. The catalyst was used for the removal of dibenzothiophene (DBT) in model oil combined with hydrogen peroxide (the oxidant) and acetonitrile (the phase-transfer agent). It was observed that the sulfur content of DBT can be reduced from 500 to 2 ppm by adjusting the amount of catalyst, the reaction temperatures and the reaction time. Besides, the catalyst activity for different sulfur compounds showed a huge difference which may be mainly affected by the electron densities of sulfur atom. Moreover, the catalyst can be recycled seven times without a significant loss in activity, which could be ascribed to the strong electrostatic interaction between ILSBA and HPMoV2. In addition, a postulated mechanism was proposed to reveal the oxidative desulfurization process.

A shape-persistent macrocycle consisting of 2,6-disubstituted aniline linked by acetylene, butadiyne, and an inner tetraethylene glycol bridge was prepared by Pd/Cu homocoupling oxidation reaction. The morphology of the resulting macrocycle was demonstrated and discussed, indicating the establishment of channels with amine functional groups inside the pores. Polarized optical microscopy (POM) observation of the macrocycle indicated the formation of liquid crystals (LCs) in the heating and cooling processes.

Nicotinamide adenine dinucleotide (NAD(+)) plays critical roles in energy metabolism, mitochondrial functions, calcium homeostasis and immunological functions. Our previous studies have found that NAD(+) administration can profoundly decrease ischemic brain injury and traumatic brain injury. Our recent study has also provided first direct evidence indicating that NAD(+) treatment can decrease cellular apoptosis, while the mechanisms underlying this protective effect remain unclear. In our current study, we determined the effects of NAD(+) treatment on several major factors in apoptosis and necrosis, including levels of Bax and nuclear translocation of apoptosis-inducing factor (AIF), as well as levels of DNA double-strand breaks (DSBs) and intracellular ATP in rotenone-treated differentiated PC12 cells. We found that NAD(+) treatment can markedly attenuate the rotenone-induced increases in the levels of Bax and nuclear translocation of AIF in the cells. We further found that NAD(+) treatment can significantly attenuate the rotenone-induced increase in the levels of DSBs and decrease in the intracellular ATP levels. Collectively, our study has suggested mechanisms underlying the preventive effects of NAD(+) on apoptosis, which has highlighted the therapeutic potential of NAD(+) for decreasing apoptotic changes in multiple major diseases.

We report a facile method to assemble a hierarchical and interconnected reduced graphene oxide/β-MnO2 (rGO/β-MnO2) nanobelt hybrid hydrogel by dispersion of presynthesized ultrathin β-MnO2 nanobelts (NBs) in graphene oxide (GO) precursor solution by a hydrothermal reaction. The microscopic structure of the three-dimensional (3D) hybrid hydrogel can be controlled by adjusting the content of the ultrathin β-MnO2 NBs, which exhibits the properties of low density, large specific surface area, and high compressive strength for the corresponding aerogel. Importantly, a typical hybrid hydrogel with 54.2% ultrathin β-MnO2 NBs displays a specific capacitance as high as 362 F g−1 at a current density of 1.0 A g−1, and even 282 F g−1 at 20 A g−1, which is three times higher than that of the pure rGO hydrogel (118 F g−1). Meanwhile, the typical hybrid hydrogel also shows outstanding cycling stability with 96.3% capacitance retention after 10 000 cycles of cyclic voltammetry (CV) scans. These findings open up the use of ultrathin NBs for the self-assembly of hybrid hydrogels as high performance supercapacitor devices in energy storage and conversion.

Chemical exfoliation method was applied to transform bulky assemblies of Au(I)–3-mercaptopropionate (MPA) coordination polymer (CP) to nanosheets and nanostrings using sodium citrate as an exfoliator. The exfoliation process and the structural characteristics of the Au(I)–MPA nanosheets and nanostrings were fully investigated by transmission electron microscopy, atomic force microscopy, UV–vis absorption spectroscopy, X-ray photoelectron spectroscopy and so on. As the structural rigidity and stability of the obtained Au(I)–MPA nanosheets, they are ideal precursors for fabrication of water soluble gold nanoparticle assemblies through progressive pyrolysis. This work provides a significant strategy toward the morphology regulation of CP nanostructures and will inspire further development of this research area.

Two new ent-kaurane diterpenes (1–2), together with five known analogs, were isolated from the stems of Eurya chinensis. The structures of new compounds were established by extensive analysis of mass spectrometric and 1D and 2D NMR spectroscopic data. Compound 3 exhibited noticeable anti-inflammatory activity as denoted by inhibiting LPS-induced nitric oxide (NO) production in RAW264.7 cells with an IC50 value of 7.82 μM. Compound 4 showed potent cytotoxic activity against human cancer cell lines NCI-H46, HepG2 and SW480 with IC50 values ranging from 7.45 to 8.54 μM.

Three new dimeric kavalactones, designated as diyangonins A–C (1–3), along with two known analogs were isolated from the roots of Piper methysticum. Their structures were elucidated by means of extensive analysis of their 1D, 2D NMR, and mass spectroscopic data. All these dimers possess a skeleton featuring a cyclobutane ring connecting two kavalactone units in head-to-tail or head-to-head mode. Compounds 1–5 were evaluated for their cytotoxic activities against human tumor cell lines.