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A new tyramine derivative, glycosamide A (1), together with two known amide alkaloids, N-benzoyltyramine methyl ether (2) and aurantiamide acetate (3), was isolated from the branches and leaves of Glycosmis craibii Tanaka. Their structures were elucidated through extensive 1D and 2D NMR and HR-ESI-MS spectroscopic analyses. All known compounds were isolated from the genus Glycosmis for the first time. Furthermore, the antiproliferative activities of all isolated alkaloids in vitro were evaluated. Compound 2 displayed weak antiproliferative activities against five human cancer cell lines, HL-60, SMMC-7721, A-549, MCF-7, and SW480.

Carrier recombination and charge loss at the interfaces of perovskite layers have a significant influence on high-performance planar perovskite solar cells (PSCs). We employed two-dimensional graphitic carbon nitride (g-C3N4), which is a heat-resistant n-type semiconductor, to modify the electron-transport layer/perovskite and perovskite/hole-transport layer interfaces, respectively. g-C3N4 could passivate the surface trap states of the methylammonium lead iodide light absorber through the formation of a Lewis adduct between N and the under-coordinated Pb, and it could also remarkably reduce the grain boundaries between perovskite crystal particles. A maximum power conversion efficiency (PCE) of 19.67% (Voc = 1.14 V, Jsc = 21.45 mA cm−2, FF = 0.807) could be obtained from planar PSCs with long-term stability using dual-positioned g-C3N4. Therefore, we consider that ultrathin semiconductor films with a Lewis base nature are suitable as dual-functional transport materials for devices. This work provides new guidance for dual-interfacial modification to improve the PCE and stability of devices.

Hydrogen energy, as an ideal renewable resource and green energy replacement, has attracted growing attention. However, constructing highly active and stable catalysts for hydrogen evolution from Formic acid (FA) is still a challenging issue for development of renewable hydrogen energy. Herein, we develop a facile defect engineering strategy to construct N-deficient ordered mesoporous graphitic carbon nitride coupled with AgPd nanoparticles (denoted as AgPd/N-ompg-C3N4). Impressively, the as-prepared Ag0.1Pd0.9/N-ompg-C3N4 catalyst exhibits remarkable activity with the Turnover frequency (TOF) value of 1588.2 h−1 and robust stability with only a slight decrease in activity after ten cycles. Such markedly enhanced catalytic performance of Ag0.1Pd0.9/N-ompg-C3N4 is mainly attributed to the unique structure of N-ompg-C3N4 with higher surface area and abundant surface defects, the strong metal − support interaction between AgPd and N-ompg-C3N4, and charge transfer from Pd to Ag. This study provides a novel and efficient strategy for designing efficient catalysts to drive the hydrogen evolution from FA.

Cyprotuoside C (1) and cyprotuoside D (2), two new cycloartane glycosides were isolated from the ethanol extract of the rhizomes of Cyperus rotundus. Their structures were identified as 24R-9,10-seco-cycloartan-1(10),9(11)-dien-3β,7β,24,25-tetraol 3-O-β-D-xylopyranosyl-(1→4)-[α-L-arabinopyranosyl-(1→6)]-β-D-glucopyranosyl-25-O-β-D-glucuronide (1) and 9,10-seco-cycloartan-1(10),9(11),23(24)-trien-3β,7β,25-triol 3-O-β-D-xylopyranosyl-(1→4)-{α-L-arabinopyranosyl-(1→6)-[α-L-rhamnopyranosyl-(1→2)]}-β-D-glucopyranosyl-25-O-β-D-glucuronide (2) by spectroscopic methods.

The removal of cationic dyes, methylene blue(MB) and rhodamine B(RB), and anionic dyes, methyl orange(MO) and eosin Y(EY), from aqueous solutions by adsorption using Cu2Se nanoparticles(Cu2SeNPs) was stu-died. The effects of the initial pH values, adsorbent doses, contact time, initial dye concentrations, salt concentrations, and operation temperatures on the adsorption capacities were investigated. The adsorption process was better fitted the Langmuir equation and pseudo-second-order kinetic model, and was spontaneous and endothermic as well. The adsorption mechanism was probably based on the electrostatic interactions and π-π interactions between Cu2SeNPs and dyes. For an adsorbent of 0.4 g/L of Cu2SeNPs, the adsorption capacities of 23.1(MB), 22.9(RB) and 23.9(EY) mg/g were achieved, respectively, with an initial dye concentration of 10 mg/g(pH=8 for MB and pH=4 for RB and EY) and a contact time of 120 min. The removal rate of MB was still 70.4% for Cu2SeNPs being reused in the 5th cycle. Furthermore, the recycled Cu2SeNPs produced from selenium nanoparticles adsorbing copper were also an ef-fective adsorbent for the removal of dyes. Cu2SeNPs showed great potential as a new adsorbent for dyes removal due to its good stability, functionalization and reusability.

Short DNA represents an important class of biomacromolecules that are widely applied in gene therapy, editing, and modulation. However, the development of simple and reliable methods for their intracellular delivery remains a challenge. Herein, we describe that seven water-soluble, homogeneous supramolecular organic frameworks (SOFs) with a well-defined pore size and high stability in water that can accomplish in situ inclusion of single-stranded (ss) and double-stranded (ds) DNA (21, 23, and 58 nt) and effective intracellular delivery (including two noncancerous and six cancerous cell lines). Fluorescence quenching experiments for single and double end-labeled ss- and ds-DNA support that the DNA sequences can be completely enveloped by the SOFs. Confocal laser scanning microscopy and flow cytometry reveal that five of the SOFs exhibit excellent delivery efficiencies that, in most of the studied cases, outperform the commercial standard Lipo2000, even at low SOF–nucleic acid ratios. In addition to high delivery efficiencies, the water-soluble, self-assembled SOF carriers have a variety of advantages, including convenient preparation, high stability, and in situ DNA inclusion, which are all critical for practical applications in nucleic acid delivery.

Intermolecular Stetter reaction of aromatic aldehydes with (E)-(2-nitrovinyl)cyclohexane catalyzed by thiazolium A has been developed. The reaction rate and efficiency are profoundly impacted by the presence of thiourea B. The reaction affords moderate to good yields of the Stetter product. Some factors influencing yield were discussed.

The surface acoustic wave (SAW) characteristics of Y-cut X propagating Pb(In 1/2 Nb 1/2 )O 3 -Pb(Mg 1/3 Nb 2/3 )O 3 -PbTiO 3 (YX-PIMNT) single crystals on a diamond substrate have been theoretically calculated. The simulated results show that the phase velocity of the shear horizontal (SH) SAW may be greatly enhanced from the 1350 m/s to 3350 m/s by reducing the thickness of the PIMNT from 0.5 λ to 0.05 λ , with a corresponding decrease in the electromechanical coupling factor ( K 2 ) from 73.6% to 19.6%. The dispersion curves of phase velocity and K 2 as a function of PIMNT thickness are given for the proposed layered structure. Besides the SH SAW, there are also higher order modes that would cause unwanted responses in the pass-band of wideband SAW filters. These were suppressed by properly controlling structural parameters including top electrode thickness, thickness and Euler angle (θ) of PIMNT substrate. The calculated results demonstrate the effectiveness of this approach to enlarge the phase velocity of the SH SAW without dramatically sacrificing its K 2 , which makes relaxor based ferroelectric single crystals promising for realizing ultra-wideband SAW devices working in ~ GHz range.

Adsorption energies, structural properties and electronic structures of atomic bromine adsorbed in on-surface sites on Mg(0 0 0 1) surface were investigated by using the density functional theory. Bromine coverages varying from 0.25 to 1.00 monolayer were considered. The most stable on-surface adsorption site is the fcc-hollow site in the whole coverage range. When the coverage increases, the adsorption energy decreases and the work function increases. On-surface bromine induces a contraction of the distance between the topmost and second Mg layers. The relative stability of surfaces with different Br coverages depends on the bromine chemical potential was analyzed, and the result suggests that bromine atom easily adsorbs on Mg(0 0 0 1) surface and the bulk MgBr 2 is energetically competitive. A comparison of the adsorbed F, Cl and Br on the Mg(0 0 0 1) surface was further investigated.

Six polyphenolic acids (1-6), including the three new compounds citriodolic acids A, B, and C (1-3), were isolated from the leaves of Eucalyptus citriodora. Their structures were elucidated by spectroscopic methods including one dimensional (1D)- and 2D-NMR, high-resolution electrospray ionization (HR-ESI)-MS, and circular dichroism (CD). The potential antivirus activity against respiratory syncytial virus (RSV) of all the isolated compounds was evaluated.

Based on bioactive screening results, two new iridoid glycosides, named rotunduside G (1) and rotunduside H (2), were isolated from the rhizomes of Cyperus rotundus, together with four known ones, negundoside (3), nishindaside (4), isooleuropein (5) and neonuezhenide (6). Their structures were elucidated on the basis of spectroscopic methods and from literature values. In mice models of despair, 1 and 2 showed significant antidepressant activity.

Two dimensional graphitic carbon nitride nanosheets (2D CNNs), as novel types of emerging materials, have aroused considerable research enthusiasm in recent years. Herein, we describe for the first time a new application of 2D CNNs as an ideal scaffold for synthesizing AgPd/2D CNNs through a facile one-step reduction method and further utilized it as catalysts toward photocatalytic hydrogen generation from FA under visible light (λ > 400 nm). Benefiting from plasmonic and Mott-Schottky, alloying effects, as well as the unique 2D nanosheets structure with a high surface area, the resultant Ag0.1Pd0.9/2D CNNs affords superior performance under visible light, including 100% H2 selectivity, 100% conversion, cycle performance, hydrogen evolution rate of 231.6 mmol h−1and the corresponding TOF value of 2936.8 h−1, which is 1.87 times and 3.5-fold higher than that of Ag0.1Pd0.9/2D CNNs under no light (1573.5 h−1) and that of Ag0.1Pd0.9/CN (837.2 h−1) under visible light, respectively, even better than most of the noble metal heterogeneous catalysts. This study not only throws light on modulating the structure of g-C3N4 to enhance the photocatalytic activity toward hydrogen evolution reaction but also offers a versatile method for developing high-performance photocatalyst for hydrogen economy and other applications.

A novel iron-catalyzed radical cyclization of olefinic dicarbonyl compounds with benzyl hydrocarbons has been developed. This protocol provides ready access to a variety of dihydrofurans containing a quaternary carbon center in moderate to good yields. Furthermore, this reaction could also be further expanded to other types of substrates containing unactivated Csp(3)-H bonds, such as ethers and alkanes.

Citrioside A, a new flavonoid glycoside, has been isolated from the n-butanol soluble fraction of Eucalyptus citriodora, along with five flavonoid glycosides, reported for the first time from Eucalyptus citriodora. Their structures were elucidated on the basis of spectroscopic methods and from literature values.

A new flavone C-glycoside, 5,7-dihydroxy-4′-methoxy-8-C-[2″-(2″′-methylbutyryl)]-β-D-glucopyranosyl flavone (1), was isolated from the rhizomes of Cyperus rotundus. Its chemical structure was elucidated on the basis of UV, IR, MS, and NMR spectroscopic analyses. Compound 1 showed moderate inhibitory activity against MRB in the test, with an IC50 value of approximately 56.03 μM.

Novel tricyclic fluoroquinolones, [1,2,4]triazolo[3,4-h][1,8]naphthyridine-8-one-7-carboxylic acid derivatives 4a – 4h bearing carrying a functional Mannich-base moiety at the C-8 position, were synthesized and evaluated for their antimicrobial activity. The results showed that some compounds with a piperazine side chain exhibited comparable or better antibacterial activity than comparator cirprofloxacin. Furthermore, the targeted compounds also displayed a broad spectrum of activity against resistant strains including both Gram-negative and Gram-positive bacteria. In particular, compound 4h showed an MIC of 0.25 μg/mL in antibacterial assay against multiple drug-resistant Escherichia coli , which represents an about 30-fold increase of potency compared to ciprofloxacin. Thus, their excellent antibacterial activity against resistant strains suggests that triazole-fused fluoroquinolones warrant further optimization as novel anti-infective chemotherapies.

Radically changing benzyls: An efficient method for the benzylarylation of activated alkenes has been developed through a copper-catalyzed tandem radical addition/cyclization strategy (see scheme). This oxidative coupling between acrylamides and benzylic hydrocarbons provides access to diverse alkyl-substituted oxindoles in good to excellent yields. A variety of functional groups were tolerated in this transformation (TBPB = tert-butylperoxy benzoate).

Shijiazhuang Academy of Agriculture and Forestry Sciences, Shijiazhuang, 050041, P.R. ChinaReceived December 5, 2014, Accepted March 24, 2014Key Words : Cyperus rotundus L., Rotunduside C, Macrophages respiratory burstThe rhizome of Cyperus rotundus is a kind of traditionalChinese medicine named “Xiangfuzi”, which is widely usedin folk medicine as an anti-inflammatory, antidepressant,antipyretic, analgesic, and antiemetic remedy for dysenteryand women’s diseases.

Antistatic composites of poly(ethylene terephthalate) (PET) and tetrapod-shaped ZnO whisker (ZnOw), the surface of which was treated with a coupling agent, were prepared by melt-mixing using a twin screw extruder. The structure and morphology of the blends were examined by FTIR and SEM. Antistatic performance and the effect of ZnOw loading levels were investigated. The conductive mechanism of PET/ZnOw composites is presented, which can be classified into tunnel effect, discharging effect at the pinpoint and conductive network. The simple formula of critical volume fraction (vc) for ZnOw forming conductive network is proposed, based on the actual processing conduction. Comparison of the theory value to the experimental data showed a close agreement. POLYM. COMPOS., 2009. © 2008 Society of Plastics Engineers

One new triterpene saponin, named ilexgenin A2 (1), and a known triterpene saponin, 3β,19α-dihydroxyurs-12-en-24,28-dioic acid 24,28-di-O-β-D-glucopyranoside (2), were isolated from the leaves of Ilex pubescens. Their chemical structures were elucidated on the basis of UV, IR, MS, and NMR spectroscopic analyses coupled with chemical degradation. The results of preliminary pharmacological research show that 1 presents definite XOD inhibitory activity.

Electrosynthesis of glyoxylic acid by electroreduction of oxalic acid has long been well known. However, attempts to commercialize the process have encountered problems due to rapid deactivation of the cathode. The cathode activity can be continuously restored by adding small amounts of chemical activators to the catholyte. In this paper the structural effect of chemical activator on electrode reaction is studied. The results show that (1) It is the cation of the chemical activator, but not the anion that affects the current efficiency and the reaction selectivity. (2) The more symmetrical the cation, or the shorter the longest alkyl chain, the higher the current efficiency and the reaction selectivity become. (3) Mechanism of the activation is discussed. Adsorption of the cations of the activator on the cathode surface protects the electrode. (4) Quantitative characterization of the activator molecule is given using some topological indices, with which the activation ability can be predicted, and screening of the proper activator is made possible.

The copper-catalyzed tandem oxidative cyclization of cinnamamides with benzyl hydrocarbons through the direct cross-dehydrogenative coupling of sp(3) and sp(2) C-H bonds has been developed. Satisfactorily, ethers, alcohols and alkanes could also be used instead of benzyl hydrocarbons in this transformation, which allows rapid access to diverse dihydroquinolinones in one step.

In the title compound, C(20)H(22)O(8)S, the dihedral angle between the two benzene rings is 81.6 (3)°. The benzene-connected portions of the alk-oxy substituents are almost coplanar with their respective rings [C-C-O-C torsion angles of 174.77 (17) and -178.5 (4)°]. One of the butanoic acid groups is disordered over two conformations with a site-occupancy ratio 0.719 (6):0.281 (6). In the crystal, pairs of O-H⋯O hydrogen bonds link the mol-ecules into infinite zigzag chains along [130].