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In this work, a class of transition metal-modified MCM-41 mesoporous silica supported ionic liquids nanocatalysts were constructed and efficiently used as catalysts for the effective carboxylation of terminal alkynes through CO2 utilization. The main factors affecting the catalytic performance of carboxylation and its possible reaction mechanism were sufficiently discussed. The results showed that when the dosage was 0.2 g, the temperature was 40°C and the CO2 pressure was 0.3 MPa, the supported catalyst MCM-41@IL-Sm showed the optimal catalytic efficiency. The novel catalyst proved to be highly efficient for the sustainable synthesis of alkynyl carboxylic acids attributing good to excellent yields of 82%–95% within 7–12 h. Moreover, MCM-41@IL-Sm could be recycled and reused six times without noticeable decrease in catalytic activity from two-phase system under external heterogeneous field. The application of supported ionic liquids in the field of carbon dioxide carboxylation has injected a new power source for the efficient and effective production of value-added chemicals from waste CO2. [ABSTRACT FROM AUTHOR]

In this study, we report a successful strategy for the generation of a type of multifunctional heterogeneous supported ionic liquids catalysts. The synthesized supported ionic liquids (Fe‐MCM‐41/IL) were used in the catalytic cyclocondensation of 2‐aminobenzamide and various ketones and aldehydes towards the efficient synthesis of the dihydroquinazolinones under green conditions. The influence of the different catalysts and reaction parameters on the catalytic behaviors were sufficiently investigated. The supported catalyst (2)Fe‐MCM‐41/IL(0.6) showed the optimal catalytic efficiency. A hot filtration experiment revealed that the reaction proceeded in a heterogeneous pathway. The catalytic activity of (2)Fe‐MCM‐41/IL(0.6) could be maintained efficiently after recycling up to five consecutive runs under the optimized reaction conditions. Merits of this meticulously designed protocol are the use of novel supported catalyst, easy work‐up process, feasibility and sustainability, indicating its potential industrial application prospect. [ABSTRACT FROM AUTHOR]

A type of MCM-41 supported dual imidazolium ionic liquids have been synthesized and efficiently used as catalysts in the sustainable chemical conversion of CO2 and epoxides into cyclic carbonates. It was shown that the highest efficiency was achieved in the cycloaddition of a variety of epoxides and CO2 in the presence of the MCM-41@DILSCN solid catalyst under mild conditions. More interestingly, the catalyst was stable, very active, robust, and displayed good recyclability without significant loss of catalytic activity after six consecutive cycles during the process. Overall, the present protocol of synthesizing cyclic carbonates under solvent free conditions using MCM-41@DILSCN is promising for industrial applications. [ABSTRACT FROM AUTHOR]

[Display omitted] • Early diagnoses of diseases require us to detection tiny biomarkers. • Nanofluidic devices magnify signal of tiny biomarkers. • Nanofluidic devices hold a promise for in portable sensors and POC detection. Disease diagnosis, especially for early diagnosis, is the most effective method to prevent disease development and mortality. However, low abundance clinical biomarkers in samples pose a challenge to sensitivity and selectivity of early diagnosis. Nanoconfined environment provides unique effects, including ionic current rectification, steric effect, and selective transport, etc., which could be applied to magnify signal and enhance sensitivity in discrimination of biomarkers on electrochemical (EC) sensors. Therefore, nanofluidic EC sensors have experienced a speedy development in ultra-sensitive sensing. In this review, we highlight the application of nanofluidic EC sensors with different structures (nanocapillary, nanoporous membrane, nanopore, and micro/nanofluidic chip) in biomarkers detection. Different types of nanofluidic devices, mechanism of nanoconfined effect, and their applications in ultra-sensitive sensing are summarized and discussed. Finally, this review provides a respective about nanofluidic EC sensors in biomarkers detection and helps the understanding nanoconfined effect for developing new analysis. [ABSTRACT FROM AUTHOR]

Global warming and climate change concerns are triggering worldwide interest for sustainable transformation of CO2 into useful chemicals. Here, a new and efficient multifunctional catalytic system for the cycloaddition of carbon dioxide with epoxides to synthesize cyclic carbonates under mild and solvent-free reaction conditions has been developed. The catalytic tests revealed that [P12,4,4,4]Br/MIL-53(Cr) (MIL: Materials of Institut Lavoisier) was the best and powerful catalytic system in the cycloaddition with excellent yields (96-99%) under solvent-free condition and 100 °C, 1.0 MPa for 2-3 h. The synergistic effect of anion and cation of ionic liquid [P12,4,4,4]Br as well as the chromium site of cocatalyst MIL-53(Cr) contributed to the excellent catalytic activity. The present catalytic system has several unique features such as simple operation, good to excellent yields, high catalytic activity, environmentally benign and safe. This study provides a sustainable and efficient synergistic strategy for chemical carbon dioxide fixation via the combination of ionic liquids and metal-organic frameworks. [ABSTRACT FROM AUTHOR]

A series of functionalized ionic liquids immobilized onto SBA‐15 mesoporous materials were prepared, characterized and evaluated as catalysts in cycloaddition of CO2 to epoxides. Most of these immobilized ILs perform well in the reaction, especially the multifunctional titanium incorporated SBA‐15 immobilized heterogeneous catalysts Ti‐SBA‐15@ILClCH2COO(0.5) and Al‐SBA‐15@ILClCH2COO(0.5). The catalytic tests revealed that Ti‐SBA‐15@ILClCH2COO(0.5) was the best and powerful catalyst in the cycloaddition for the preparation of cyclic carbonates with high to excellent yields. The heterogeneous catalyst can be easily separated from the reaction mixture by filtration and reused in six consecutive cycles without significant loss in catalytic activity. The studies demonstrate that the well designed supported catalysts via cooperative catalysis of the supported carrier, anion sites of ILs is a promising platform for construction of novel and highly efficient catalytic transformation systems. [ABSTRACT FROM AUTHOR]

Abstract: A supported ionic liquid ILCF3SO3@SiO2 was synthesized and used as a highly efficient catalyst in the Paal-Knorr reaction for the preparation of pyrroles. The heterogeneous catalyst could be easily recovered and recycled for five times without noticeable loss of catalytic activity. Also a possible reaction mechanism is provided.Graphical Abstract: [ABSTRACT FROM AUTHOR]

Nano‐silica supported ionic liquids composed of alkyl carbon chain and transition metal chlorides anions have been prepared and successfully applied as a heterogeneous catalyst in the direct aldehyde C‐H activation. Catalytic results indicated that nano‐SiO2 supported ionic liquid consisting C12 alkyl carbon chain and CoCl3 anion nano‐SiO2@CoCl3‐C12IL showed excellent catalytic properties with good to excellent yields towards the desired aryl ketones. The excellent recyclability of the supported catalyst, mild reaction conditions, low catalyst loading, and operational simplicity are the important features of this methodology. [ABSTRACT FROM AUTHOR]

A series of silica-supported functionalized ionic liquids catalysts have been prepared and tested in the oxidative conversion of alcohols to nitriles with HO as the oxidant. The features of this heterogeneous reaction system were studied by tuning various reaction parameters including catalyst selection, amount of the catalyst, and effect of solvents. Among the catalysts, FeCl-IL-SiO exhibited the highest efficiency in direct oxidation of alcohols to nitriles under the optimized condition along with good recycle performance. Also, a possible catalytic mechanism is provided. Graphical abstract: [ABSTRACT FROM AUTHOR]

A general and efficient catalytic system for Pd 2 (dba) 3 -catalyzed ligand-free Suzuki cross-coupling reactions was developed. The cross-couplings of a wide range of aryl halides with various arylboronic acids were feasible under mild conditions in environmental friendly [hmim]NTf 2 /supercritical CO 2 biphasic system employing K 2 CO 3 as a base, which provided in good to high yields to the corresponding products. The catalytic system could be recycled and reused without significant loss of catalytic activity. Additionally, a possible mechanism of the Suzuki cross-coupling reaction is depicted in this paper. [ABSTRACT FROM AUTHOR]

In this work, a functionalizing active species 4-methylbenzenesulfonic acid-based IL on silica gel (IL-SOH-SiO) has been prepared, and characterized by FT-IR, XRD, TGA, SEM and EDX spectra. Then, IL-SOH-SiO was utilized as an efficient and heterogeneous catalyst for the synthesis of indoles via the one-pot Fischer reaction of phenyl hydrazines with ketones or aldehydes at room temperature. The heterogeneous catalyst could be recovered easily by filtration and reused many times without significant loss of its catalytic activity. Graphical Abstract: [ABSTRACT FROM AUTHOR]

A simple, efficient, and eco-friendly procedure for the epoxidation of alkenes to epoxides with HO catalyzed by Co(OAc) in ionic liquid [Cpy][PF] has been developed. The reactions were carried out with alkene, Co(OAc) (0.1 mmol), [Cpy][PF] (10 mL), and HO (30 %, 11 mmol) at room temperature for 2-6 h. This atom-economical protocol affords the target products in good to high yields (88-98 %). The products can be separated by a simple extraction with organic solvent, and the catalytic system can be recycled and reused without loss of catalytic activity. Graphical abstract: A simple, efficient, and eco-friendly procedure for the epoxidation of alkenes to epoxides with HO catalyzed by Co(OAc) in ionic liquid [Cpy][PF] has been developed.[Figure not available: see fulltext.] [ABSTRACT FROM AUTHOR]

A simple, efficient, and ecofriendly procedure for the aerobic oxidation of alcohols to aldehydes and ketones in the presence of In(NO 3 ) 3 /[C 12 mim][FeBr 4 ] in aqueous media has been developed. The oxidation reactions afford the target products in good to high yields and no over-oxidation was observed. The products can be separated by a simple extraction with dichloromethane, and the system can be recycled and reused without loss of activity. [ABSTRACT FROM AUTHOR]

A simple and efficient method for the oxidation of primary and secondary alcohols to the corresponding aldehydes and ketones with HO/(NH4)MoO4HO using the PEG-DIL/methylcyclohexane temperature-dependent biphasic system has been developed. The product can be easily isolated by a simple decantation, and the catalytic system can be recycled or reused without loss of catalytic activity. Graphical Abstract: [Figure not available: see fulltext.] [ABSTRACT FROM AUTHOR]

A simple, green and efficient protocol for the selective C-3 functionalization of indoles with ketones and olefins via Ce(OAc)3-TBHP mediated oxidative C–H activation in the presence of β-cyclodextrin in water has been developed. This atom-economical protocol affords the target products in good to excellent yields. The products can be separated by a simple extraction with organic solvent, and the catalytic system can be recycled and reused without loss of catalytic activity. [ABSTRACT FROM AUTHOR]

An efficient, experimentally simple, and convenient procedure for the C-O coupling of organic halides with phenols and alcohols in a PEG1000-DAIL[CdCl3]-toluene temperature-dependent biphasic system has been developed. The product can be easily isolated by a simple decantation, and the catalytic system can be recycled and reused without loss of catalytic activity. On a mis au point une méthode commode, efficace et expérimentalement simple de faire un couplage C-O d'halogénures organiques avec des phénols et des alcools dans un système biophysique PEG1000-DAIL[CdCl3]-toluène qui varie avec la température. Les produits peuvent être facilement isolés par une simple décantation et le système catalytique peut être recyclé et réutilisé dans perte d'activité catalytique. [ABSTRACT FROM AUTHOR]

A facile and efficient synthesis of bibenzyl and biaryl derivatives by reductive homocoupling reaction is described. Treatment of benzyl and aryl halides with metallic zinc and copper powder in the presence of a catalytic amount of [Cmim][CuCl] under ligand- and base-free conditions gives the corresponding bibenzyls and biaryls in good to high yields. The product can be isolated by a simple extraction with organic solvent, and the catalytic system can be recycled or reused without any significant loss of catalytic activity. Graphical Abstract: [Figure not available: see fulltext.] [ABSTRACT FROM AUTHOR]

Abstract: A simple, mild, and efficient procedure for the oxidation of organic halides to aldehydes and ketones with H5IO6 in ionic liquid [C12mim][FeCl4] has been developed. The oxidation reactions afford the target products in good to high yields and no overoxidation was observed. The products can be separated by a simple extraction with organic solvent, and the catalytic system can be recycled and reused without loss of catalytic activity. [Copyright &y& Elsevier]

Abstract: The effect of surface microstructures of microchannels on the separation efficiency in microchip electrophoresis has been studied. In order to understand the influence of the surface microstructures on the microchip electrophoresis performance, a thermostatic system was designed and fabricated for precisely control of the chip temperature since the surrounding temperature causes a significant effect on the separation efficiency. The periodically ordered microstructures (dams) of different sizes were fabricated on the microchannels by a simple printing process using different gray levels of the vector graphic software. And the influence of dam sizes in microchannels on the separation efficiency was evaluated by using the number of theoretical plates (N) and the relative resolution (Rs’). Analyzing the variations of mixing elements caused by the periodically ordered dams in the separate channel and elution time, we found that with small dam size fabricated at low gray level of ca. 30%, the resolution of dopamine and epinephrine increased slightly, while it decreased obviously with larger dam sizes especially fabricated at gray level of 50%. [Copyright &y& Elsevier]

Abstract: The Ag/MgO(001) system has been studied by first-principle method based on density function theory, adsorption of Ag n (n =1–5) clusters on MgO(001) surface have been investigated to elucidate the initial stage of Ag atom deposition on MgO surface. It was found that the preferential adsorption site for an isolated Ag atom is directly above the surface oxygen atom and a weak bond is formed. Various structural configurations have been examined for the Ag n clusters and standing planar structures were found to be energetically more stable than flat planar structures. Energy and electronic properties revealed that with the increase of Ag coverage, the interaction of adsorbate–adsorbate bonds prevails over adsorbate–substrate bonds, leading to a Volmer–Weber mode deposition. [Copyright &y& Elsevier]

Abstract: Although most of enzyme catalytic reactions are specific, the amperometric detection of the enzymatic reaction products is largely nonselective. How to improve the detection selectivity of the enzyme-based electrochemical biosensors has to be considered in the sensor fabrication procedures. Herein, a highly selective amperometric glucose biosensor based on the concept of diffusion layer gap electrode pair which we previously proposed was designed. In this biosensor, a gold tube coated with a conductive layer of glucose oxidase/Nafion/graphite was used to create an interference-free region in its diffusion layer by electrochemically oxidizing the interfering electroactive species at proper potentials. A Pt probe electrode was located in this diffusion layer of the tube electrode to selectively detect hydrogen peroxide generated from the enzyme catalytic oxidation of glucose in the presence of oxygen in the solution. In practical performance of the microdevice, parameters influencing the interference-removing efficiency, including the tip-tube opening distance, the tube electrode potential and the electrolyzing time had been investigated systematically. Results showed that glucose detection free from interferents could be achieved at the electrolyzing time of 30s, the tip-tube opening distance of 3mm and the tube electrode potential of 0.4V. The electrochemical response showed linear dependence on the concentration of glucose in the range of 1×10−5 to 4×10−3 M (the correlation coefficient: 0.9936, without interferents; 0.9995, with interferents). In addition, the effectiveness of this device was confirmed by numerical simulation using a model system of a solution containing interferents. The simulated results showed good agreement with the experimental data. [Copyright &y& Elsevier]

Abstract: Generally speaking, measurement of hydroxylated radical products of salicylic acid requires a fussy separation process. In this study, we describe a simple method to electrochemically detect hydroxyl radicals ( 4-hydroxybenzoic acid (4-HBA) as the The erated by the Fenton reaction from iron (II) sulfate and hydrogen peroxide in a phosphate buffer solution. Experimental results show that our method can detect the igh sensitivity without any separation process. The differential pulse voltammetric responses show a linear dependence on the concentration of ange of 2.0×10−6 and 1.0×10−3 M with a determination limit down to 5.0×10−7 M. As a demonstration, the kinetics of the Fenton reaction was mapped by measuring the reaction product of hydroxyl radical trapped by 4-HBA. The result is in good agreement with that reported previously. All the results show that the present approach could provide a simple, inexpensive and promising method for biomedicine and iatrology. [Copyright &y& Elsevier]

Abstract: We describe a novel photochemical method to synthesize compacted Prussian blue (PB) film from an acidic ferricyanide solution. The key step is the photochemical reduction of ferricyanide ion to ferrocyanide ion that subsequently coordinates with the free ferric ion dissociated from the ferricyanide in acidic medium to form Prussian blue on the illuminated electrode surface. The prepared PB film electrode shows high electrocatalytic activity towards the reduction of hydrogen peroxide and the amperometric responses show a linear dependence on the concentration of hydrogen peroxide in a range of 1.0×10−6 to 1.2×10−3 M with a detection limit down to 4×10−7 M. The present photochemical method provides a simple and promising route for the local fabrication of patterned molecular magnets, ion-selective sensors, and electro- or photochromic devices. [Copyright &y& Elsevier]

An immobilized benzotriazolium ionic liquid system has been developed for the efficient catalytic transformation of CO2 to cyclic carbonates without using any co‐catalyst or solvent. Two novel multifunctional periodic mesoporous organosilica supported benzotriazolium ionic liquids PMO‐ILTiCl5 and PMO‐ILSnCl5 were prepared, characterized and demonstrated excellent catalytic activity in the cycloaddition of CO2 with epoxides. The superior catalytic performance was observed for PMO‐ILTiCl5 in the synthesis of cyclic carbonates with high yields and selectivities. Furthermore, the catalyst PMO‐ILTiCl5 could be separated readily and reuse for at least five successful times without obvious losses in its catalytic activity, owing to the presence of intramolecular synergistic effect between active hydroxyl sites and TiCl5 nucleophile and thus provide sufficiently stable catalytic sites. Therefore, this work provided a novel strategy for highly efficient and environmentally benign catalytic conversion of CO2 to cyclic carbonates. [ABSTRACT FROM AUTHOR]

The mitochondrial genome of the German waspVespula germanica(Fabricius, 1793) (Hymenoptera: Vespidae) (GenBank accession no. KR703583) was sequenced in the study. It represents the first mitochondrial genome from the genusVespula. There are totally 163 42 bp in the currently sequenced portion of the genome, containing 13 protein-coding, two rRNA, and 18 tRNA genes and a partial A + T-rich region. Four tRNA genes oftrnI, trnQ, trnMandtrnYlocated at the downstream of the A + T-rich region were failed to sequence. At least two rearrangement events occurred in the sequenced region compared with the pupative ancestral arrangement of insects, corresponding to the translocation or remote inversion oftnnYfromtrnW-trnC-trnYcluster to the region oftrnI-trnQ-trnMcluster and translocation oftrnL1from the downstream to the upstream ofnad1gene. All protein-coding genes start with ATN codons. Twelve and one protein-coding genes stop with termination codon TAA and T, respectively. Phylogenetic analysis using the Bayesian method based on all codon positions of the 13 protein-coding genes supports the monophyly of Vespidae and Formicidae. Within the Formicidae, the Myrmicinae and Formicinae form a sister group and then sister to the Dolichoderinae, while within the Vespidae, the Eumeninae sister to the lineage of Vespinae + Polistinae. [ABSTRACT FROM AUTHOR]

An ionic liquid is used as a catalyst for the synthesis of cyclic carbonates (III) from epoxides (I) and carbon dioxide. [ABSTRACT FROM AUTHOR]

An eco-friendly, easy, and efficient recyclable approach to carboxylic esters, acids, and lactones via oxidation is introduced. [ABSTRACT FROM AUTHOR]

The article presents chemical equations related to the article "Efficient and Convenient Oxidation of Sulfides to Sulfoxides with Molecular Oxygen Catalyzed by Mn(OAc)2 in Ionic Liquid [C12mim][NO3]" by D. Fang and others, published in the "Royal Society of Chemistry Advances" in 2014.

Periodic mesoporous organosilica (PMO) supported ionic liquids with high catalytic ability were prepared and tested in synthesis of 2‐oxazolidinones from the three‐component cycloaddition reactions of CO2, aryl amines and epoxide. The functionalized PMO material PMO@TZ‐ILSmCl4 revealed the most excellent catalytic performance than PMO@TZ‐ILLaCl4 during the catalytic synthesis of 2‐oxazolidinones. Different parameters such as catalyst loading, temperature, CO2 pressure and reaction time were also investigated. Good to excellent yields for 2‐oxazolidinones and stable reusability were reached in the CO2 cycloaddition under solvent‐ /ligand‐free conditions. This work provides a useful route to design novel and highly efficient catalytic systems for the transformation of CO2 into other valuable 2‐oxazolidinones. [ABSTRACT FROM AUTHOR]

Abstract: An efficient method for the selective hydration of nitrile to amide by employing inexpensive copper salt catalyst and commercially available acetaldoxime in environmentally friendly water is described. Under this protocol, nitriles including aromatic nitriles, heterocyclic nitriles and aliphatic nitriles were converted into the corresponding amides in good to excellent yields. [Copyright &y& Elsevier]

Abstract: The structural distortion of -structured MnO and FeO under high pressure is investigated using ab initio methods within GGA and GGA+U approximations. Present calculations indicated that the ordinary density-functional calculation overestimated the structural distortion of MnO and FeO under pressure. When the strong electronic correlations are included in the form of GGA+U, a reasonable description of the structural distortion under high pressure can be obtained. The overestimation of exchange interactions in ordinary DFT calculations may be the most important reason for the overestimation of structural distortion. [Copyright &y& Elsevier]

Abstract: Rapid separation and determination of acetaminophen and its hydrolysate with end-channel electrochemical (EC) detection integrated on a plastified poly(ethylene terephthalate) (PET)-toner microchip capillary electrophoresis (CE) system was investigated. In this separation and detection system, a Pt ultramicroelectrode integrated on a three-dimensional adjustor was used as working electrode. Factors influencing the separation and detection were investigated and optimized. Results show that acetaminophen and p-aminophenol can be well separated within 84s with R.S.D.<1% for migration time and R.S.D.<3.6% for detection current for both analytes. Detection limits for both analytes are determined to be 5.0μM (S/N=3). This method has been successfully applied to the detection of trace p-aminophenol in paracetamol tablets. The results demonstrate that the PET-toner microchips can obtain better performance than PDMS microfluidic devices but at much lower cost. [Copyright &y& Elsevier]

A new methodology for the highly efficient and atom‐economic oxidation of alcohols and benzylic compounds to the corresponding aldehydes and ketones with environmental‐friendly hydrogen peroxide using a magnetic MOF nanocatalyst has been developed. We demonstrated that the resulting magnetic nanocomposite CoFe2O4@SiO2@MIL‐53(Fe) can show excellent catalytic performances in the highly selective oxidation at room temperature, based on a synergetic effect between iron sites and CoFe2O4@SiO2. The nanocatalyst offers simple operation for recovery and the recycling test showed that it could be reused for successive runs without significant degradation in catalytic activity. [ABSTRACT FROM AUTHOR]

The Heck reaction of aryl halides with terminal olefins was successfully performed by using Pd (OAc)2 as the catalyst in a ligand-free PEG1000-DIL (PEG1000-based dicationic ionic liquid)/toluene system exhibiting temperature-dependent biphasic behavior. In addition, the isolation of the products is readily performed by a simply decantation, and the catalytic system can be recycled and reused without loss of catalytic activity. [ABSTRACT FROM AUTHOR]

A range of multifunctional magnetic metal–organic framework nanomaterials consisting of various mass ratios of the metal–organic framework MIL-53(Fe) and magnetic SiO2 @NiFe2 O4 nanoparticles were designed, prepared, characterized, and evaluated as heterogeneous catalysts for the Knoevenagel condensation. The as-fabricated nanomaterials, especially the nanocatalyst MIL-53(Fe)@SiO2 @NiFe2 O4 (1.0), showed good catalytic performance in the Knoevenagel condensation at room temperature as a result of synergistic interaction between the Lewis acid iron sites of MIL-53(Fe) and the active sites of the magnetic SiO2 @NiFe2 O4 nanoparticles. In addition, the heterogeneous catalyst was readily recovered and a recycling test showed that it could be reused for five times without significant loss of its catalytic activity, making it economical and environmentally friendly. [ABSTRACT FROM AUTHOR]

Mesoporous material supported functionalized ionic liquids have been designed and synthesized, characterized and evaluated as novel heterogeneous catalysts for the Hantzsch reaction. The as‐fabricated catalysts show good performance in the Hantzsch synthesis of 1,4‐dihydropyridines under ambient conditions, especially the titanium incorporated mesoporous material supported ionic liquid Ti‐SBA‐15@IL‐BF4, based on a synergetic effect of titanium site of mesoporous material carrier and the acidic sites of ionic liquid. In addition, the heterogeneous catalyst offers simple operation for recovery and the recycling test showed that it could be reused for five times without significant loss of catalytic activity. Mesoporous material supported functionalized ionic liquids have been designed and synthesized, and evaluated as heterogeneous catalysts for the Hantzsch reaction. Research shows that Ti‐SBA‐15@IL‐BF4 show the best catalytic performance under ambient conditions. The catalyst offers simple operation for recovery and the recycling test showed that it could be reused for five runs without significant loss of catalytic activity, thus making this method economical and environment‐friendly. [ABSTRACT FROM AUTHOR]

Novel periodic mesoporous organosilica supported nanocatalysts with different loading levels of a bis(trifluoromethylsulfonyl)imide anion-based dual imidazolium ionic liquid have been prepared and evaluated as efficient catalysts for the cycloaddition of CO2 to epoxides. The as-fabricated PMO@IL-NTf2(1.0) exhibited the best catalytic performance with excellent conversions (98–100%) and yields (96–99%) at 90 °C and 0.6 MPa for 0.5–1 h, based on a synergistic effect between the dual nucleophilic anion sites of the imidazolium ionic liquid and the hydroxyl group sites of periodic mesoporous organosilica. The excellent recyclability and operational simplicity make this protocol economic and environment-friendly. [ABSTRACT FROM AUTHOR]

A series of MCM-41 supported functionalized ionic liquids doped with copper species were prepared, characterized and evaluated as catalysts in the Biginelli reaction. Most of these supported ionic liquids perform well in the reaction, especially the multifunctional copper coordinated MCM-41 supported heterogeneous catalysts (0.5)IL-TiCl 5 @MCM-41@Cu(15) and (0.5)IL-HSO 4 @MCM-41@Cu(15). The catalytic tests revealed that (0.5)IL-HSO 4 @MCM-41@Cu(15) was the best and powerful catalyst in the Biginelli reaction for the preparation of 3,4-dihydropyrimidinones with high to excellent yields. The catalyst can be easily separated from the reaction mixture by filtration and reused in six consecutive cycles without significant loss in catalytic activity. [ABSTRACT FROM AUTHOR]

Novel mesoporous silica supported ILs have been prepared and successfully applied as a heterogeneous catalyst in Mannich reactions. The excellent recyclability of the supported catalyst, mild reaction conditions, good to excellent yields, low catalyst loading, and operational simplicity are the important features of this methodology. [ABSTRACT FROM AUTHOR]

Compared to N, O and P as directing functional atoms, the application of directing group containing sulfur atoms for transition metal-catalyzed C-H activation is much more difficult for the known reason (some metal catalysts are easily poisoned by sulfur). Here, the disulfide-directed C-H activation for thew synthesis of sulfonyl diphenyl sulfides was realized for the first time by a copper-catalyzed, tandem, one-step C-S coupling/hydroxylation of disulfides and arylboronic acids with oxygen as the oxidant. This method provides a mild and easy method for the synthesis of sulfonyl diphenyl sulfides and 2-(phenylthio)phenol derivatives and avoids producing sulfoxides and sulfones under air conditions and elevated temperatures. [ABSTRACT FROM AUTHOR]

A concise, efficient method to sulfonyl quinones and sulfonyl-1,4-diols through Ir-catalyzed C-S coupling of quinones with sulfonyl chloride has been developed. Thus, this methodology proves its value as a versatile synthetic tool for a broad range of sulfonyl quinones, producing good to excellent yields. Graphical Abstract: [ABSTRACT FROM AUTHOR]

Abstract: The use of single chemotherapeutic drug has shown some limitations in anti-tumor treatment, such as development of drug resistance, high toxicity and limited regime of clinical uses. The combination of two or more therapeutic drugs is feasible means to overcome the limitations. Co-delivery strategy has been proposed to minimize the amount of each drug and to achieve the synergistic effect for cancer therapies. Attempts have been made to deliver chemotherapeutic drugs simultaneously using drug carriers, such as micelles, liposomes, and inorganic nanoparticles (NPs). Here we reported core-shell NPs that were doubly emulsified from an amphiphilic copolymer methoxy poly(ethylene glycol)-poly(lactide-co-glycolide) (mPEG-PLGA). These NPs offered advantages over other nanocarriers, as they were easy to fabricate by improved double emulsion method, biocompatible, and showed high loading efficacy. More importantly, these NPs could co-deliver hydrophilic doxorubicin (DOX) and hydrophobic paclitaxel (TAX). The drug-loaded NPs possessed a better polydispersity, indicating that they are more readily subject to controlled size distribution. Studies on drug release and cellular uptake of the co-delivery system demonstrated that both drugs were effectively taken up by the cells and released simultaneously. Furthermore, the co-delivery nanocarrier suppressed tumor cells growth more efficiently than the delivery of either DOX or TAX at the same concentrations, indicating a synergistic effect. Moreover, the NPs loading drugs with a DOX/TAX concentration ratio of 2:1 showed the highest anti-tumor activity to three different types of tumor cells. This nanocarrier might have important potential in clinical implications for co-delivery of multiple anti-tumor drugs with different properties. [Copyright &y& Elsevier]

Serum opacity factor (SOF). a virulence determinant of Streptococcus pyogenes, converts plasma high-density lipoproteins (HDL) to three distinct species; lipid-free apolipoprotein (apo) A-I, neo HDL, a small discoidal HDL-like particle, and a large cholesteryl ester-rich microemulsion (CERM) that contains the cholesterol esters (CE) of up to ∼400000 HDL particles and apo E as its major protein. Similar SOF reaction products are obtained with HDL, total plasma lipoproteins, and whole plasma. We hypothesized that hepatic uptake of CERM-CE via multiple apo E-dependent receptors would be faster than that of HDL-CE. We tested our hypothesis using human hepatoma cells and lipoprotein receptor-specific Chinese hamster ovary (CHO) cells. The uptake of[3H]CE by HepG2 and Huh7 cells from HDL after SOF treatment, which transfers > 90% of HDL-CE to CERM, was 2.4 and 4.5 times faster, respectively, than from control HDL. CERM-[3H]CE uptake was inhibited by LDL and HDL, suggestive of uptake by both the LDL receptor (LDL-R) and scavenger receptor class B type I (SR-BI). Studies in CHO cells specifically expressing LDL-R and SR-BI confirmed CERM-[3H]CE uptake by both receptors. RAP and heparin inhibit CERM-[3H]CE but not HDL-[3H]CE uptake, thereby implicating LRP-1 and cell surface proteoglycans in this process. These data demonstrate that SOF treatment of HDL increases the rate of CE uptake via multiple hepatic apo E receptors. In so doing, SOF might increase the level of hepatic disposal of plasma cholesterol in a way that is therapeutically useful. [ABSTRACT FROM AUTHOR]

Abstract: Separation and determination of dopamine and epinephrine with end-channel electrochemical (EC) detection integrated on a native printed microchip capillary electrophoresis (CE) system was investigated. Factors influencing the separation and detection were investigated and optimized. Results show manipulating EOF, which can be easily achieved by adjusting buffer pH, is a simple and effective way to achieve the baseline separation of dopamine and epinephrine in native polymeric microchips. Without surface modification of microchannel, printed microchips with advantages of low cost and easy preparation can achieve high performance like other microfluidic devices. [Copyright &y& Elsevier]

The distribution of apolipoprotein (apo) A-I between human high-density lipoproteins (HDL) and water is an important component of reverse cholesterol transport and the atheroprotective effects of HDL. Chaotropic perturbation (CP) with guanidinium chloride (Gdm-Cl) reveals HDL instability by inducing the unfolding and transfer of apo A-I but not apo A-II into the aqueous phase while forming larger apo A-I deficient HDL-like particles and small amounts of cholesteryl ester-rich microemulsions (CERMs). Our kinetic and hydrodynamic studies of the CP of HDL species separated according to size and density show that (l) CP mediated an increase in HDL size, which involves quasi-fusion of surface and core lipids, and release of lipid-free apo A-I (these processes correlate linearly), (2) >94% of the HDL lipids remain with an apo A-I deficient particle, (3) apo A-II remains associated with a very stable HDL-like particle even at high levels of Gdm-Cl, and (4) apo A-I unfolding and transfer from HDL to water vary among HDL subfractions with the larger and more buoyant species exhibiting greater stability. Our data indicate that apo A-I's on small HDL (HDL-S) are highly dynamic and, relative to apo A-I on the larger more mature HDL, partition more readily into the aqueous phase, where, they initiate the formation of new HDL species. Our data suggest that the greater instability of HDL-S generates free apo A-I and an apo A-I deficient HDL-S that readily fuses with the more stable HDL-L. Thus, the presence of HDL-L drives the CP remodeling of HDL to an equilibrium with even larger HDL-L and more lipid-free apo A-I than with either HDL-L or HDL-S alone. Moreover, according to dilution studies of HDL in 3 M Gdm-Cl, CP of HDL fits a model of apo A-I partitioning between HDL phospholipids and water that is controlled by the principal of opposing forces. These findings suggest that the size and relative amount of HDL lipid determine the HDL stability and the fraction of apo A-I that partitions into the aqueous phase where it is destined for interaction with ABCA1 transporters, thereby initiating reverse cholesterol transport or, alternatively, renal clearance. [ABSTRACT FROM AUTHOR]