Task Specific Onium Salts and Ionic Liquids as Soluble Supports in Grieco ’s Multicomponent Synthesis of Tetrahydroquinolines

In this work was presented an application of the use of task specific onium salts (TSOSs) as soluble supports in Grieco’s multicomponent synthesis of tetrahydroquinolines. These soluble supports are of wide applicability and combine advantages of solid phase synthesis without its limitations with those of solution phase chemistry. After a simple washing step, products were cleaved from the supports and obtained in pure form and good yields.     

Interferences by transition metals and their elimination by cyanide as a complexing agent in the determination of arsenic using continuous flow HG-ICP-AES

The interfering effects of various foreign ions on the determination of arsenic were studied by hydride generation inductively coupled plasma atomic emission spectrometry (HG-ICP-AES). There were serious inhibiting interferences by Cu, Pb, Co, Au, Pd and Ni. However, by using cyanide as a complexing agent these interferences could be completely eliminated over a wide range of interferent concentration. The optimum chemical parameters for continuous arsine generation were studied. A major advantage of this technique is that it only needs low acid concentrations and produces less hazardous waste. Sensivity, selectivity and accuracy of the determination of arsenic by HG-ICP-AES were investigated. The detection limit (in 1 mol/l HCl medium) for arsenic(III) was 0.82 ng/ml. The relative standard deviation for ten determinations of a solution containing 50 ng/ml arsenic was 1.3%.     

Synthesis of enantiopure β-amino amides via a practical reductive amination of the corresponding β-keto amides

A convenient and efficient reductive amination for the preparation of chiral β-amino amides is developed utilizing microwave heating. A variety of chiral β-keto amides react with ammonium acetate and sodium cyanoborohydride to afford the desired functionalized amines in good yields. This improved procedure takes advantage of microwave heating to significantly accelerate the reaction and offers a convenient and effective method to access some interesting molecules containing primary amine functionalities.     

New series of acridines and phenanthrolines: synthesis and characterization

New series of acridines and phenanthrolines have been prepared from β-chlorovinyl aldehydes and various aniline derivatives allowing the installation of valuable substituents, such as ketone, nitro or amino groups at the heterocyclic core. X-ray analyses confirmed the structures of acridines and phenanthrolines as well as the presence of partially hydrogenated rings and their crucial impact on the overall shape of the acridine-based architectures. ¹H NMR revealed the helical behaviour of several acridine motives. Comparison of UV data between architectures and influence of number of partially hydrogenated rings is also described.     

Dual Amperometric Immunosensor for Improving Cancer Metastasis Detection by the Simultaneous Determination of Extracellular and Soluble Circulating Fraction of Emerging Metastatic Biomarkers

This paper reports the development of a dual immunosensor using magnetic microcarriers (MBs) and amperometric transduction at dual screen‐printed carbon electrodes (SPdCEs) for the simultaneous determination of two biomarkers: interleukin‐13 receptor α2 (IL‐13Rα2) and E‐cadherin (E‐CDH), with both extracellular and soluble fraction; oncogenic and tumor suppressor markers, respectively, of great relevance in metastatic processes. The implemented methodology involved the formation of sandwich‐type immunocomplexes using specific capture antibodies immobilized onto carboxylic acid magnetic microbeads (HOOC‐MBs), and biotinylated detector antibodies labeled with streptavidin?horseradish peroxidase conjugates (Strep‐HRP). The amperometric detection was performed by addition of hydrogen peroxide in the presence of hydroquinone (HQ) as the redox mediator. The dual immunosensing platform provided linear calibration ranges suitable for the determination of both biomarkers in liquid and solid clinical specimens as well as excellent selectivity against other cancer biomarkers. This simple handling dual bioplatform was applied to the determination of the soluble and extracellular fraction of the target biomarkers in serum and paraffined‐embedded tissues from colorectal cancer (CRC) patients diagnosed at different tumor grade. The obtained results reveal great potential of this configuration to improve the reliability in diagnosing metastatic CRC.     

Opérateur de Monge-Ampère et Tranchage des Courants Positifs Fermés

Sans résumé

---

     

Enhancing <Emphasis Type="SmallCaps">l</Emphasis>-Lysine Production of Beet Molasses by Engineered <Emphasis Type="Italic">Escherichia coli</Emphasis> Using an In Situ Pretreatment Method

Reducing the viscosity of molasses environmentally and selectively removing the harmful ingredients for microbes are the keys to promoting the bioavailability of molasses. A simple and environmental in situ pretreatment method integrating surfactants and alkali was developed to reduce the viscosity of molasses prior to l-lysine production using Escherichia coli ZY0217. Adding activated carbon and modified orange peel based on the in situ pretreatment process effectively removed pigments and excessive zinc in the molasses and also significantly increased the cell growth and l-lysine yield from E. coli ZY0217. The experimental results showed that a mixture of secondary alkane sulfonate, an anionic surfactant, and HodagCB-6, a non-ionic surfactant, effectively reduced the viscosity of the molasses more so than any single surfactant. When the surfactant mixture was added at a concentration of 0.04 g/L to the molasses, the ω value was 0.4, and when ammonia was added at 0.6 %, the lowest viscosity of 705 mPa?·?s was obtained. Further, 91.5 % of the color and 86.68 % of the original levels of zinc were removed using an activated carbon and modified orange peel treatment on the molasses with the lowest viscosity, which further promoted cell growth and l-lysine production. In the fed-batch cultivation process, the l-lysine concentration achieved using a constant-speed feeding strategy was 45.89 g/L, with an l-lysine yield of 27.18 %, whereas the l-lysine yield from untreated molasses was only 10.13 %. The increase in l-lysine yield was related to the reduced viscosity and the detoxification of the molasses. Lastly, the pretreatment was found to significantly enhance the conversion of sugars in the molasses to l-lysine.     

Electrochemical Capacitive K+ EMIS Chemical Sensor Based on the Dibromoaza[7]helicene as an Ionophore for Potassium Ions Detection

A K⁺‐sensitive capacitive electrolyte‐membrane‐insulator‐semiconductor (EMIS) based on a novel dibromoaza[7]helicene ionophore has been developed. An ion‐sensitive membrane based on polyvinylchloride (PVC) doped with the ionophore was deposited on the Si₃N₄/SiO₂/Si‐p/Cu‐Al transducer. The properties of the K⁺‐EMIS chemical sensor were investigated by electrochemical impedance spectroscopy (EIS). All the developed devices upon being tested have shown good sensitivity and linearity responses within the range 10^?6 M to 10^?1 M of potassium activity, with good selectivity over a wide variety of other cations (Na⁺, Li⁺, Cu²⁺, Ca²⁺, and Mg²⁺). To our knowledge, this is the first time that a capacitive field‐effect sensor has been fabricated using helicene as a carrier for K⁺‐detection, combined with the structure: Si₃N₄/SiO₂/Si‐p/Cu‐Al as a transducer.     

Fast and accurate algorithm for cavities reconstruction in an elasticity problem

The aim of this work is to reconstruct the location and geometry of a cavity embedded in a linear isotropic material Ω via an exterior boundary measurement of the displacement field. The considered problem is governed by the linear elasticity system. This inverse problem of geometry reconstruction (ie, location and shape) is formulated as a topology optimization one and solved by minimizing a Kohn‐Vogelius type functional with the help of the topological sensitivity method. Some numerical results are presented using a noniterative geometric algorithm.