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A potential new family of adaptable, ecologically acceptable solvent systems are ionic liquids (ILs). This study is the first to offer a new method for using imidazolium-based ILs as affordable, anti-corrosion electrolytes for activated carbon-based electrochemical capacitors (ECs). In this context, the ILs 1-hexyl 3-methylimidazolium bromide ([HMIM]Br) and 1-ethyl 3-methylimidazolium ethyl sulfate ([EMIM]ES) were synthesized. In the region of ambient temperature up to 105 °C, significant features including viscosity, electrical conductivity, and electrochemical tests were investigated. The symmetric ECs in imidazolium-based electrolytes, which display exceptional electrochemical stability at a maximum voltage of up to 3.5 V, deliver high energy. At room temperature, the specific capacitance of the electrolyte containing IL [HMIM]Br drops to 87 F g−1 (with an energy density of 37 Wh kg−1) from 174 F g−1 (with an energy density of 74 Wh kg−1) under 105 °C. In addition, the supercapacitor made using IL [HMIM]Br retained 90.6% of its capacity up to 10,000 cycles at 105 °C. The findings have significant ramifications for extending the use of eco-friendly, non-toxic, and affordable electrolytes for high-performance ECs with broad voltage windows and improved longevity. [ABSTRACT FROM AUTHOR]

In this research, a novel Brønsted-acidic ionic liquid 1,3-(4,4′-bipyridinium disulfonic acid)-propane-dihydrogen sulfate (BPDSPDH) was synthesized as a bi-functional catalyst. BPDSPDH was characterized using various analytical techniques such as FTIR, TGA, 13CNMR, 1HNMR, and mass spectrometry. Afterward, the catalytic ability of BPDSPDH was explored in the synthesis of chromeno[4,3-b]chromene and pyrido[2,3-d:6,5-d′]dipyrimidine derivatives. BPDSPDH is an ionic liquid catalyst with advantages such as having a high catalytic activity due to its acidic and basic sites, the use of affordable and easily accessible starting materials for catalyst production, recyclability of the catalyst up to 4 times without significant loss in catalytic activity, short reaction time, high yields and moderate reaction conditions. [ABSTRACT FROM AUTHOR]

The fundamental physical properties including density, viscosity and refractive index have been measured for binary mixtures of four fatty acid ethyl esters mixed with diethyl carbonate (DEC) over the entire composition range at temperatures T = (293.15 to 323.15) K and normal atmospheric pressure. The values of excess molar volume, viscosity deviation and refractive index deviation are calculated and the effects of temperature and composition on the variation of excess properties are discussed. All of the values of excess molar volume and refractive index deviation are observed to be positive and the values of viscosity deviation are negative. The excess or deviation properties have also been evaluated and fitted to the Redlich–Kister equation with satisfied results. [ABSTRACT FROM AUTHOR]

This study presents the results from the measurements and further analysis of densities and viscosities of pure 1-ethyl-3-methylimidazolium ethyl sulfate, EMISE, and its binary mixtures with ethylene glycol, EG, over the entire composition range. Measured at atmospheric pressure from 293.15 to 343.15 K. A first-order polynomial equation was fitted to experimental density values of the EMISE + EG binary mixtures, whereas Vogel-Fulcher-Tammann (VFT) equation was used to fit viscosity data. Volumetric and excess properties have been determined. The excess molar volumes and viscosity deviations were correlated by the Redlich–Kister polynomial equation. Additionally, several selected semi-empirical viscosity models for EMISE + EG binary mixtures were tested, and coefficients were obtained. The thermal expansion coefficients of EMISE + EG binary mixtures were calculated. The intermolecular interactions between components were discussed. The results showed that in addition to the intermolecular interactions between components, packing effects due to the molecular size caused changes in properties. [ABSTRACT FROM AUTHOR]

Introducing ionic liquids (ILs) into ultra-high molecular polyethylene (UHMWPE) is a promising approach to improving the processibility of UHMWPE. To have a comprehensive understanding of the role of ILs in affecting the properties and molecular structures of UHWMPE, we conducted a systematic study on the viscoelastic behaviours of UHMWPE/IL composites with various ILs content at room temperature. Stress relaxation tests were performed under constant tensile strain ( ε 0 = 0.47%). Constant strain-rate tests were also performed at five strain rates over the range of 2 × 10–3 s−1 to 1.7 × 10–1 s−1. To have deeper insights into the phenomena and the structure–property relationship, theoretical modelling based on the generalized Maxwell model was employed to study the time-dependent relaxation modulus. The modelling results suggest decreased elasticity and viscosity by the addition of ILs, indicating weakened bonding and enhanced motions of chain segments. Moreover, experimental yield stresses from the constant strain-rate tests were modelled by the cooperative model, which is based on the Eyring's activation theory and takes the cooperative motion of chain segments into accounts. Analysis of the modelling results also shows that ILs increased the effective volume and decreased the energy barrier required to activate chain motions, confirming the enhanced mobilities of chain segments of UHMWPE by the addition of ILs. [ABSTRACT FROM AUTHOR]

Natural products are well established as an important resource and play an important role in drug discovery. Here, two pyrrolinone-fused benzoazepine alkaloids, (+)-asperazepanones A (1) and B (2) with a 6/7/5 ring system, together with the artifact (−)-asperazepanone A (1), were isolated from the coral-derived Aspergillus candidus fungus. Their structures including absolute configurations were elucidated by extensive spectroscopic methods, single crystal X-ray diffraction, and ECD calculations. Furthermore, total syntheses of (±)-1 and (±)-2 have been achieved starting from the commercially L-aspartic acid diethyl ester hydrochloride and monoethyl malonate in 7 and 8 steps, respectively. The key step in the syntheses was an intramolecular Friedel-Crafts reaction to build the unique tricyclic skeleton. Interestingly, (+)-2 not only showed obviously inhibitory activity against NO production, but also inhibited potent LPS-induced expression of TNF-α and IL-6 at the concentration of 0.1 μM. It thus represents a potentially promising lead for anti-inflammatory drug discovery. Benzoazepine is a well-known pharmacophore presented in several marketed drugs. Here, the authors report the isolation and total syntheses of asperazepanones A and B from coral-derived Aspergillus candidus, two novel pyrrolinone-fused benzoazepine alkaloids with potent anti-inflammatory activities. [ABSTRACT FROM AUTHOR]

Diethyl sulphate-based mutagenesis was performed on fungal strain Tolypocladium inflatum MTCC-3538. Two mutant morphotypes MT1-3538 and MT2-3538 were selected for further chemo-profiling studies. LCMS/MS profiling of fungal crude extract confirmed that the wild-type and mutant strains (MT1-3538, MT2-3538) were competent to produce cyclosporine A. MT2-3538 produced 2.1 fold higher cyclosporine A in comparison to the wild type. Further, LCMS-based high throughput media optimization was performed for MT2-3538 in 20 different media combinations to increase cyclosporine A yield. On the basis of ion-intensity profiling, media combination consisting of Glucose 0.1 g/L; Peptone 0.005 g/L and Valine 0.005 g/L was selected and used for up-scaling purpose. Mutant MT2-3538 with optimized media combination increased cyclosporine yield 16 fold and could potentially be exploited for commercial outcomes. [ABSTRACT FROM AUTHOR]

Arylamine N-acetyltransferase 1 (NAT1) plays a pivotal role in the metabolism of carcinogens and is a drug target for cancer prevention and/or treatment. A protein–ligand virtual screening of 2 million chemicals was ranked for predicted binding affinity towards the inhibition of human NAT1. Sixty of the five hundred top-ranked compounds were tested experimentally for inhibition of recombinant human NAT1 and N-acetyltransferase 2 (NAT2). The most promising compound 9,10-dihydro-9,10-dioxo-1,2-anthracenediyl diethyl ester (compound 10) was found to be a potent and selective NAT1 inhibitor with an in vitro IC50 of 0.75 µM. Two structural analogs of this compound were selective but less potent for inhibition of NAT1 whereas a third structural analog 1,2-dihydroxyanthraquinone (a compound 10 hydrolysis product also known as Alizarin) showed comparable potency and efficacy for human NAT1 inhibition. Compound 10 inhibited N-acetylation of the arylamine carcinogen 4-aminobiphenyl (ABP) both in vitro and in DNA repair-deficient Chinese hamster ovary (CHO) cells in situ stably expressing human NAT1 and CYP1A1. Compound 10 and Alizarin effectively inhibited NAT1 in cryopreserved human hepatocytes whereas inhibition of NAT2 was not observed. Compound 10 caused concentration-dependent reductions in DNA adduct formation and DNA double-strand breaks following metabolism of aromatic amine carcinogens beta-naphthylamine and/or ABP in CHO cells. Compound 10 inhibited proliferation and invasion in human breast cancer cells and showed selectivity towards tumorigenic versus non-tumorigenic cells. In conclusion, our study identifies potent, selective, and efficacious inhibitors of human NAT1. Alizarin's ability to inhibit NAT1 could reduce breast cancer metastasis particularly to bone. [ABSTRACT FROM AUTHOR]

The effect of controlled deactivation of Ni/SiO2 catalysts in the reactions of liquid-phase reduction of the carbon–carbon double bond in maleic acid diethyl ester (MADE) molecule was examined. The influence of the total quantity of deposited metal and of the quantity of reduced metal on the structural and mechanical, as well as the catalytic properties of nickel deposited on silica gel was studied. The effect produced by the surface sulfidation on the catalytic properties of the active metal as dependent on the percentage of the nickel oxide deposited was demonstrated. Practical absence of the relative structure sensitivity of the supported catalysts was experimentally proved. The relative structure sensitivity of the catalyst was calculated as the fractal dimension of the surface of the Ni°/SiO2 samples after one of the technological processes, related to that of the fresh nickel catalyst. The relative structure sensitivity of the catalyst surface as influenced by various hydrodynamic regimes, increased pressure, and nature of the solvent, as well as by adsorption of the reactants and the proceeding of the hydrogenation reactions and the deactivation process was considered. It was found that, during the synthesis process, the catalyst was saturated with hydrogen in the reactor, the reduction reaction of MADE proceeded, the catalyst was deactivation by the sulfide ion, and the catalyst surface underwent certain changes. Specifically, the surface roughness increased, and the sizes of the agglomerates and of the crystallites decreased. The influence of controlled partial deactivation of the nickel active sites by the sulfide ion on the activity of the supported catalysts was evaluated, and the ratios of the surface atoms of nickel, hydrogen, and sulfur in the catalytic systems possessing different activities were calculated. It was shown that, when the nickel catalyst surface was deactivated by the sulfide ions taken in a proportion of one sulfur atom per two surface nickel atoms, the activity of the catalyst was reduced by 90% and could not be subsequently restored. [ABSTRACT FROM AUTHOR]

A series of new substituted phosphonylated 1,3-oxazoles, 2-aryl-4-[1,2-bis(dialkoxyphosphoryl)vinyl]-5-ethoxy-1,3-oxazoles, was obtained by the reaction of ethynyldiphosphonic acid tetramethyl ester with diethyl 2-aroylaminomalonates. The reaction proceeds stereoselectively with the intermediate formation of the corresponding Z-2-aroylamino-2-[1,2-bis(dialkoxyphosphoryl)vinyl]malonates. [ABSTRACT FROM AUTHOR]

Alcohol consumption during pregnancy constitutes one of the leading preventable causes of birth defects and neurodevelopmental disorders in the exposed children. Fatty acid ethyl esters (FAEEs), ethyl glucuronide (EtG) and ethyl sulfate (EtS) have been studied as potential biomarkers of alcohol consumption. However, most analytical approaches proposed for their analysis in meconium samples consist of separated extraction procedures requiring the use of two meconium aliquots, which is costly in terms of both time and materials. Therefore, the aim of this study was to develop and validate a method for the simultaneous extraction of 9 FAEEs, EtG and EtS from one meconium aliquot. The sample was homogenized using methanol, and then FAEEs were extracted with hexane while EtG and EtS were isolated using acetonitrile. Then, extracts were applied to solid-phase extraction columns and analysed by gas chromatography mass spectrometry (FAEEs) and liquid chromatography tandem mass spectrometry (EtG and EtS). Calibration curves were linear with r values greater than 0.99. The LODs ranged from 0.8 to 7.5 ng/g for FAEEs and were 0.2 ng/g and 0.8 ng/g for EtS and EtG, respectively. LOQs ranged from 5 to 25 ng/g for FAEEs and were 1 ng/g and 2.5 ng/g for EtS and EtG, respectively. Accuracies and precisions were between 93.8 and 107% and between 3.5 and 9.7%, respectively. The recovery values ranged from 89.1 to 109%. The method proved to be sensitive, specific, simple and fast and allowed for the reduction of the amount of organic solvent used for extraction compared to other published data while higher recoveries were obtained. The method was used for analysis of meconium samples in two cases of mothers who were consuming alcohol during pregnancy. [ABSTRACT FROM AUTHOR]

[2-Aryl-4-hydroxy-1-(5-methylisoxazol-3-yl)-5-oxo-2,5-dihydro-1H-pyrrol-3-yl]acetic acids and their esters were synthesized by the three-component reaction of α-ketoglutaric acid or its diethyl ester with 3-amino-5-methylisoxazole and aromatic aldehydes. [ABSTRACT FROM AUTHOR]

Aseries of diethyl esters of 2-aryl-4-hydroxy-4-methyl-6-oxocyclohexane-1,3-dicarboxylic acids (β-cycloketols) were synthesized by Knoevenagel condensation. A method for their dehydration was developed. Peculiarities of the condensation depending on the reaction conditions were pointed out. All obtained cycloketols and some dehydrated analogs exhibited more or less pronounced anticonvulsant activity in the corazole seizure test in mice. [ABSTRACT FROM AUTHOR]

A room temperature benzene and formaldehyde gas sensor system with an ionogel as sensing material is presented. The sensing layer is fabricated employing poly(N-isopropylacrylamide) polymerized in the presence of 1-ethyl-3-methylimidazolium ethyl sulfate ionic liquid onto gold interdigitated electrodes. When the ionogel is exposed to increasing formaldehyde concentrations employing N2 as a carrier gas, a more stable response is observed in comparison to the bare ionic liquid, but no difference in sensitivity occurs. On the other hand, when air is used as carrier gas the sensitivity of the system towards formaldehyde is decreased by one order of magnitude. At room temperature, the proposed sensor exhibited in air higher sensitivities to benzene, at concentrations ranging between 4 and 20 ppm resulting, in a limit of detection of 47 ppb, which is below the standard permitted concentrations. The selectivity of the IL towards HCHO and C6H6 is demonstrated by the absence of response when another IL is employed. Humidity from the ambient air slightly affects the resistance of the system proving the protective role of the polymeric matrix. Furthermore, the gas sensor system showed fast response/recovery times considering the thickness of the material, suggesting that ionogel materials can be used as novel and highly efficient volatile organic compounds sensors operating at room temperature. Graphical abstract [ABSTRACT FROM AUTHOR]

Accurate determination of a person's blood alcohol concentration (BAC) is an important task in forensic toxicology laboratories because of the existence of statutory limits for driving a motor vehicle and workplace alcohol testing regulations. However, making a correct interpretation of the BAC determined in postmortem (PM) specimens is complicated, owing to the possibility that ethanol was produced in the body after death by the action of various micro-organisms (e.g., Candida species) and fermentation processes. This article reviews various ways to establish the source of ethanol in PM blood, including collection and analysis of alternative specimens (e.g., bile, vitreous humor (VH), and bladder urine), the identification of non-oxidative metabolites of ethanol, ethyl glucuronide (EtG) and ethyl sulfate (EtS), the urinary metabolites of serotonin (5-HTOL/5-HIAA), and identification of n-propanol and n-butanol in blood, which are known putrefaction products. Practical utility of the various biomarkers including specificity and stability is discussed. [ABSTRACT FROM AUTHOR]

TLC analysis of Knautia arvensis demonstrated phenolcarboxylic acids and flavonoids. Spectrophotometric studies were run to assess the quantitative composition of phenolic compounds expressed as chlorogenic acid (from 1.05% to 2.08%), and it was proposed that this substance can be used for standardization of samples of Knautia arvensis herb. HPLC-UV identified the presence of o-coumaric, gallic, neochlorogenic, chlorogenic, caffeic, isoferulic, and rosmarinic acids, as well as hyperoside and kaempferol. Chlorogenic acid was present in the greatest quantity (0.29 – 0.60%). GLC-MS showed that hexane extracts contained 92 substances, including a-linoleic acid, ethyl esters of palmitic, palmitoleic, 13-methyltetradecanoic, and phenylacetic acids, phytol, diethylacetal isovaleraldehyde, hexahydrofarnesyl acetone, diethoxyethane, 14-methyl-8-hexadecenal, succinic acid diethyl ester, dihydrocitronellol, phenylacetaldehyde, and others. [ABSTRACT FROM AUTHOR]

Increased alcohol consumption, especially among young people, is a major concern in Turkey as it is around the world due to negative effects on public health and safety. Regarding this, it is pivotal to monitor and therefore control alcohol use in public. In this case, wastewater-based epidemiology (WBE), which is the in-depth analysis of wastewater and a relatively new method, can deliver complementary information concerning the abuse of different substances. The proven potential of the WBE approach offers new promises in the process of monitoring alcohol use, namely the monitoring of the levels of ethyl sulfate (EtS) as a urinary biomarker of alcohol consumption, and it is a powerful mean to estimate alcohol use at the community level. In this study, raw 24-h composite wastewater samples were collected from Seyhan and Yüregir wastewater treatment plants (WWTPs) in Adana Province for one week per season (October 2016–August 2017). The fast and validated analytical method was performed by liquid chromatography coupled to tandem mass spectrometry (LC-MS/MS) and therefore applied to the analysis of ethyl sulfate (EtS). Obtained concentration values were back-calculated, and regional and temporal social usage rates were determined. Higher values were calculated for both WWTPs on Sunday. Alcohol consumption in the region served by Seyhan WWTP was higher than Yüregir WWTP. The results showed that the levels of alcohol consumption during given periods in Adana ranged from 659.8 to 8998.7 mL/day/1000 per person with an average value of 4983.9 and 3924.2 mL/day/1000 inhabitant in Seyhan WWTP and Yüregir WWTP, respectively. This study shows that weekly and annual trends in alcohol consumption can be detected quickly from wastewater analysis. [ABSTRACT FROM AUTHOR]

Improvement of the production of vincamine in endophytic fungus VINI-7 was performed by using the inactivated protoplast fusion method. The preparation conditions of protoplasts were optimized by systematic trials with various parameters, and inactivated protoplast fusion was subsequently performed. The mycelium in logarithmic growth phase was treated with 1500 U/mL lywallzyme, 1500 U/mL lysozyme, 2000 U/mL cellulase, and 1000 U/mL snailase solution for 3 h at 30 °C and had the best conditions, in which the concentration of the protoplast was 3.17 × 107 cells/mL. Protoplasts were inactivated by heat, ultraviolet, microwave, sodium nitrite, and diethyl sulfate, respectively. Subsequently, protoplasts inactivated by different methods were subjected to respective protoplast fusion. The results showed that the yield of vincamine in fusants inactivated by mutagens was generally higher than that of fusants inactivated by heat. The highest yield of vincamine in two fusants (U-U1 and N-N1) was 31.6 and 38.7 mg, which increased to 162.24 and 221.16%, respectively, as compared to the parent strain (12.05 mg). LC-MS/MS analysis showed that U-U1 and N-N1 fusants could produce vincamine. Furthermore, the results of genetic stability experiments indicated that U-U1 and N-N1 were genetically stable. [ABSTRACT FROM AUTHOR]

Cascade reaction of 2 equiv. of furfural (or equimolar amounts of furfural and aromatic aldehyde) with secondary amines and ethyl cyanoacetate afforded diethyl esters of 8-(dialkylamino)-3-aryl-6-oxo-2,4-dicyanobicyclo[3.2.1]octane-2,4-dicarboxylic acids with yields of 37–54%. Antimicrobial activity of a number of obtained compounds in vitro was studied, and biological activity in silico was analyzed. The obtained bicyclo[3.2.1]octanes are inactive or exhibit weak fungicidal activity, but exhibit moderate bactericidal effect. [ABSTRACT FROM AUTHOR]

The reactions of diaryl-, aryl-, and alkyl–arylcyclopropanes with ethyl nitrite in the presence of sulfur trioxide and sulfur trioxide dioxane complex, as well as the reactions of 1-alkyl-2-arylcyclopropanes with NOBF4 were studied. It was found that the attack of the nitrosonium cation, accompanied by the formation of a benzyl carbocation, leads to the formation of isoxazolines. The introduction of bulky alkyl substituents into the cyclopropane ring changes the regioselectivity of nitrosation, favoring the attack of the electrophilic particle on the benzyl position and leading to the competitive formation of an alkyl carbocation. Depending on the structure of the alkyl substituent, both products of intramolecular heterocyclization accompanied by skeletal rearrangements and products formed with the participation of an external nucleophile are formed. [ABSTRACT FROM AUTHOR]

A series of (2-amino-3-cyano-4H-chromen-4-yl) phosphonic acid diethyl ester derivatives were synthesized from salicylaldehyde, malononitrile and triethylphosphite in ethanol/water (1:1) system using a new dual basic ionic liquid, i.e., 1-[3-(dimethylamino)propyl]-1,4-diazabicyclo[2.2.2]octan-1-ium hydroxide at ambient temperature. The attractive features of this protocol are higher yields (more than 95%), low cost, reduced environmental impact, shorter reaction time, reusability of IL (up to 7 times) and convenience of procedure. The possible bioactivity study was also carried out by using molecular docking study for all the synthesized compounds and molecules can be act as anticancer agent. Synthesis of some new (2-amino-3-cyano-4H-chromen-4-yl) phosphonic acid diethyl ester derivatives by using new dual basic ionic liquid. [ABSTRACT FROM AUTHOR]

Unsymmetrical and symmetrical azomethines were obtained using the condensation reaction of diamino-thiophene-3,4 dicarboxylic acid diethyl ester with 4-(1-pyrrolidino)benzaldehyde, fluorene-2-carboxaldehyde, 1-methylindole-3-carboxaldehyde, and benzothiazole-2-carboxaldehyde. Their thermal, optical, and electrochemical properties were investigated, and the results were supported by calculations using the density functional theory. The studied compounds melted in the range of 170–260 °C and can be converted into amorphous materials with high glass transition temperatures between 76 and 135 °C. They were thermally stable up to 220–300 °C. All imines were electrochemically active and exhibited low energy band gaps below 2 eV (except for one imine with Eg = 2.39 eV) determined on the basis of cyclic voltammetry. Most of the azomethines were emissive in solution and in the solid state. Some of them showed both S1 (first excited state) emission and S2 (second excited state) emission or only fluorescence from higher excited state, which is first time observed for azomethines. The imine with the most promising properties was tested in a light-emitting diode, and its ability for emission of light under external voltage was demonstrated. [ABSTRACT FROM AUTHOR]

A simple and selective method for introducing stable 13C and 15N isotopes into the structure of the sodium salt of 4-oxo-1,4-dihydropyrazolo[5,1-c][1,2,4]triazine-3,8-dicarboxylic acid diethyl ester, a potential antiglycation agent, has been developed. Labeled [1,3-13C2]-malonic ester (99% 13C) was used as the 13C isotope donor. The introduction of the 15N atom was carried out using enriched sodium nitrite (98% 15N). The obtained 13C2 and 15N isotope-labeled analog of a promising antidiabetic compound of the pyrazolo- [5,1-c][1,2,4]triazine series was characterized by NMR spectroscopy and high-resolution mass spectrometry. [ABSTRACT FROM AUTHOR]

3-Methyl-1-butanol (3MB) is a promising biofuel that can be produced from 2-ketoisocaproate via the common l-leucine biosynthesis pathway. Corynebacterium glutamicum was chosen as a host bacterium because of its strong resistance to isobutanol. In the current study, several strategies were designed to overproduce 3MB in C. glutamicum through a non-fermentation pathway. The engineered C. glutamicum mutant was obtained by silencing the pyruvate dehydrogenase gene complex (aceE) and deleting the lactic dehydrogenase gene (ldh), followed by mutagenesis with diethyl sulfate (DES) and selection with Fmoc-3-4-thiazolyl-l-alanine (FTA). The mutant could produce 659 mg/L of 3MB after 12 h of incubation. To facilitate carbon flux to 3MB biosynthesis, the engineered recombinant was also constructed without branched-chain acid aminotransferase (ilvE) activity by deleting the ilvE gene. This recombinant could produce 697 mg/L of 3MB after 12 h of incubation. [ABSTRACT FROM AUTHOR]

A wild-type strain was isolated from slightly rotted pears after three rounds of enrichment culture, identified as Saccharomyces cerevisiae 3308, and evaluated for its fermentation capability of second generation bioethanol and tolerance of temperature, glucose and ethanol. S. cerevisiae 3308 was mutated by using the physical and chemical mutagenesis methods, ultraviolet (UV) and diethyl sulfate (DES), respectively. Positive mutated strains were mainly generated by the treatment of UV, but numerous negative mutations emerged under the treatment of DES. A positive mutated strain, UV-20, produced ethanol from 62.33 ± 1.34 to 122.22 ± 2.80 g/L at 30-45 °C, and had a maximum yield of ethanol at 37 °C. Furthermore, UV-20 produced 121.18 ± 2.51 g/L of second generation bioethanol at 37 °C. Simultaneously, UV-20 exhibited superior tolerance to 50% of glucose and 21% of ethanol. In a conclusion, all of these results indicated that UV-20 has a potential industrial application value. [ABSTRACT FROM AUTHOR]

Tri- and tetrasubstituted tetrahydropyranes fused to one and two heterocycles with various functional groups (COOEt, Br, MeC=CH) were synthesized in stereoselective fashion by reactions of syn- and anti-1-R-2-(4-bromophenyl)-5-methylhex-4-en-1-ols (R = Bu, PhCH) with trifluoromethanesulfonic acid, aldehydes in the presence of boron trifluoride-diethyl ether complex (Prins reaction), and salicylaldehydes in the presence of trimethyl orthoformate and p-toluenesulfonic acid. The obtained compounds were brought into Suzuki coupling with thiofen-2-ylboronic acid, hydrolysis, and reduction of the ester group with lithium tetrahydridoaluminate. The resulting carboxylic acid was converted to carboxamide, and the alcohol was oxidized to aldehyde which was converted to oxime. The steric configuration of substituents remained unchanged in all chemical transformations. [ABSTRACT FROM AUTHOR]

The reactions of chloroethynylphosphonates with aromatic secondary aminomalonates occur as classic nucleophilic substitution of chlorine atom at the sp-hybridizied carbon atom to form new phosphorylated 2-arylaminomalonates, diethyl esters of 2-(diethoxyphosphorylethynyl)-2-arylaminomalonic acids. Nonobservance of chemo- and regioselectivity was revealed when using cyclohexyl- and benzylaminomalonates. [ABSTRACT FROM AUTHOR]

Three-component condensation of N-aryl- and N, N-diethyl-3-oxobutanamides with salicylaldehyde and thiourea in ethanol in the presence of sodium hydrogen sulfate afforded N-aryl- and N, N-diethyl-9-methyl-11-sulfanylidene-8-oxa-10,12-diazatricyclo[7.3.1.0]trideca-2,4,6-triene-13-carboxamides. Reaction of the same compounds in the absence of a catalyst under solvent-free conditions gave N-aryl-6-(2-hydroxyphenyl)-4-methyl-2-sulfanylidene-1,2,3,6-tetrahydropyrimidine-5-carboxamides. [ABSTRACT FROM AUTHOR]

Introduction: Abstinence from ethanol is necessary in various situations. Among these are jail terms. Nevertheless, it is a matter of fact that ethanol is illegally produced and ingested in prisons. So far, data regarding drug prevalence in jail have mainly been collected by questionnaires. To get an objective database for the prevalence of ethanol consumption in jail, a cross-sectional study was performed. Methods: Inmates of two German prisons (Offenburg and Freiburg) were asked to give a urine sample at an unknown and random point of time. Participation was voluntary and did lead to neither negative consequences nor benefits. All samples were anonymized. Using the consumption markers ethyl glucuronide (EtG) and ethyl sulfate (EtS), the urine samples were tested for previous ethanol consumption. Analyses were performed by a validated liquid chromatography-tandem mass spectrometry (LC-MS/MS) method. Results: In total 676 male inmates participated in this study. The participation rate was 70-75 % of all permanent inmates in Offenburg and 30.6 % in Freiburg. Ten of the 555 (1.8 %) samples from Offenburg and 1 of the 121 (0.8 %) samples from Freiburg were positive for ethanol consumption markers with concentrations ranging from trace amounts to 1400 ng/mL for EtG and up to 510 ng/mL for EtS, respectively. Conclusions: The number of participants in this study was rather high, so that the results represent a good cross section, at least for Offenburg, the jail with the higher number of positive samples. [ABSTRACT FROM AUTHOR]

Ethyl sulfate (EtS) is a minor metabolite of ethanol, usually being present along with ethyl glucuronide in both blood and urine. At present, there have been few studies on sulfotransferases (SULTs) catalyzing EtS formation. Moreover, inhibition by nutritional components on EtS formation, e.g., polyphenols that are extensively sulfonated, has not been addressed at all. Firstly, the incubation procedure was optimized with regard to buffer, substrate concentration, and incubation time. Recombinant SULT enzymes including SULT1A1, 1A3, 1B1, 1E1, and 2A1 were screened for their activity towards ethanol; subsequently, respective kinetics was investigated. The inhibitory potential of resveratrol, quercetin, and kaempferol being abundant in beer and wine was studied thereafter. Analysis was performed by liquid chromatography/tandem mass spectrometry (LC-MS/MS) using deuterated EtS as the internal standard. All enzymes are involved in the sulfonation of ethanol; respective kinetics followed the Michaelis-Menten model. Among the five SULTs under investigation, SULT1A1 displayed the highest activity towards ethanol followed by SULT2A1. Polyphenols significantly reduced the formation of EtS. Results revealed multiple SULT isoforms being capable of catalyzing the transfer of a sulfo group to ethanol; nevertheless, the relevance of SULTs' polymorphism on the sulfonation of ethanol needs further appraisal. Nutritional components such as polyphenols effectively inhibit formation of EtS; this observation may partly serve as an explanation of the highly inter-individual variability of EtS findings in both blood and urine. [ABSTRACT FROM AUTHOR]

A new approach to phosphorylation of benzene with diethyl phosphite is suggested, which is based on the electrocatalytic oxidation of a mixture of benzene and diethyl phosphite (1 : 1) under mild conditions (room temperature, normal pressure) in the presence of bimetallic catalytic systems Mn/CoL (MnSO/CoCldmphen or MnCl/CoClbipy). This method gives diethyl phenylphosphonate in high yield (up to 90%) and practically 100% conversion of the phosphite. [ABSTRACT FROM AUTHOR]

Reaction of available derivatives of 1-acylamino-2,2-dichloroacrylic acids as well as diethyl esters of 1-acylamino-2,2,2-trichloroethylphosphonic acids with N-methyl-D-glucamine furnished previously unknown 1,3-oxazole derivatives containing nitrile, ester or phosphonyl groups in the position 4 and N-methyl- D-glucamine residue in the position 5. [ABSTRACT FROM AUTHOR]

Presence of fatty acid ethyl esters (FAEE), ethyl glucuronide (EtG), and ethyl sulfate (EtS) in meconium, the first neonatal feces, identifies maternal alcohol consumption during pregnancy. Current meconium alcohol marker assays require separate analyses for FAEE and EtG/EtS. We describe development and validation of the first quantitative liquid chromatography tandem mass spectrometry assay for 9 FAEEs, EtG, and EtS in 100 mg meconium. For the first time, these alcohol markers are analyzed in the same meconium aliquot, enabling comparison of the efficiency of gestational ethanol exposure detection. 100 mg meconium was homogenized in methanol and centrifuged. The supernatant was divided, and applied to two different solid phase extraction columns for optimized analyte recovery. Limits of quantification for ethyl laurate, myristate, linolenate, palmitoleate, arachidonate, linoleate, palmitate, oleate, and stearate ranged from 25-50 ng/g, with calibration curves to 2,500-5,000 ng/g. EtG and EtS linear dynamic ranges were 5-1,000 and 2.5-500 ng/g, respectively. Mean bias and between-day imprecision were <15 %. Extraction efficiencies were 51.2-96.5 %. Matrix effects ranged from −84.7 to 16.0 %, but were compensated for by matched deuterated internal standards when available. All analytes were stable (within ±20 % change from baseline) in 3 authentic positive specimens, analyzed in triplicate, after 3 freeze/thaw cycles (−20 °C). Authentic EtG and EtS also were stable after 12 h at room temperature and 72 h at 4 °C; some FAEE showed instability under these conditions, although there was large inter-subject variability. This novel method accurately detects multiple alcohol meconium markers and enables comparison of markers for maternal alcohol consumption. [Figure not available: see fulltext.] [ABSTRACT FROM AUTHOR]

In this study, to discuss the importance of the cell cycle distribution in cell-based in vitro toxicity mechanism studies, diethyl sulfate (DES) was selected as a model chemical that induced the alteration of the cell cycle distribution in human bronchial epithelial cell line 16HBE 14o- (HBE) cells. Cells were treated with various concentrations of DES, cell proliferation and apoptosis were then determined. The results showed that DES concentration-dependently inhibited HBE cells proliferation and induced apoptosis. When cells were treated with 2.0 mM of DES for 20 or 28 h, significant S and G2/M phase accumulation was observed. Then, the relative cellular levels of Cdk4, p-Cdk2 (Thr160), Cyclins A and B1 in DES-treated HBE cells at 20 and 28 h were determined by two ways. The differences of the cell cycle distribution between DES and control groups were ignored in one way and eliminated by using flow cytometric cell sorting in the other. The results obtained by the two ways were quite different, which indicated that the cell cycle distribution might result in confounding if it was significantly different between the treated and control groups. Therefore, we propose that the cell cycle distribution should be given more consideration in cell-based in vitro toxicological studies. [ABSTRACT FROM AUTHOR]

Bacillus subtilis mutants were obtained after the wild strain JNA 3-10 was mutagenized by UV irradiation coupled with diethyl sulfate. A visual filter assay was employed for the qualitative identification of 2,3-butanediol dehydrogenase (BDH) blocked B. subtilis. Selected mutants were tested for the activities of acetoin reductase (AR) and BDH. According to further batch fermentation, one mutant named JNA-UD-6 that produced 24.3 % more acetoin than JNA 3-10 with the corresponding byproducts of 2,3-butanediol decreased by 39.8 % was isolated. A nonsense mutation (p.Tyr118X) that precluded the synthesis of a full-length functional AR/BDH within the bdhA gene of JNA-UD-6 was detected. Acetoin production of JNA-UD-6 was further improved to about 53.9 g/L in a 5-L fermentor with 150 g/L glucose consumed. However,a small amount of 2,3-butanediol was found in late phase of JNA-UD-6 fermentation, and it was due to the existence of a putative gene that encoding a minor AR. This work proved a strategy to efficiently breeding an acetoin high producing strain by traditional mutation methods. [ABSTRACT FROM AUTHOR]

Background: Ethyl glucuronide (EtG) and ethyl sulfate (EtS) are non-oxidative minor metabolites of ethanol. They are detectable in various body fluids shortly after initial consumption of ethanol and have a longer detection time frame than the parent compound. They are regarded highly sensitive and specific markers of recent alcohol uptake. This study evaluates the determination of EtG and EtS from dried blood spots (DBS), a simple and cost-effective sampling method that would shorten the time gap between offense and blood sampling and lead to a better reflectance of the actual impairment. Methods: For method validation, EtG and EtS standard and quality control samples were prepared in fresh human heparinized blood and spotted on DBS cards, then extracted and measured by an LC-ESI-MS/MS method. Additionally, 76 heparinized blood samples from traffic offense cases were analyzed for EtG and EtS as whole blood and as DBS specimens. The results from these measurements were then compared by calculating the respective mean values, by a matched-paired t test, by a Wilcoxon test, and by Bland-Altman and Mountain plots. Results and discussion: Calibrations for EtG and EtS in DBS were linear over the studied calibration range. The precision and accuracy of the method met the requirements of the validation guidelines that were employed in the study. The stability of the biomarkers stored as DBS was demonstrated under different storage conditions. The t test showed no significant difference between whole blood and DBS in the determination of EtG and EtS. In addition, the Bland-Altman analysis and Mountain plot confirmed that the concentration differences that were measured in DBS specimens were not relevant. [ABSTRACT FROM AUTHOR]

In this article, electrolytic (ionic) conductivity measurements of four ionic liquids (ILs), namely, 1-ethyl-3-methylimidazolium bis[(trifluoromethyl)sulfonyl] imide ([C $$_{2}$$ mim][NTf $$_{2}$$ ]), 1-ethyl-3-methylimidazolium trifluoromethanesulfonate ([C $$_{2}$$ mim][OTf]), 1-hexyl-3-methylimidazolium bis[(trifluoromethyl)sulfonyl]imide ([C $$_{6}$$ mim][NTf $$_{2}$$ ]), and 1-ethyl-3-methylimidazolium ethyl sulfate ([C $$_{2}$$ mim][EtSO $$_{4}$$ ]) (ECOENG212 $$^\circledR $$ ), were performed in a temperature range of (288.15 to 333.15) K. [C $$_{6}$$ mim][NTf $$_{2}$$ ] was chosen to be a reference ionic liquid for several properties, including the electrolytic conductivity by the IUPAC Project 2002-005-1-100. For that reason, the measurements performed with that ionic liquid primarily serve the purpose to validate the instrumentation and the experimental procedure used in this work. The measurements were carried out using a complex impedance method, applying a novel electronic device designed and constructed for this purpose. The complete setup includes a Schott Instruments LF 913 T, used as a four-electrode conductivity cell, and a lock-in amplifier. The cell was calibrated using standard reference KCl aqueous solutions. The measurements of the impedance of the conductivity cell were carried out along a range of frequencies from (0.2 to 30) kHz, and the results were extrapolated to infinite frequency, in order to determine the electrolytic conductivity of the liquid samples. The results obtained for the ionic liquid [C $$_{6}$$ mim][NTf $$_{2}$$ ] were compared to reference data, and it was estimated that the overall uncertainty of the present results is better than 2 %. All the data obtained were compared with available literature data, and were analyzed and discussed in respect to the effect of temperature, cation alkyl chain length, and anion. [ABSTRACT FROM AUTHOR]

A stable and specific electrochemical biosensor based on a poly(3,4-ethylenedioxythiophene)-ethyl sulfate (PEDOT-EtSO) matrix with high conductivity and stability was easily fabricated. 1-Ethyl-3-methylimidazolium ethyl sulfate ([Emim][EtSO]), a halogen-free and relatively hydrolysis-stable hydrophilic ionic liquid, was selected as the supporting electrolyte for the one-step electrosynthesis of the PEDOT-EtSO matrix under the optimum conditions. The PEDOT-EtSO matrix electrosynthesized in the [Emim][EtSO] aqueous solution displayed high conductivity and stability. Inspired by preceding studies, the electrochemical biosensor based on the resulting PEDOT-EtSO matrix was facilely developed to determine the vitamin C (VC) level in commercial juices. Ascorbate oxidase (AO) was dip-coated on the surface of the as-prepared matrix, then Nafion was covered on the surface of AO layers for preventing the leakage of enzyme molecules. The fabricated biosensor displayed an excellent bioelectrocatalytic activity to the oxidation of VC. Under optimal conditions, the fabricated amperometric biosensor showed rapid response (less than 2 s) to VC at a low potential of 0.2 V over a wide range of concentrations from 8.0 × 10 to 1 × 10 M with a high sensitivity of 104.8 mA M cm, and the limit of detection and the limit of quantification of presented method was 0.147 μM and 0.487 μM, respectively. Moreover, the bioaffinity, specificity, stability, and reproducibility of the biosensor were also evaluated. Finally, the biosensor was employed to determine the content of VC in commercial juice samples by amperometric and voltammetric methods. The satisfactory results indicated that the as-prepared conducting PEDOT-EtSO films as immobilization matrix of biologically active species could be a promising candidate for the design and application of biosensors. [ABSTRACT FROM AUTHOR]

The product of substitution at the nitrogen atom N(4) is found along with main N(1)- and N(2)-substituted 5-R-3-nitro-1,2,4-triazoles among the products of 5-R-nitro-1,2,4-triazolate anion (R = H, Me, Et) reactions with diethyl sulfate in aqueous medium. The fraction of 5-R-4-ethyl-3-nitro-1,2,4-tri-azoles, which varies from 1.3 to 6.9%, depends on the temperature, ratio of the starting reagents, and the degree of the alkylating agent consumption. [ABSTRACT FROM AUTHOR]

Ethyl glucuronide (EtG) and ethyl sulfate (EtS) are commonly used alcohol markers for previous alcohol consumption. Nevertheless, the optimum EtG cutoff for urinary abstinence tests is still being discussed, and no cutoff has been recommended for EtS yet. The aim of this study was to verify cutoffs by investigating EtG and EtS concentrations (c and c) in the urine of healthy persons after drinking small, but realistic amounts of alcohol (one or two glasses of beer or white wine), and to look for the window of detection in strongly alcohol-intoxicated patients who were beginning withdrawal treatment. Very high EtG and EtS concentrations were measured in the first urine samples of patients under withdrawal treatment. However, 24 h later, concentrations decreased considerably, and c < 0.5 mg/l and c < 0.1 mg/l were determined in 26.7 % (4/13) and 13.3 % (2/13) of the samples, respectively. Concentrations above 0.1 mg/l (EtG) and 0.05 mg/l (EtS) were measured for 23.5 and 20.5 h after consuming 0.1 l of white wine or 0.33 l of beer, and 24 h after the experiment, 75 % (9/12) of the urine samples were tested negative for EtG and EtS using the following cutoffs: EtG 0.5 mg/l and EtS 0.1 mg/l. In half of the samples, concentrations below 0.1 mg/l (EtG) and 0.05 mg/l (EtS) were detected. Urinary cutoffs for EtG of 0.5 mg/l or higher are not suitable for testing abstinence. Even 0.1 mg/l is not effective to detect the intake of small amounts of alcohol in the context of abstinence tests. For EtS, 0.05 mg/l were found to be a potential cutoff to exclude the repeated intake of alcohol. Yet, further research is required to verify this cutoff. For a limited time period, EtG and EtS concentrations within the range of these cutoffs are also detectable after unintentional consumption of alcohol. Participants of abstinence programs have to be informed about the alcohol content of certain foods and beverages whose consumption is in conflict with strict abstinence. [ABSTRACT FROM AUTHOR]

Ethyl glucuronide (EtG) and ethyl sulfate (EtS) are direct alcohol consumption markers widely used nowadays for clinical and forensic applications. They are detectable in blood and urine even after consumption of trace amounts of ethanol and for a longer time frame, being detectable even when no more ethanol is present. The instability of EtG against bacterial degradation in contaminated urine samples and/or the possible postcollection synthesis of this metabolite in samples containing, e.g., Escherichia coli and ethanol, may cause false identification of alcohol uptake. Therefore, it is of paramount importance to constrict these error sources by inhibition of any bacterial growth causing hydrolization or synthesis of EtG. This study evaluates a new method of collecting urine samples on filter paper, dried urine spots (DUS), for simultaneous detection of EtG, EtS and creatinine, having the great advantage of inhibiting bacterial activity. In addition, a method validation for the determination of EtG and EtS in DUS was performed according to the FDA guidelines. Sterile-filtered urine was spiked with EtG and EtS, inoculated with E. coli and incubated. Liquid and dried urine samples were collected after various time intervals up to 96 h. Liquid samples were frozen immediately after collection, whereas aliquots for DUS were pipetted onto filter paper, allowed to dry and stored at RT until analysis 1 week after. The specimens were analyzed by LC-ESI-MS/MS. As expected, degradation of EtG, but not of EtS, was observed in contaminated liquid urine samples. However, the specimens collected on filter paper and stored at RT showed no degradation during storage. Therefore, collecting urine samples on filter paper for EtG and EtS analysis turns out to be a reliable method to avoid bacterial degradation of EtG and EtS, and consequently, stabilization of these ethanol metabolites is achieved. In addition, simultaneous measurement of creatinine content as an indicator of urine dilution helps to interpret the results. Method validation for EtG and EtS in DUS was satisfactory, showing the linearity of the calibration curves in the studied concentration range, good precision, accuracy and selectivity. [ABSTRACT FROM AUTHOR]

Three-component reaction of N-methyl- or N,N-diethyl-3-oxobutanamide with aromatic aldehydes and tetrazol-5-amine monohydrate gave the corresponding N-substituted 7-aryl-5-methyl-4,7-dihydrotetrazolo-[1,5- a]pyrimidine-6-carboxamides. [ABSTRACT FROM AUTHOR]

Genome shuffling was used to improve the thermotolerance of l-glutamic acid-producing strain Corynebacteria glutamicum. Five strains with subtle improvements in high temperature tolerance and productivity were selected by ultraviolet irradiation and diethyl sulfate mutagenesis. An improved strain (F343) was obtained by three rounds of genome shuffling of the five strains as mentioned above. The cell density of F343 was four times higher than that of ancestor strains after 24 h of cultivation at 44°C, and importantly, the yield of l-glutamic acid was increased by 1.8-times comparing with that of the ancestor strain at 38°C in a 5-L fermentor. With glucose supplement and two-stage pH control, the l-glutamate acid concentration of F343 reached 119 g/L after fermentation for 30 h. The genetic diversity between F343 and its ancestors was also evaluated by amplified fragment length polymorphism analysis. Results suggest that the phenotypes for both thermotolerance and l-glutamic acid production in F343 were evolved. [ABSTRACT FROM AUTHOR]

The effect of an ionic liquid, 1-ethyl-3-methylimidazolium ethyl sulfate ([EMIm]ESO), on the thermophysical properties of aqueous D-glucose solutions including density, viscosity, and electrical conductivity have been investigated at 298.15 K. Using these properties, the apparent molar volumes, V, the viscosity B-coefficients and the molar conductivities, Λ, have been computed for the ternary D-glucose + [EMIm]ESO+water solutions. The V values were used to calculate the standard partial molar volumes, $V_{\phi}^{0}$, and transfer volumes, $\Delta_{\mathrm{tr}}V_{\phi}^{0}$, of D-glucose from water to aqueous ionic liquid solutions. These volumetric parameters, for all the solutions studied, are positive and increase monotonically with increasing the concentration of [EMIm]ESO. These observations have been interpreted in terms of the interactions between D-glucose and ionic liquid in the aqueous solution. The viscosity data were analyzed in terms of the Jones-Dole equation to determine the values of the viscosity B-coefficients. The calculated conductometric parameters, the limiting molar conductivities, Λ, the association constants, K, and the Walden products, Λ η, for [EMIm]ESO, decrease with increasing concentration of D-glucose. This trend suggests that the ions of an ionic liquid do not have the same hydrodynamic size in the presence of D-glucose molecules (ILs) and consequently provides evidence for the dehydration effect of the ionic liquid in aqueous D-glucose solutions. [ABSTRACT FROM AUTHOR]

Two methods for synthesis of ethidium bromide, a fluorescent dye widely used in molecular biology, were improved. An analog of ethidium bromide, ethidium ethyl sulfate, was synthesized. [ABSTRACT FROM AUTHOR]

Detection of the alcohol metabolites ethylglucuronide (EtG) and ethylsulfate (EtS) has become routine in many forensic laboratories over the last few years. Most previously published methods using liquid chromatography coupled with electrospray tandem mass spectrometry require a post-chromatographic addition of solvent and/or extensive sample preparation prior to analysis. The aim of the study was to develop a simplified method. To 20 μL urine, internal standard containing EtG- d5 and EtS- d was added and the mixture was treated with elution buffer internal standard. EtG and EtS were separated using a Shimadzu Prominence high performance liquid chromatography (HPLC) system with a C18 separation column (Restek Ultra Aqueous C18, 4.6 × 150 mm, 5 μm), using isocratic elution with a mobile phase consisting of 10 mM ammonium acetate buffer pH 7 (total run time, 6 min). The compounds were detected using an Applied Biosystems API 5000 liquid chromatography tandem mass spectrometry system (atmospheric pressure chemical ionization, multiple-reaction monitoring mode). The method was fully validated according to international guidelines. The assay was found to be selective for the compounds of interest. It was linear from 0.1 to 10 mg/L for all analytes ( R > 0.99). Matrix effects studies showed the presence of a slight but consistent ion enhancement ( n = 10 different urine samples) at low concentrations and no effects at higher concentrations. Accuracy data were between 0.75% and 8.1% bias for EtG and between −5.0% and −11.3% bias for EtS. Precision data were between 4.3% and 6.9% relative standard deviations (RSD) for EtG and between 6.0% and 7.5% RSD for EtS. No instability was observed after repeated freezing and thawing. This fast, reliable, and accurate method enables the detection and quantification of alcohol metabolites in urine. The method is easier to use and more sensitive than previously published methods. [ABSTRACT FROM AUTHOR]

new method for the determination of iron (III) has been described. The analytical procedure was based on the fluorescence quenching of salicylfluorone (SAF) by iron (III) and the fluorescence quenching value (ΔF) could be increased in the medium of room temperature ionic liquids (RTILs) (1-ethyl-3-methylimidazolium ethyl sulfate)/SDS (sodium dodecyl sulfate). The main factors influencing the fluorescence quenching (ΔF) were investigated in detail. Under the optimal conditions, the linear equation was $$ \Delta {\hbox{F }} = {\hbox{319c }} + {176}.{5}\; $$(c:μg·mL, r = 0.9936). The linear range of calibration curve was 0.2-1.1 μg·mL and the detection limit was 8.3 ng·mL. The preliminary sensitized mechanism was discussed with distribution coefficient and fluorescence quantum yield in different media. The method has been applied to the determination of Fe (III) in water samples with satisfactory results. [ABSTRACT FROM AUTHOR]

The hydrolysis of the herbicide safener mefenpyrdiethyl (1-(2, 4-dichlorophenyl)-4, 5-dihydro-5-methyl-1 H-pyrazole-3,5-dicarboxylic acid diethyl ester) was investigated in aqueous solutions in the pH range from 2 to 9 and the temperature range from 298 to 323 K. The kinetics of hydrolysis were pseudo first order and were found to be strongly pH and temperature dependent. While near-constant in acidic medium, the hydrolysis rates strongly increased in alkaline pH, and total hydrolysis was observed at pH 11. Two main hydrolysis products, mefenpyrethyl (monoester) and mefenpyr (dicarboxylic acid) were isolated by ultrahigh-pressure liquid chromatography (UHPLC) and characterized using high-resolution Fourier transform ion cyclotron resonance mass spectroscopy (ICR-FT/MS) as well as H, C and 2D NMR analyses. Additionally, a density functional theory (DFT) investigation explained the stability of the pesticide at pH 7 and the high reactivity of the pesticide in alkaline medium. The key nucleophilic reaction partner is hydroxyl ions instead of neutral water molecules. Furthermore, the calculated activation barrier for hydrolysis in alkaline medium is in agreement with the extrapolated and experimentally determined activation barrier at pH 14. [ABSTRACT FROM AUTHOR]

Urine testing for ethyl glucuronide (EtG) is used to spot recent alcohol intake and is utilized to document alcohol abstinence. However, other possible sources of ethanol existed when special beverages or foods were ingested. EtG concentration curves in urine were measured after the consumption of non-alcoholic beers, fruit juices, sauerkraut, and matured bananas. Using a cutoff of 0.1 mg/l, positive EtG findings were revealed after the ingestion of a lot of non-alcoholic beer up to 13 h later, sauerkraut up to 5 h later, and matured bananas up to 3.5 h later. In German abstinence programs, subjects have to deliver a urine sample within 24 h after advice, and all participants are informed about possible misleading results caused by the consumption of certain beverages or foods. With respect to the present results, a 0.1 mg/l cutoff can be considered useful, and misleading results should not be expected from informed subjects within a 24-h waiting period. [ABSTRACT FROM AUTHOR]

The titled new functionalized ligand of type 2-[(phenyl)-(3,5-dimethyl-pyrazol-1-yl)-methyl]-malonic acid diethyl ester ( 4) is prepared in good yield through condensation of 3,5-dimethyl-pyrazole, with 2-arylidene-malonic acid diethyl esters 3. The structure of 4 was determined by spectral (IR, H and C NMR), elemental analyses and X-ray diffraction data. The title compound ( 4) crystallizes in the monoclinic space group P2/a, with a = 7.9253 (2), b = 17.1299 (5), c = 13.4522 (4) Å, β = 90.220 (2)°, V = 1,826.25 (9) Å, Z = 4 and with R = 0.021. The molecular conformation shows two possible pockets ready to coordinate two metal atoms. The crystal structure of ( 4) is stabilized by inter-molecular C–H⋯O and C–H⋯N hydrogen bonding. Graphical Abstract: [Structure of 2-[(phenyl)-(3,5-dimethyl-pyrazol-1-yl)-methyl]-malonic acid diethyl ester. I. Meskini, L. Toupet,* M. Daoudi, A. Kerbal, M. Akkurt,* Z. H. Chohan and T. Ben Hadda* The molecular conformation shows two possible pockets ready to coordinate two metal atoms. The crystal structure of ( 4) is stabilized by inter-molecular C–H⋯O and C–H⋯N hydrogen bonding interactions] -->[Figure not available: see fulltext.]. [ABSTRACT FROM AUTHOR]