JBCS

The chiral thiourea catalyzed direct aldol reaction of unmodified methyl ynones under aqueous conditions is described. This procedure afforded β-hydroxyynones bearing a quaternary carbon center with moderate to good yields and enantioselectivities

A polyether glycol obtained from cardanol presented significant ability to the inhibition of methane hydrate

Optical nanobiosensors with nanometric-sized dimensions opened new researches for intra-cellular monitoring leading to develop sensitive robust and reproducible nanobiosensors. The sensors are equipped with immobilized bio-receptor probes, e.g. antibodies, enzyme substrate etc and these probes will revolutionize the future of disease diagnosis

We present four reactive ESIPT fluorescent 1,3,5-triazine derivatives from nucleophilic aromatic substitution of cyanuric chloride. The dyes are fluorescent by an intramolecular proton transfer mechanism in the blue-orange region with a large Stokes shift. The incorporation of the dyes into cellulose fibers could be done successfully

The d_π-orbital energy of three [Pt(PPh₃)₂(η².L)] compounds {L = C₂H₄, C₆₀ and C₂(CN)₄}, quantitatively determined by Pt L_2,3 X-ray absorption spectroscopy (XAS), follows the order [Pt(PPh₃)₂((η².C₂H₄)] < [Pt(PPh₃)₂((η².C₆₀)]) < [Pt(PPh₃)₂{(η².C₂(CN)₄}], in line with the π-acidity of the olefin ligands

Gas chromatography with pulsed flame photometric detector (GCPFPD) has proved to be an advantageous technique for tributyltin (TBT) quantification in crustacean tissues when performed after extraction with an apolar solvent (toluene) followed by Grignard derivatization

The work describes the catalytic activity of layered laurates in the methyl (ethyl) esterification reactions of lauric acid, for which conversions between 75 and 90% were observed. The catalysts were reused in three consecutive reaction cycles and some of them preserved the structure and retained the catalytic activity close to those observed in the first cycle

Polythiophene films were electropolymerized on the surface of metal (stainless steel) wires for the development of solid-phase microextraction (SPME). These polymeric films were evaluated as SPME phases for the liquid chromatography (LC) analysis of antidepressants in plasma samples for toxicological analysis purpose

ESI(+)-MS/MS spectra of protonated lumefantrine (m/z 528), showing rich dissociation chemistry. Water loss is the most favored initial dissociation forming the major fragment ion of m/z 510. This elimination is likely favored due to the formation of a highly stable, fully delocalized, resonance stabilized benzyl-like cation, which may rearranges to a tropylium-like ion

Migration of phthalate-based plasticizers from hemodialyzers

Schematic diagram for preconcentration and determination of zinc by in situ solvent formation microextraction based on use of ionic liquid (IL)) as an extractant solvent, sodium hexafluoro-phosphate (NaPF₆) as an ion-pairing agent, 1-(2-hydroxynaphtalene-1-yl) ethane oxime as complexing agent and detection by flame atomic absorption spectrometry

Docking, HQSAR, CoMFA and ESP maps for the most potent compound of the series

In seafood products is possible the conversion of free amino acid to biogenic amines by microbial decarboxylation, therefore, the proposed HPLC method here may be useful for evaluation of the sanitary quality of various shrimp by-products

This study compared four extraction procedures for the simultaneous determination of mycotoxins ochratoxin A and citrinin in samples of rice

Square-wave voltammograms and the corresponding analytical curve for various concentrations of DMZ in raw natural waters on the HMDE under optimum conditions

The electrochemical reduction of nitrate and nitrite is facilitated at copper cathodes after activation of the surface in acidic medium. To understand in more details the morphologic change of the surface during the activation process and its correlation with electrochemical properties, images of the copper surface were obtained by scanning electron microscopy (SEM) and atomic force microscopy (AFM)

The preparation of cytosporones A-C from the same starting material through a short synthetic route, with good yields, is reported. All compounds were tested for allelopathic activity on lettuce seeds. Cytosporone A and its methylated precursor showed remarkable allelopathic activity, inhibiting seed germination and seedling growth

Polychlorinated biphenyls were highly sensitively determined in seawater containing large amounts of humic substances by combining KMnO4 treatment and headspace solid-phase microextraction coupled with gas chromatography-mass spectrometry with the aid of experimental design

An easy method of application was developed for the determination of ammonia in ambient air. The samples are collected using cellulose filters impregnated with oxalic acid, followed of fluorimetric detection. The method is reliable for measuring low concentrations of ammonia and where there are rapid fluctuations in their concentrations

A new and extensively validated ultra-performance liquid chromatographic method for voriconazole measurement in plasma and oral fluid is presented. Run time was 4 min, with mobile phase comsuption of 2.2 mL per analysis. Panel A shows a chromatogram of a plasma sample and panel B shows the chromatogram of an oral fluid sample, both from the same patient

The domestic cooking effect of beans in the Fe, proteins and organic compounds distribution was evaluated by GF AAS, Bradford method and MALDI-TOF MS

Molecular modeling studies were carried out aiming to elucidate the molecular basis of the differential acetylcholinesterase inhibition profiles of the semi-synthetic derivatives (-)-3-O-acetyl-cassine hydrochloride (9) and (-)-3-O-acetyl-spectaline hydrochloride (10)

A series of metal halide hydrates was proved to be efficient Lewis acid catalysts promoting the multicomponent Radziszewski reaction for the triarylimidazole synthesis in alcoholic media. In absence of aldehyde, triaryloxazoles were obtained in good yields

Essential oils extracted from fruits of Schinus terebinthifolius Raddi were analyzed by GC and GC-MS, and evaluated for their reproductive toxicity on male rats. The results showed there are no toxic effects on male reproduction after treatment with essential oil at the tested doses

Fe₃S₂(CO)₉ catalyzes the electrochemical reduction of acetic acid to produce H₂; it mimics the [Fe-Fe] hydrogenase enzyme