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Morteza Moradi et al.
The Analyst, 137(15), 3549-3557 (2012-06-27)
Hollow fiber-based liquid phase microextraction (HF-LPME) using conventional solvents is limited by their relative instability and high volatility. The use of supramolecular solvents as a liquid membrane phase could overcome these inconveniences due to their negligible vapour pressure and high...
Haji Bahadar et al.
Environmental toxicology and pharmacology, 39(3), 1161-1169 (2015-05-04)
Benzene (C6H6) is an organic compound used in petrochemicals and numerous other industries. It is abundantly released to our environment as a chemical pollutant causing widespread human exposure. This study mainly focused on benzene induced toxicity on rat pancreatic islets...
New media in homogeneous catalysis: wet sodium or tetrabutylammonium hydrogensulfate salts for reppe syntheses catalyzed by a ru (ii) carbonyl complex.
Pardey AJ, et al.
Journal of Coordination Chemistry, 57(10), 871-882 (2004)
Muhammet Uyanik et al.
Science (New York, N.Y.), 345(6194), 291-294 (2014-07-19)
The diverse biological activities of tocopherols and their analogs have inspired considerable interest in the development of routes for their efficient asymmetric synthesis. Here, we report that chiral ammonium hypoiodite salts catalyze highly chemo- and enantioselective oxidative cyclization of γ-(2-hydroxyphenyl)ketones...
Manas K Ghorai et al.
The Journal of organic chemistry, 77(8), 3740-3753 (2012-03-28)
Lewis acid catalyzed quaternary ammonium salt mediated highly regioselective ring-opening of chiral activated aziridines and azetidines with alcohols to nonracemic β- and γ-amino ethers has been developed. The reaction mainly proceeds via an S(N)2 pathway, and the partial racemization of...
Svante Vikingsson et al.
Journal of pharmaceutical and biomedical analysis, 75, 145-152 (2012-12-25)
A high-performance liquid chromatography method capable of measuring thiopurine mono-, di-, and triphosphates separately in red blood cells (RBCs) was developed. RBCs were isolated from whole blood using centrifugation. Proteins were precipitated using dichloromethane and methanol. The thioguanine nucleotides (TGNs)...
K M Frankowski et al.
Journal of dairy science, 97(9), 5356-5370 (2014-07-16)
Many food companies are trying to limit the amount of sodium in their products. Permeate, the liquid remaining after whey or milk is ultrafiltered, has been suggested as a salt substitute. The objective of this study was to determine the...
Samy Mohamady et al.
Current protocols in nucleic acid chemistry, Chapter 13, Unit13-Unit13 (2012-12-21)
This unit describes a method for preparing nucleoside polyphosphates and their conjugates such as nucleoside triphosphates, symmetrical and unsymmetrical dinucleoside polyphosphates and sugar nucleotides. The protocols employ sulfonyl imidazolium salts (SnISs) as coupling reagents. These reagents are prepared in two...
Matt Petrowsky et al.
The journal of physical chemistry. B, 116(33), 10098-10105 (2012-07-31)
Onsager's model of the dielectric constant is used to provide a molecular-level picture of how the dielectric constant affects mass and charge transport in organic liquids and organic liquid electrolytes. Specifically, the molecular and system parameters governing transport are the...
Hiroyuki Nakao et al.
Biochimica et biophysica acta, 1848(1 Pt A), 145-150 (2014-10-15)
KcsA is a pH-dependent potassium channel that is activated at acidic pH. The channel undergoes global conformational changes upon activation. We hypothesized that the open-close conformational changes of the transmem brane region could promote the flip-flop of phosphoiipids. Based on...
Erbo Shi et al.
Organic letters, 14(13), 3384-3387 (2012-06-27)
A metal-free C-H oxidation for the construction of allylic esters has been developed. The use of a commercially available and inexpensive catalyst and oxidant, and readily available starting materials, coupled with the operational simplicity of the reaction, renders the methodology...
Fabio Galeotti et al.
Journal of chromatography. A, 1284, 141-147 (2013-03-05)
In this study, by using tetrabutylammonium bisulfate as ion-pairing reagent, we were able to separate all the main heparin/heparan sulfate disaccharides generated by the action of heparinases along with the main Hep tetrasaccharide possessing a 3-O-sulfate group on the sulfoglucosamine...
Juan M Quiles et al.
Food and chemical toxicology : an international journal published for the British Industrial Biological Research Association, 83, 222-228 (2015-07-07)
Aflatoxins (AFs) are secondary metabolites produced by different species of Aspergillus, such as Aspergillus flavus and Aspergillus parasiticus, which possess mutagenic, teratogenic and carcinogenic activities in humans. In this study, active packaging devices containing allyl isothiocyanate (AITC) or oriental mustard...
Oliver Bixner et al.
The Journal of chemical physics, 136(20), 204503-204503 (2012-06-07)
The interaction of exciton and charge transfer (CT) states plays a central role in photo-induced CT processes in chemistry, biology, and physics. In this work, we use a combination of two-dimensional electronic spectroscopy (2D-ES), pump-probe measurements, and quantum chemistry to...
Mei Shen et al.
Journal of the American Chemical Society, 134(24), 9856-9859 (2012-06-05)
Here we report on the unprecedentedly high resolution imaging of ion transport through single nanopores by scanning electrochemical microscopy (SECM). The quantitative SECM image of single nanopores allows for the determination of their structural properties, including their density, shape, and...
Huanhuan Zhang et al.
Environmental toxicology and chemistry, 34(7), 1499-1504 (2015-03-17)
Analytical methods for determining perfluoroalkyl acids (PFAAs) in leaves were developed to quantify a suite of analytes in both coniferous and deciduous broad-leaved trees. Sodium hydroxide-methanol and solid-phase extraction was selected as the extracting and cleanup strategy for PFAA analysis....
Suresh Dharuman et al.
The Journal of organic chemistry, 78(17), 8442-8450 (2013-08-13)
A reagent system comprising tetrabutylammonium nitrate-trifluoroacetic anhydride-triethylamine has been developed for the synthesis of 2-nitroglycals from various protected glycals. The base-catalyzed Ferrier rearrangement on tri-O-acetylated 2-nitroglycals has been reported for the first time. Reactivity of these nitroacetates and associated selectivity...
Ying-Chieh Wong et al.
Organic letters, 14(23), 6024-6027 (2012-11-30)
The radical cascade protocol of the α-cyano α-TMS/aryl-capped alkynyl aryl ketones promoted by tert-butyl hydroperoxide under catalysis with tetrabutylammonium iodide in refluxing benzene has been developed, leading to the construction of a variety of highly functionalized [6,6,5] tricyclic frameworks in...
A J Chinchalikar et al.
The European physical journal. E, Soft matter, 35(7), 55-55 (2012-07-06)
Clouding is studied by small-angle neutron scattering (SANS) on a charged micellar system of sodium dodecyl sulphate (SDS) and tetrabutylammonium bromide (TBAB) with varying temperature and salt NaCl. We show that the clouding occurs as a result of increase in...
Muhammet Uyanik et al.
Molecules (Basel, Switzerland), 17(7), 8604-8616 (2012-07-20)
We have developed the first example of hypervalent iodine(V)-catalyzed regioselective oxidation of phenols to o-quinones. Various phenols could be oxidized to the corresponding o-quinones in good to excellent yields using catalytic amounts of sodium salts of 2-iodobenzenesulfonic acids (pre-IBSes) and...
R Bryan Sears et al.
Journal of inorganic biochemistry, 121, 77-87 (2013-01-29)
The complex cis-[Ru(phpy)(phen)(CH3CN)2](+) (phpy=2-phenylpyridine, phen=1,10-phenanthroline) was investigated as a potential photodynamic therapy (PDT) agent. This complex presents desirable photochemical characteristics including a low energy absorption tail extending into the PDT window (600-850nm) and photoinduced exchange of the CH3CN ligands, generating...
Yohei Ishibashi et al.
The Journal of biological chemistry, 290(29), 18245-18260 (2015-06-07)
The membrane glycolipid glucosylceramide (GlcCer) plays a critical role in cellular homeostasis. Its intracellular levels are thought to be tightly regulated. How cells regulate GlcCer levels remains to be clarified. AMP-activated protein kinase (AMPK), which is a crucial cellular energy...
Javier Gualix et al.
Purinergic signalling, 10(2), 349-356 (2013-08-15)
Diadenosine triphosphate (Ap(3)A), diadenosine tetraphosphate (Ap(4)A), and diadenosine pentaphosphate (Ap(5)A) have been identified in microdialysis samples from the cerebellum of conscious freely moving rats, under basal conditions, by means of a high-performance liquid chromatography method. The occurrence of Ap(3)A in...
Shohei Sakashita et al.
Organic letters, 15(17), 4308-4311 (2013-08-21)
Palladium-catalyzed Suzuki-Miyaura cross-coupling reactions of tetrabutylammonium 2-pyridyltriolborate salts with various aryl (heteroaryl) chlorides can produce the corresponding desired coupling products with good to excellent yields. These tetrabutylammonium salts are more reactive than the corresponding lithium salts. The coupling reactions with...
Kosei Sugahara et al.
Chemical communications (Cambridge, England), 48(67), 8422-8424 (2012-07-14)
A tetra-n-butylammonium (TBA) salt of a γ-Keggin -6-charged germanodecatungstate, [γ-H(2)GeW(10)O(36)](6-) (I), could act as an efficient homogeneous catalyst for Knoevenagel condensation of active methylene compounds with carbonyl compounds.
Carolina Cortés-Herrera et al.
Foods (Basel, Switzerland), 8(1) (2018-12-24)
Food and feed laboratories share several similarities when facing the implementation of liquid-chromatographic analysis. Using the experience acquired over the years, through application chemistry in food and feed research, selected analytes of relevance for both areas were discussed. This review...
Shintaro Itagaki et al.
Chemical communications (Cambridge, England), 48(74), 9269-9271 (2012-08-10)
In the presence of Rh(2)(OAc)(4) (OAc = acetate) and TBA(2)WO(4) (TBA = tetra-n-butylammonium), the N-silylation of indole derivatives with hydrosilanes efficiently proceeded to give the corresponding N-silylated indoles in high yields. Pyrrole and carbazole were also N-silylated with the combined...
Maria-Teresa Weichler et al.
Applied and environmental microbiology, 81(14), 4564-4572 (2015-04-26)
The recent discovery of a coenzyme B12-dependent acyl-coenzyme A (acyl-CoA) mutase isomerizing 3-hydroxybutyryl- and 2-hydroxyisobutyryl-CoA in the mesophilic bacterium Aquincola tertiaricarbonis L108 (N. Yaneva, J. Schuster, F. Schäfer, V. Lede, D. Przybylski, T. Paproth, H. Harms, R. H. Müller, and...
Purnandhu Bose et al.
Chemistry, an Asian journal, 7(10), 2373-2380 (2012-07-26)
A new series of tris(2-aminoethyl)amine (tren)-based L-alanine amino acid backboned tripodal hexaamide receptors (L1-L5) with various attached moieties based on electron-withdrawing fluoro groups and lipophilicity have been synthesized and characterized. Detailed binding studies of L1-L5 with different anions, such as...
Derivatization and solid-phase microextraction
Stashenko.EE and Martinez.RJ
TrAC, Trends in Analytical Chemistry, 23(8), 553-561 (2004)
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