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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
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)
Soumen Ghosh et al.
Spectrochimica acta. Part A, Molecular and biomolecular spectroscopy, 149, 869-874 (2015-05-24)
A series of Schiff bases synthesized by the condensation of benzohydrazide and -NO2 substituted benzaldehyde have been used as selective fluoride ion sensor. Test paper coated with these synthetic Schiff bases (test kits) can detect fluoride ion selectively with a
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
Santosh Kumar Behera et al.
Photochemical & photobiological sciences : Official journal of the European Photochemistry Association and the European Society for Photobiology, 14(12), 2225-2237 (2015-10-31)
The mechanism for the dual emission of 2-(4'-N,N-dimethylaminophenyl)imidazo[4,5-c]pyridine (DMAPIP-c) in protic solvents was investigated by synthesizing and studying its analogues. Theoretical calculations were carried out to corroborate the experimental findings. The deprotonation studies suggest that the enhancement in the TICT
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
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
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
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
Nancy AlHaddad et al.
Organic & biomolecular chemistry, 17(31), 7330-7336 (2019-07-18)
The present study describes the synthesis of the first phenoxycalix[4]pyrrole-epichlorohydrin based polymer. The advantage of the latter resides in its fast-single step synthesis protocol, low cost, water insolubility and its unexpected anion extraction capacity. The study of this polymer by
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
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
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
I P E Macário et al.
Scientific reports, 9(1), 3932-3932 (2019-03-10)
The tailor-made character of deep eutectic solvents (DES) turns them very attractive to be used in several applications, including in health-related areas such as pharmaceutical, nutraceutical, and cosmetic industries. However, although DES has been touted as "green" solvents, several works
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
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
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
Noelia Luque et al.
Journal of chromatography. A, 1248, 74-83 (2012-06-26)
The suitability of a mixed-mode sorbent made up of admicelles of sodium dodecyl sulphate (SDS) and tetrabutylammonium (TBA) to extract and preserve pesticides from river and underground water was assessed. Pesticides belonging to different structural groups (i.e. triazines, carbamates, phenylureas
Peter S Toth et al.
The Analyst, 140(6), 1947-1954 (2015-02-11)
Two-phase voltammetry has been carried out using a reverse cell configuration, i.e. with the lower density organic solvent on the top of the aqueous solution in the cell, where the organic solvents contain either nitrile or ketone functional groups. The
Rosa M Suárez et al.
Molecules (Basel, Switzerland), 17(8), 8735-8741 (2012-07-27)
The synthesis of 9,9'-[1,2-ethanediylbis(oxymethylene)]bis-2-amino-1,9-dihydro-6H-purin-6-one, a minor impurity of acyclovir, is described. Starting with commercial N-(9-acetyl-6-oxo-1H-purin-2-yl)acetamide, the process uses an acid catalysed phase transfer catalysis (PTC) process to produce the selective alkylation at the 9 position of the guanine ring.
Shuhui Liu et al.
Journal of chromatography. A, 1420, 26-34 (2015-10-20)
Edible oil is easily contaminated with phthalic acid esters (PAEs). Conventional procedures to analyze individual PAEs require very rigorous experimental conditions that are extremely labor-intensive due to significant procedural contaminations generated by the ubiquitous presence of PAEs in the laboratory
Ye Rin Choi et al.
Chemical communications (Cambridge, England), 48(83), 10346-10348 (2012-09-18)
A series of synthetic molecules bearing the same hydrogen bonding mode observed in StClC were prepared and their transport ability of chloride ion across a lipid membrane was systematically optimized.
Toshihiro Kimura et al.
Inorganic chemistry, 51(23), 13001-13008 (2012-11-15)
A simple monomeric tungstate, TBA(2)[WO(4)] (I, TBA = tetra-n-butylammonium), could act as an efficient homogeneous catalyst for chemical fixation of CO(2) with 2-aminobenzonitriles to quinazoline-2,4(1H,3H)-diones. Various kinds of structurally diverse 2-aminobenzonitriles could be converted into the corresponding quinazoline-2,4(1H,3H)-diones in high
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
Jacek Cieślak et al.
Current protocols in nucleic acid chemistry, Chapter 4, Unit4-Unit4 (2012-09-08)
The conversion of 3',5'-disilylated 2'-O-(methylthiomethyl)ribonucleosides to 2'-O-(phthalimidooxymethyl)ribonucleosides is achieved in yields of 66% to 94%. Desilylation and dephtalimidation of these ribonucleosides by treatment with NH(4)F in MeOH produce 2'-O-aminooxymethylated ribonucleosides, which are efficient in producing stable and yet reversible 2'-conjugates
Veronika F S Pape et al.
Journal of inorganic biochemistry, 144, 18-30 (2015-01-16)
Three novel pyrimidinylhydrazones substituted at either the aromatic moiety or at the imine carbon atom were synthesized and characterized by standard analytical methods. All compounds were found to be toxic in the micro- to submicromolar range against a diverse panel
Nail Altunay et al.
Food chemistry, 310, 125933-125933 (2019-12-14)
In this study, a novel, simple and economic vortex-assisted alcohol-based deep eutectic solvent microextraction (VA-DES-ME) procedure has been developed for the preconcentration of curcumin in food samples prior to its spectrophotometric determination. A alcohol-based-DES consists of betaine hydrochloride - glycerol
Ya-Wen Chang et al.
Physical review letters, 108(24), 247802-247802 (2012-09-26)
The phase behavior of charged disk suspensions displays a strong dependence on ionic strengths, as the interplay between excluded volume and electrostatic interactions determines the formation of glasses, gels, and liquid crystal states. The various ions in natural soil or
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