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301.
Rajic Z Zorc B Raic-Malic S Ester K Kralj M Pavelic K Balzarini J De Clercq E Mintas M 《Molecules (Basel, Switzerland)》2006,11(11):837-848
3,5-Disubstituted hydantoin (1,3-imidazolidinedione) derivatives 5a-h were prepared by base induced cyclization of the corresponding N-(1-benzotriazolecarbonyl)-L- and D-amino acid amides 4a-h. Compounds 5a-h were evaluated for their cytostatic and antiviral activities. Among all the compounds evaluated, 3-benzhydryl-5-isopropyl hydantoin (5a) showed a weak but selective inhibitory effect against vaccinia virus (EC(50) = 16 microg/mL; selectivity index: 25). 3-Cyclohexyl-5-phenyl hydantoin (5g) showed inhibitory activity against cervical carcinoma (HeLa, IC(50) = 5.4 microM) and breast carcinoma (MCF-7, IC(50) = 2 microM), but also cytotoxic effects towards human normal fibroblasts (WI 38). On the contrary, the 3-benzhydryl-5-phenyl substituted hydantoin derivative 5h showed moderate inhibitory activity towards HeLa, MCF-7, pancreatic carcinoma (MiaPaCa-2), lung carcinoma (H 460) and colon carcinoma (SW 620) (IC(50) = 20-23 microM), but no effect on WI 38. 相似文献
302.
Bernhard Welz Lísia M.G. dos Santos Rennan G.O. Araujo Silvana do C. Jacob Maria Goreti R. Vale Michael Okruss Helmut Becker-Ross 《Spectrochimica Acta Part B: Atomic Spectroscopy》2010
The simultaneous determination of cadmium and iron in plant and soil samples has been investigated using high-resolution continuum source graphite furnace atomic absorption spectrometry. The primary cadmium resonance line at 228.802 nm and an adjacent secondary iron line at 228.726 nm, which is within the spectral interval covered by the charge-coupled device (CCD) array detector, have been used for the investigations. Due to the very high iron content in most of the soil samples the possibility has been investigated to reduce the sensitivity and extend the working range by using side pixels for measurement at the line wings instead of the line core. It has been found that the calibration curves measured at all the analytically useful pixels of this line consisted of two linear parts with distinctly different slopes. This effect has been independent of the positioning of the wavelength, i.e., if the Cd line or the Fe line was in the center of the CCD array. The most likely explanation for this unusual behavior is a significant difference between the instrument width ΔλInstr and the absorption line width ΔλAbs, which is quite pronounced in the case of Fe. Using both parts of the calibration curves and simultaneous measurement at the line center and at the wings made it possible to extend the working range for the iron determination to more than three orders of magnitude. 相似文献
303.
We state a Wiener criterion for the regularity of points with respect to a relaxed Dirichlet problem for a p-homogeneous Riemannian Dirichlet form. 相似文献
304.
Hapiuk D Marques MA Melinon P Flores-Livas JA Botti S Masenelli B 《Physical review letters》2012,108(11):115903
The issue of p doping in nanostructured cagelike ZnO is investigated by state-of-the-art calculations. Our study is focused on one prototypical structure, namely, sodalite, for which we show that p-type doping is possible for elements of the V, VI, and VII columns of the periodic table. However, some dopants tend to form dimers, thus impairing the stability of this kind of doping. This difference of behavior is discussed, and two criteria are proposed to ensure stable p doping. 相似文献
305.
Esteban Bertsch Sebastián Suñer Dr. Silvana Pinheiro Prof. Dr. William J. Zamora 《Chemphyschem》2023,24(24):e202300548
Lipophilicity is a physicochemical property with wide relevance in drug design, computational biology, food, environmental and medicinal chemistry. Lipophilicity is commonly expressed as the partition coefficient for neutral molecules, whereas for molecules with ionizable groups, the distribution coefficient (D) at a given pH is used. The logDpH is usually predicted using a pH correction over the logPN using the pKa of ionizable molecules, while often ignoring the apparent ion pair partitioning . In this work, we studied the impact of on the prediction of both the experimental lipophilicity of small molecules and experimental lipophilicity-based applications and metrics such as lipophilic efficiency (LipE), distribution of spiked drugs in milk products, and pH-dependent partition of water contaminants in synthetic passive samples such as silicones. Our findings show that better predictions are obtained by considering the apparent ion pair partitioning. In this context, we developed machine learning algorithms to determine the cases that should be considered. The results indicate that small, rigid, and unsaturated molecules with logPN close to zero, which present a significant proportion of ionic species in the aqueous phase, were better modeled using the apparent ion pair partitioning . Finally, our findings can serve as guidance to the scientific community working in early-stage drug design, food, and environmental chemistry. 相似文献
306.
Tiago F. T. Cerqueira Sun Lin Maximilian Amsler Stefan Goedecker Silvana Botti Miguel A. L. Marques 《ChemInform》2015,46(38):no-no
Ab initio global structural prediction and specifically, the minima hopping method combined with high‐throughput calculations are used to explore the periodic table in search of novel oxide phases. 相似文献
307.
Rojas Víctor Cáceres Gustavo López Silvana Henríquez Rodrigo Grez Paula Schrebler Ricardo Navarrete Emilio Herrera Francisco Caballero Álvaro Gómez-Cámer Juan Luis Aristizábal Juliet Muñoz Eduardo 《Journal of Solid State Electrochemistry》2023,27(4):865-872
Journal of Solid State Electrochemistry - In this work, the performance of copper (II) hexacyanoferrate(III) (CuHCF) as a cathode material for sodium-ion batteries was studied. The compound was... 相似文献
308.
Prof. Dr. Antonio Doménech-Carbó Silvana López Bastián Chandía Gustavo Cáceres Prof. Dr. Eduardo Muñoz 《Chemphyschem》2023,24(9):e202200853
The cation-insertion solid state electrochemistry of a potassium copper(II) hexacyanoferrate in contact with LiClO4/DMSO, NaPF6/DMSO, and KPF6/DMSO electrolytes has been theoretically and experimentally studied using the voltammetry of immobilized particles methodology. Voltammetric data, combined with SEM/EDS analysis permit to determine a K0.876CuII1.328FeIII0.049[FeIII0.318FeII0.682(CN)6] stoichiometry for the synthesized solid. Separation of electronic and ionic contributions to Gibbs energy changes can be made based on cyclic voltammetric and open circuit potential measurements. These parameters can be combined to measure values of the Gibbs energy of cation-independent electron transfer of 7.2±0.4 (K+), 7.1±0.5 (Na+) kJ mol−1, in close agreement with the expected independence of this parameter on the electrolyte cation. The reduction Fe(III) centers bound to cyano groups exhibit a cation-dependent, essentially Nernstian character which can be described in terms of Na+ and K+ insertion/deinsertion while in the case of Li+ electrolytes there is significant co-cation diffusion. Chronoamperometric data provide estimates of the diffusion coefficients of Na+, and K+ ions through the solid around 10−9 cm2 s−1. 相似文献
309.
Jun Okuda Thomas Kleinhenn Peter Knig Insa Taden Silvana Ngo Ilya L. Rushkin 《Macromolecular Symposia》1995,95(1):195-202
Mono(cyclopentadienyl)titanium complexes of the general formula Ti(η5-C5R5)X2OR' were designed as structurally well-defined mononuclear initiators for the ring-opening polymerization of four-, six-, and seven-membered lactones. Living pseudo-anionic mechanism with acyl-oxygen cleavage is suggested by various NMR spectroscopic studies as well as the isolation of the mono(insertion) products. The nature of the ancillary ligands lead to significant changes in the polymerization activity and is discussed in terms of electronic and steric effects. 相似文献