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211.
Delia Soto-Castro 《Tetrahedron》2006,62(51):12116-12125
Four dendrimeric fragments (FPs) were designed to encapsulate a family of drugs known as salicylanilides (importantly acaricides/anthelminthics), mainly by H-bonding. The experimental system: PAMAM-DBNP (2,6-dibromo-4-nitrophenol) was also calculated as a reference. The efficiency of encapsulation is related to the presence of functional groups like amide and alcohol, the flexibility of the aliphatic chains, and efficient pre-organization before the encapsulation. All the geometry optimizations were carried out at DFT/LAV3P∗ level of theory. Two hybrid functionals were tested: B3LYP and BHandHLYP. The last one shows improved performance in describing close contacts as well as better agreement with experimental observations for the complex PAMAM-BDNP. 相似文献
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Sandra Resa Dr. Angel Orte Dr. Delia Miguel Dr. Jose M. Paredes Virginia Puente‐Muñoz Dr. Rafael Salto Dr. Maria D. Giron Dr. Maria J. Ruedas‐Rama Dr. Juan M. Cuerva Prof. Jose M. Alvarez‐Pez Dr. Luis Crovetto 《Chemistry (Weinheim an der Bergstrasse, Germany)》2015,21(42):14772-14779
The simultaneous detection of relevant metabolites in living organisms by using one molecule introduces an approach to understanding the relationships between these metabolites in healthy and deregulated cells. Fluorescent probes of low toxicity are remarkable tools for this type of analysis of biological systems in vivo. As a proof of concept, different naturally occurring compounds, such as biothiols and phosphate anions, were the focus for this work. The 2,4‐dinitrobenzenesulfinate (DNBS) derivative of 9‐[1‐(4‐tert‐butyl‐2‐methoxyphenyl)]‐6‐hydroxy‐3H‐xanthen‐3‐one (Granada Green; GG) were designed and synthesized. This new sulfinyl xanthene derivative can act as a dual sensor for the aforementioned analytes simultaneously. The mechanism of action of this derivative implies thiolysis of the sulfinyl group of the weakly fluorescent DNBS‐GG by biological thiols at near‐neutral pH values, thus releasing the fluorescent GG moiety, which simultaneously responds to phosphate anions through its fluorescence‐decay time. The new dual probe was tested in solution by using steady‐state and time‐resolved fluorescence and intracellularly by using fluorescence‐lifetime imaging microscopy (FLIM) in human epithelioid cervix carcinoma (HeLa) cells. 相似文献
214.
Simona Bungau Cosmin Mihai Vesa Areha Abid Tapan Behl Delia Mirela Tit Anamaria Lavinia Purza Bianca Pasca Laura Maghiar Todan Laura Endres 《Molecules (Basel, Switzerland)》2021,26(9)
Withaferin A (WFA) was identified as the most active phytocompound of the plant Withania somnifera (WS) and as having multiple therapeutic/ameliorating properties (anticancer, antiangiogenic, anti-invasive, anti-inflammatory, proapoptotic, etc.) in case of various diseases. In drug chemistry, WFA in silico approaches have identified favorite biological targets, stimulating and accelerating research to evaluate its pharmacological activity—numerous anticancer effects manifested in various organs (breast, pancreas, skin, colon, etc.), antivirals, anti-infective, etc., which are not yet sufficiently explored. This paper is a synthesis of the most relevant specialized papers in the field that are focused on the use of WFA in dermatological diseases, describing its mechanism of action while providing, at the same time, details about the results of its testing in in vitro/in vivo studies. 相似文献
215.
Delia Ionescu-Kruse 《Journal of Nonlinear Mathematical Physics》2015,22(4):523-530
In this paper we present a dynamical study of the exact nonlinear Pollard wave solution to the geophysical water-wave problem in the f-plane approximation. We deduce an exact dispersion relation and we discuss some properties of this solution. 相似文献
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217.
Delia A. Haynes Eric J. L. McInnes Jack Passmore Jeremy M. Rawson 《Phosphorus, sulfur, and silicon and the related elements》2013,188(4-5):869-873
Condensation of CF3C(═NH)NH2 with SCl2 yielded the dithiadiazolylium salt, [CF3CNSSN]Cl which could be reduced to [CF3CNSSN]2 with Zn/Cu couple in SO2. [CF3CNSSN]2 is a diamagnetic dimer in the solid state but melts at 308 K to give a paramagnetic liquid. On cooling the radical enters a metastable state before immediately re-solidifying below 295 K. The thermal hysteresis was probed by EPR spectroscopy. Metastable samples spontaneously solidified after an induction period, typically between ca. 5 and 30 min, consistent with the variable time necessary to form a seed crystal from which crystallization can occur. 相似文献
218.
Hans Bock Zdenek Havlas Delia Hess Christian Nther 《Angewandte Chemie (International ed. in English)》1998,37(4):502-504
Quite unexpectedly, all three electrons are taken up by the same anthryl moiety when 9,9′-bianthryl is reduced with an excess of sodium metal. Thanks to the “right” ligand/solvent mixture the first radical trianion salt (depicted on the right) could be isolated. It is a contact-ion quadruple of bianthryl in which all three Na+ counterions coordinate to the same half of the hydrocarbon molecule. 相似文献
219.
The formation of solid solution and ZrO2 phase stabilization were investigated by Raman spectroscopy and X‐ray diffraction (XRD) in calcium‐containing and cadmium‐containing zirconium oxide samples heated at 1073 K in air. The adopted preparation procedure led to the incorporation of calcium and cadmium in solid solution into the zirconia structure. The solid solution favored the tetragonal and cubic zirconia phases at the expense of the thermodynamically stable monoclinic modification. Combined macro‐ and micro‐Raman spectroscopy disclosed that instead of forming a homogeneous phase t″, intermediate between the tetragonal t′ and the cubic phase, the tetragonal and cubic phases coexisted in the range 9.49–13.89 mol% for Ca and 11.88–17.23 mol% for Cd. At higher dopant contents the cubic form stabilized. The impurity content necessary to stabilize the high‐symmetry phases was defined. Copyright © 2007 John Wiley & Sons, Ltd. 相似文献
220.