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排序方式: 共有170条查询结果,搜索用时 31 毫秒
1.
Ana-Maria Udrea Andra Dinache Jean-Marie Pags Ruxandra Angela Pirvulescu 《Molecules (Basel, Switzerland)》2021,26(8)
Multidrug resistance of bacteria is a worrying concern in the therapeutic field and an alternative method to combat it is designing new efflux pump inhibitors (EPIs). This article presents a molecular study of two quinazoline derivatives, labelled BG1189 and BG1190, proposed as EPIs. In silico approach investigates the pharmacodynamic and pharmacokinetic profile of BG1189 and BG1190 quinazolines. Molecular docking and predicted ADMET features suggest that BG1189 and BG1190 may represent attractive candidates as antimicrobial drugs. UV-Vis absorption spectroscopy was employed to study the time stability of quinazoline solutions in water or in dimethyl sulfoxide (DMSO), in constant environmental conditions, and to determine the influence of usual storage temperature, normal room lighting and laser radiation (photostability) on samples stability. The effects of irradiation on BG1189 and BG1190 molecules were also assessed through Fourier-transform infrared (FTIR) spectroscopy. FTIR spectra showed that laser radiation breaks some chemical bonds affecting the substituents and the quinazoline radical of the compounds. 相似文献
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The C‐3 position of isoindazoles is readily functionalized by metalation with lithium diisopropylamide followed by reaction with a variety of electrophiles. 相似文献
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The formation of inclusion complexes of six essential oil (EO) components (β-caryophyllene, cis-ocimene, trans-ocimene, sabinene hydrate (thujanol), γ-terpinene and α-terpineol) with six cyclodextrins (CDs) (α-CD, β-CD, γ-CD, HP-β-CD, RAMEB and CRYSMEB) was investigated by using static headspace-gas chromatography and UV–visible spectroscopy. Retention studies showed that CDs could efficiently reduce the volatility of EO components except for β-caryophyllene with α-CD. In this case, no inclusion complex was detected while for other compounds the formation of 1:1 inclusion complexes was observed. Results revealed that the inclusion stability mainly depends on geometric complementarity between encapsulated molecule and CD's cavity. Molecular modelling was used to investigate the complementarities between host and guest. Thus, CDs could efficiently be regarded as promising encapsulants for EO components leading to improve their application in cosmetic, pharmaceutical and agriculture fields. 相似文献
6.
Abdelkrim Azzouz Vasilica-Alisa Aruş Nicoleta Platon Kamel Ghomari Ieana-Denisa Nistor Tze Chieh Shiao René Roy 《Adsorption》2013,19(5):909-918
Dendrimers bearing hydroxyl groups supported by layered double hydroxides (CO3–LDH) with Mg/Al ratio ranging from 1:1 to 5:1 showed improved properties for the reversible capture of carbon dioxide (CO2). The adsorption capacity of the starting LDH was due to the intrinsic base-like behavior, and was found to depend on the Mg/Al ratio. When contacted with polyol dendrimers in aqueous media, no intercalation took place. This was explained in terms of low exfoliation grade of LDH and hydrophobic character of the dendrimer molecules. The latter rather adsorb on the external surface of the LDH stacks for low dendrimer loadings, or aggregate into organic clusters for higher contents. Analyses through thermal programmed desorption of CO2 revealed that dendrimer incorporation advantageously attenuates the basicity strength of the starting LDH support, by lowering the desorption temperature. The OH groups of the organic moiety were found to display an amphoteric character, and act as the main adsorption sites. The weak interactions with CO2 facilitate easier release of the major part of adsorbed CO2 at temperature not exceeding 80–100 °C. On polyol organo-LDHs, the reversible CO2 retention was discussed herein in terms of acid–base interactions. This concept allows envisaging the capture of diverse pollutants and other greenhouse gases by modifying the chemical groups on the dendritic moiety. 相似文献
7.
Oana-Viorela Nistor Carmen Alina Bolea Doina-Georgeta Andronoiu Mihaela Cotrle Nicoleta Stnciuc 《Molecules (Basel, Switzerland)》2021,26(11)
Sea buckthorn (Hippophaė rhamnoides L.) is recognized as a valuable source of vitamin C and antioxidants, frequently used as nutraceuticals and cosmeceuticals. In the present study, attempts are made to produce and characterize a novel type of marmalade using sea buckthorn berries processed at 102 °C into marmalade in two combinations, with whole cane or stevia sugar. Changes in the phytochemical profile, antioxidant activity, color, shelf-life, texture, microbiological, and sensorial characteristics were determined. The total carotenoids content in the marmalades were significantly different, with values of 0.91 ± 0.03 mg/g dry weight (DW) in the sample with whole sugar cane (Cz) and 2.69 ± 0.14 mg/g DW in the sample with Stevia sugar (Cs). Significant values of polyphenols were found, of 59.41 ± 1.13 mg GAE/g DW in Cz and 72.44 ± 2.31 mg GAE/g DW in Cs, leading to an antioxidant activity of 45.12 ± 0.001 μMol Trolox/g DW and 118.07 ± 0.01 μMol Trolox/g DW, respectively. Accelerated storage study showed a decrease in all the phytochemicals, however no significant changes were found in antioxidant activity. Values of <100 CFU/g for yeasts and molds and <5 CFU/g for Enterobacteriaceae after 21 days of storage at the room temperature of the marmalades were determined. The sensorial and color results were more than acceptable. Overall, the results highlighted the potential of using sea buckthorn as a potential rich source of bioactive compounds to be used in the sugar-based products manufacturing. 相似文献
8.
Raluca Nicoleta Darie Eduard Lack Franz Lang Jr. Martin Sova Alexandra Nistor Iuliana Spiridon 《International Journal of Polymer Analysis and Characterization》2014,19(5):453-467
New materials were obtained by incorporating in polypropylene (PP) matrix 60% wood wastes resulting after extraction with supercritical carbon dioxide, water, and ethanol. Structural, mechanical, thermal, and rheological characterizations, as well as moisture uptake of the composites, were evaluated before and after accelerated weathering. It was found that the extraction method influenced the composite properties due to the hydrophilic-hydrophobic balance. The addition of extracted fibers results in an increase in hardness and tensile properties and a decrease of impact strength as compared to PP. 相似文献
9.
L. C. Nistor S. V. Nistor V. Teodorescu M. M. Voda 《Crystal Research and Technology》1989,24(10):1059-1064
The moisture resistance of ultratransparent KCl grown in a reactive atmosphere was studied on polished KCl samples coated with protective films of BaF2. The lifetime was improved about 4 times compared with uncoated samples. A further improvement was obtained by additional chemical polishing before coating. However, in such a case buckling of the film in a pattern of narrow parallel stripes was observed in an intermediate stage of the humidity test. 相似文献
10.
L. C. Nistor S. V. Nistor V. Teodorescu I. Voicu 《Crystal Research and Technology》1979,14(12):1525-1528
Single crystals of CaF2 doped with ThO2 were grown by the Czochralski-Kyropoulos technique in graphite crucibles. The distribution of thorium in the as grown crystals has been investigated by optical and transmission electron microscopy, selected area diffraction and optical spectroscopy. 相似文献