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81.
A. T. Soldatenkov I. A. Bekro Zh. A. Mamyrbekova S. A. Soldatova A. Temesgen N. D. Sergeeva L. N. Kuleshova V. N. Khrustalev 《Chemistry of Heterocyclic Compounds》1996,32(2):197-201
N-Alkyl substituted 4 phenyl-1.2,5,6-tetrahydropyridines which do not undergo Wagner hydroxylation are converted in good yields to the corresponding 3,4-dihydroxy-2-oxopiperidines under modified conditions for this reaction. The molecular structures of a 3,4-dihydroxy-4-phenylpiperidin-2-one and its diacetatate have been studied by x-ray crystalographic analysis.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 2, pp. 222–226, February, 1996. 相似文献
82.
Background
The extracts from the aerial parts of Portulaca quadrifida have been reported to show the total flavonoid content, antioxidant and antibacterial activities.Results
Our results revealed that the total flavonoid content of methanol and chloroform extracts is 2.335?±?0.0097 and 1.7312?±?0.0082 mgQE/100 g respectively. The two extracts also showed good antioxidant activity and total phenolic content as well as weak to moderate antibacterial activity against some bacteria.Conclusions
The extracts the aerial parts of the P. quadrifida showed good total flavonoid content, DPPH radical scavenging activity and antibacterial activity. In addition to this, the extracts also showed the presence of some important compounds by phytochemical analysis.
83.
Letícia R. Teixeira Rubén D. Sinisterra Rafael P. Vieira Aline Scarlatelli-Lima Márcio F.D. Moraes Maria Carolina Doretto Ângelo M. Denadai Heloisa Beraldo 《Journal of inclusion phenomena and macrocyclic chemistry》2006,54(1-2):133-138
A non-hygroscopic pharmaceutical composition was obtained following a host-guest strategy that used the anticonvulsant drug
sodium valproate (VA) and α-cyclodextrin. The pharmaceutical composition was fully characterized by thermal analyses (TG/DTG,
DSC), X-ray powder diffraction and by 1H, 13C, hydrogen relaxation times (T1) and 2D-ROESY NMR techniques. Isothermal titration calorimetry (ITC) was used to determine the VA:α-CD 1:1 stoichiometry
as well as to calculate the equilibrium constant (K) and thermodynamic energies of interaction (ΔGo, ΔHo and TΔSo). 相似文献
84.
Sahel Fajal Atikur Hassan Writakshi Mandal Mandar M. Shirolkar Sumanta Let Neeladri Das Sujit K. Ghosh 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2023,135(1):e202214095
In case of pollutant segregation, fast mass diffusion is a fundamental criterion in order to achieve improved performance. The rapid mass transport through porous materials can be achieved by availing large open pores followed by easy and complete accessibility of functional sites. Inducing macroporosity into such materials could serve as ideal solution providing access to large macropores that offer unhindered transport of analyte and full exposure to interactive sites. Moreover, the challenge to configure the ionic-functionality with macroporosity could emerge as an unparalleled avenue toward pollutants separation. Herein, we strategized a synthetic protocol for construction of a positively charged hierarchically-porous ordered interconnected macro-structure of organic framework where the size and number of macropores can easily be tuned. The ordered macropores with strong electrostatic interaction synergistically exhibited ultrafast removal efficiency towards various toxic pollutants. 相似文献
85.
A. T. Soldatenkov A. W. Temesgen K. B. Polyanskii I. A. Bekro S. A. Soldatova A. A. Pupov N. D. Sergeeva 《Chemistry of Heterocyclic Compounds》2001,37(7):844-849
One-reactor oxidation by potassium permanganate has been carried out for a series of 4-aryl- and 4-methyl-1,2,3,6-tetrahydropyridines to give 1-formylamino-substituted 3-arylpropan-3-ones and butan-3-ones. The effect has been studied of the nature of the substrate, the temperature, and interphase transfer catalysts on the yield of amino alkanone. It is proposed that the reaction proceeds through the intermediate formation of 3,4-dihydroxypiperidin-2-ones which then undergo oxidative decyclization with elimination of one carbon atom. 相似文献
86.
对高能激光大气传输非线性问题的数值模拟进行了计算方法的研究。用快速富里叶变换法和分量分离法进行了理论分析和数值对比计算,两种方法都达到二阶精度,分量分离法计算稳定性比较好,运算速度快。 相似文献
87.
Dr. Letícia F. Sosa Dr. Priscilla M. de Souza Dr. Raphaela A. Rafael Dr. Robert Wojcieszak Dr. Eric Marceau Prof. Dr. Sébastien Paul Dr. Valérie Briois Prof. Dr. Fabio B. Noronha Prof. Dr. Fabio S. Toniolo 《ChemCatChem》2024,16(2):e202300890
The hydrodeoxygenation of furfural (FF) over Mo carbides in liquid phase at 200 °C, 30 bar of H2 for 4 h in 2-butanol was investigated. Unsupported and SiO2-supported Mo carbide with different crystallographic phases (β-Mo2C/SiO2 and α-MoC/SiO2), and in the presence of Cu and Ni as promoters were studied. The reactivation treatment under H2 atmosphere of the passivated Mo carbides was investigated by XAS. The results show that Mo is present in different states of oxidation in the passivated catalysts, with more severe oxidation in the bimetallic systems, in which the original carbides are not restored after reactivation. Finally, the product distribution in the HDO of furfural is modified as a function of catalyst oxidation degree. Using the less oxidized Mo carbide (β-Mo2C), a higher yield to 2-methylfuran is obtained, while C10 condensation products are formed for the more oxidized catalysts. 相似文献
88.
de Lima Melchiades Gabriela Angeli Valéria Weiss Colombo Mariana Koester Letícia Scherer 《Journal of Thermal Analysis and Calorimetry》2020,142(3):1249-1260
Journal of Thermal Analysis and Calorimetry - Compatibility is an important step in pre-formulation studies during the development of solid dosage forms. In the present study, we used thermal... 相似文献
89.
Franciele Queiroz Ames Lívia Bracht Francielle Sato Lidiane Vizioli de Castro-Hoshino Bruno Ambrósio da Rocha Letícia Aparecida de Oliveira 《Natural product research》2020,34(16):2341-2345
Abstract Fish oil (FO) is a natural source of omega-3 fatty acids, with well-established beneficial effects in inflammatory diseases when FO is orally administered. This study investigated the effects of a topically applied FO preparation (FOP) on phenol-induced ear edema and evaluated the percutaneous penetration of FOP in ear tissue. After applying phenol, groups of mice received FOP on the ear. After 1?h, ear tissue was collected to determine the percent inhibition of edema, myeloperoxidase activity, and to perform photoacoustic spectroscopy (PAS). Treatment with FOP did not reduce edema, but reduced myeloperoxidase activity. The FOP decreased the area of bands that characterize inflamed tissue and penetrated into the tissue. These results indicated an inhibitory effect of FOP on leukocyte recruitment in phenol-induced ear edema. These data support the applicability of PAS as a non-destructive method for evaluating the inflammatory response, percutaneous penetration and antiinflammatory activity of compounds. 相似文献
90.
Dr. Kelly A. D. F. Castro Letícia D. Costa Juliana A. Prandini Dr. Juliana C. Biazzotto Prof. Dr. Augusto C. Tomé Prof. Dr. Michael R. Hamblin Prof. Dr. Maria da Graça P. M. S. Neves Prof. Dr. M. Amparo F. Faustino Prof. Dr. Roberto S. da Silva 《Chemistry (Weinheim an der Bergstrasse, Germany)》2021,27(6):1990-1994
Photodynamic therapy (PDT) is a promising alternative to overcome the resistance of melanoma to conventional therapies. Currently applied photosensitizers (PS) are often based on tetrapyrrolic macrocycles like porphyrins. Unfortunately, in some cases the use of this type of derivative is limited due to their poor solubility in the biological environment. Feasible approaches to surpass this drawback are based on lipid formulations. Besides that, and inspired in the efficacy of potassium iodide (KI) for antimicrobial photodynamic therapy (aPDT), the combined effect of singlet oxygen (1O2) with KI was assessed in this work, as an alternative strategy to potentiate the effect of PDT against resistant melanoma cells. 相似文献