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81.
Chalykh A. E. Petrova T. F. Matveev V. V. Gerasimov V. K. Khasbiullin R. R. Shcherbina A. A. Abaturova N. A. 《Russian Chemical Bulletin》2020,69(4):675-682
Russian Chemical Bulletin - Phase equilibria in the mixtures of polyvinyl alcohol (PVA) and chitosan were revealed. Structures of the phases were identified. The temperature and concentration... 相似文献
82.
Faizullina L. Kh. Tagirov A. R. Salikhov Sh. M. Petrova S. F. Valeev F. A. 《Russian Journal of Organic Chemistry》2020,56(10):1840-1843
Russian Journal of Organic Chemistry - Michael adduct of levoglucosenone and cyclohexanone, 1,6-anhydro-3,4-dideoxy-4-C-(2-oxocyclohexan-1-yl)-β-D-erythrohexo-2-ulose, was treated with... 相似文献
83.
Petrova K. Yu. Kim D. G. Sharutin V. V. Zakharova D. M. 《Russian Journal of Organic Chemistry》2020,56(1):29-33
Russian Journal of Organic Chemistry - Alkylation of 5-allyl-6-methyl-2-thiouracil with benzyl chloride and allyl bromide afforded 2-benzyl(allyl)sulfanyl-5-allyl-6-methylpyrimidin-4(3H)-ones.... 相似文献
84.
Petrova A. V. Khusnutdinova E. F. Mustafin A. G. Kazakova O. B. 《Russian Journal of Organic Chemistry》2020,56(1):174-176
Russian Journal of Organic Chemistry - Mannich reaction of N-propargyl triterpene aldimines obtained from betulonic and oleanonic aldehydes gave new aminoalkyl derivatives containing an... 相似文献
85.
Maya M. Zaharieva Lyudmila L. Dimitrova Stanislav Philipov Ivanka Nikolova Neli Vilhelmova Petar Grozdanov Nadya Nikolova Milena Popova Vassya Bankova Spiro M. Konstantinov Dimitrina Zheleva-Dimitrova Hristo M. Najdenski 《Molecules (Basel, Switzerland)》2022,27(1)
This study evaluated the in vitro antineoplastic and antiviral potential and in vivo toxicity of twelve extracts with different polarity obtained from the herbaceous perennial plant Geum urbanum L. (Rosaceae). In vitro cytotoxicity was determined by ISO 10993-5/2009 on bladder cancer, (T-24 and BC-3C), liver carcinoma (HEP-G2) and normal embryonic kidney (HEK-293) cell lines. The antineoplastic activity was elucidated through assays of cell clonogenicity, apoptosis induction, nuclear factor kappa B p65 (NFκB p65) activation and total glutathione levels. Neutral red uptake study was applied for antiviral activity. The most promising G. urbanum extract was analyzed by UHPLC–HRMS. The acute in vivo toxicity analysis was carried out following OEDC 423. The ethyl acetate extract of aerial parts (EtOAc-AP) exhibited the strongest antineoplastic activity on bladder cancer cell lines (IC50 = 21.33–25.28 µg/mL) by inducing apoptosis and inhibiting NFκB p65 and cell clonogenicity. EtOAc and n-butanol extracts showed moderate antiviral activity against human adenovirus type 5 and human simplex virus type I. Seventy four secondary metabolites (gallic and ellagic acid derivatives, phenolic acids, flavonoids, etc.) were identified in EtOAc-AP by UHPLC–HRMS. This extract induced no signs of acute toxicity in liver and kidney specimens of H-albino mice in doses up to 210 mg/kg. In conclusion, our study contributes substantially to the detailed pharmacological characterization of G. urbanum, thus helping the development of health-promoting phytopreparations. 相似文献
86.
N. N. Tonkikh A. Strakovs K. V. Rizhanova M. V. Petrova 《Chemistry of Heterocyclic Compounds》2004,40(7):949-955
In reactions of 3-(5- and 5,6-substituted 2-aminophenylamino)-5,5-dimethylcyclohex-2-en-ones with carbaldehydes of pyridine, thiophene, and furan and substituted benzaldehydes, we have obtained 21 novel 7H-7-methoxycarbonyl-, 7-benzoyl-, 7-trifluoromethyl-, 7-nitro- and 7,8-dichloro-11-aryl-3,3-dimethyl-1,2,3,4,10,11-hexahydro-5H-dibenzo[b,e]-1,4-diazepin-1-one. 相似文献
87.
In reactions of 3-(2-amino-3-pyridyl)amino-5,5-dimethylcyclohex-2-en-1-one with aromatic aldehydes (2- and 4-hydroxy-, 2-hydroxy-3-methoxy-, 4-dimethylamino-, 4-methoxy-, 2,4- and 3,4-dimethoxy-, 3,4-methylenedioxy-, 4-bromo-, 4-fluoro-, 4-chloro-, 2-nitro- and 3-nitrobenzaldehydes, furfural, and 2-thiophenecarbaldehyde), we have obtained the corresponding 10-aryl-7,7-dimethyl-5,6,7,8,9,10-hexahydro-11H-pyrido[3,2-b][1,4]benzodiazepin-9-ones. 相似文献
88.
89.
E. V. Petrova 《Moscow University Physics Bulletin》2011,66(5):437-442
In situ investigation of the growth and dissolution of retgersite crystals α-NiSO4 · 6H2O in water-ethanol solutions (10–50 wt % of ethanol) was made by atomic force microscopy (AFM). The habit of crystals grown
in aqueous and water-ethanol solutions, as well as the Raman scattering spectra, were identical. It is shown that the typical
peak of sulphate ions at 981 cm−1 does not change after the addition of ethanol. Absorption spectra of aqueous and water-ethanol solutions also have similar
characteristic features. AFM images of hillocks on the (001) face of retgersite crystals were obtained directly in the process
of their growth. Using a series of distorted AFM images obtained in situ, a geometrical calculation scheme is given, which
allows one to recover the real direction of the growth steps. The kinetic coefficient of growth steps in aqueous and water-ethanol
solutions of retgersite is estimated. 相似文献
90.
In earlier work, a time-dependent, ionization dynamic model of a cluster of xenon atoms was constructed [2], [3] in an effort to determine conditions under which the X-ray line amplification data that was observed experimentally at wavelengths between 2.71 and 2.88 Å [1] could be replicated. Model calculations showed that, at laser intensities greater than 1019 W/cm2, the outermost N-shell electrons of xenon would be stripped away by tunnel ionization in less than a femtosecond. They also showed that L-shell electrons within the resulting cluster of Ni-like ions could be photoionized at a sufficient rate as to generate population inversions between these hole states and the states they radiatively decayed into. These inversions only lasted for several femtoseconds, and they were generated early in time when the cluster was being rapidly heated and the cluster's density was rapidly evolving, but was still high. They were seen to depend on the heating and expansion dynamics of the cluster, which had not been modeled in detail in this early work. In this paper, molecular dynamics calculations are described in which the rapidly evolving temperatures and ion densities of an intensely laser-heated cluster are calculated for different peak laser intensities and for two different sized xenon nano-clusters. This data is then used as an input to the ionization dynamic calculations in order to determine the influence of cluster size and of peak laser intensity on the gain coefficient calculations. In these calculations, inner-shell photoionization rates are shaped by the temperature and density dependence of the bremsstrahlung emissions under the assumption that these emissions drive the photoionizations. This shaping produces calculated gain coefficients that agree well with the measured ones. 相似文献