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31.
5-Alkyl(aryl)-3-arylidene-3H-pyrrolin-2-ones were synthesized by ammonolysis of their O-heteroanalogs or by the reactions of 5-alkyl(aryl)-3H-pyrrolin-2-ones with aromatic aldehydes. The structures of the compounds obtained were confirmed by 1H NMR spectra. 相似文献
32.
Ahmed M. M. Gabr Hoda B. Mabrok Emam A. Abdel-Rahim Mohamed K. El-Bahr Iryna Smetanska 《Natural product research》2018,32(15):1867-1871
Hairy root culture is a promising alternative method for the production of secondary metabolites. In this study, transformed root of Linum usitatissimum was established using Agrobacterium rhizogenes A4 strain from root cultures for lignans, phenolic acids and antioxidant capacity determination. Total lignin content (secoisolariciresinol diglucoside, secoisolariciresinol and matairesinol) was 55.5% higher in transformed root cultures than in the non-transformed root culture. Secoisolariciresinol was detected in higher concentration (2.107 μmol/g DM) in the transformed root culture than non-transformed culture (1.099 μmol/g DM). Secoisolariciresinol diglucoside and matairesinol were exclusively detected in the transformed root culture, but were not found in the non-transformed root culture. The overall production of phenolic acids in transformed roots was approximately 3.5 times higher than that of the corresponding non-transformed culture. Free radical scavenging DPPH˙ and ABTS˙+ assays showed 2.9-fold and 1.76-fold higher anti-oxidant activity in transformed root culture as compared to non-transformed. 相似文献
33.
Sharutin V. V. Pakusina A. P. Egorova I. V. Platonova T. P. Bukvetskii B. V. Popov D. Yu. 《Russian Journal of Coordination Chemistry》2002,28(12):827-830
Tetraphenylantimony nitrite was synthesized by reacting pentaphenylantimony with triphenylantimony dinitrite at a molar ratio of 1 : 1 in toluene, and its structure was determined using X-ray diffraction analysis. The Sb atom is coordinated to the oxygen atom of the axial nitrite group to form a trigonal bipyramid. The Sb–C(Ph)eq distances vary within the 2.103–2.111(3) Å range, and the S–O(1) and Sb–C(41) bond lengths are equal to 2.386(3) and 2.156(3) Å, respectively. The Sb...N distance and the axial C(41)SbO(1) angle are equal to 3.133(4) Å and 174.7(1)°, respectively. 相似文献
34.
Luminescence properties of Tb(III) and Eu(III) complexes of quinolonecarboxylic acid derivatives were studied. Optimal conditions
of luminescence were determined, and the influence of surfactants and diethylenetriaminepentaacetic acid on the luminescence
properties of the complexes was studied. It was demonstrated that species-specific immunoglobulins labeled with terbium ions
can be determined with the detection limit of the lanthanide label 5 x 10-14 M. 相似文献
35.
Oxygen reduction reaction (ORR) is one of the most technologically relevant reactions. It occurs at the interface of the electrocatalyst and electrolyte, where oxygen reacts with protons and electrons to produce water. Because the electrocatalyst is dispersed on a high surface area support, morphological confinement becomes critical, as it dictates proton and oxygen transport. Furthermore, confinement is induced by ionomer, ionic liquids (ILs), or molecular additives, and their impact on electrocatalyst reactivity and transport properties is currently not well understood. We present an overview of electrostatics and mass transport–induced confinement and zoom in into ILs and molecular additives and try to unravel how local confinement induced by them impacts ORR. 相似文献
36.
37.
V. A. Sedavkina V. A. Morozova A. Yu. Egorova R. G. Savkin 《Russian Chemical Bulletin》1995,44(10):1914-1916
Treatment of 5-alkyl-3H-furan-2-ones and 5-alkyl-3H-thiophen-2-ones with dichlorocarbene under conditions of phase-transfer catalysis at 20–90 °C results in insertion of the carbene at the C=C bond followed by skeletal rearrangement.Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 10, pp. 1995–1997, October, 1995. 相似文献
38.
Ryashentseva M. A. Egorova E. V. Trusov A. I. Antonyuk S. N. 《Russian Chemical Bulletin》2002,51(9):1698-1701
The activity and selectivity of mono- and bimetallic catalysts containing copper and rhenium on sibunite were studied in the decomposition of methanol to methyl formate (MF), water, H2, CO, and CO2at 200—400 °C. Methane is also formed on rhenium-containing catalysts at 300—400 °C. The dehydrogenating activity and selectivity to form MF are higher on the copper-sibunite catalysts than on the rhenium-sibunite samples. The introduction of 0.25% Re into the 4% copper-containing catalyst enhances its total activity and stability. 相似文献
39.
Sharutin V. V. Sharutina O. K. Egorova I. V. Pavlushkina I. I. Pushilin M. A. Gerasimenko A. V. 《Russian Journal of Coordination Chemistry》2004,30(1):23-26
A reaction of triphenylbismuth with 2,4,6-tribromophenol and hydrogen peroxide (molar ratio 1 : 2 : 1) in ether affords triphenylbismuth bis(2,4,6-tribromophenoxide). The complex obtained was structurally characterized by X-ray diffraction analysis. The coordination polyhedron of the Bi atom is a trigonal bipyramid with axial aroxy groups. The Bi–C and Bi–O bond lengths are 2.202(4), 2.203(4), 2.212(4) and 2.241(3), 2.245(3) Å, respectively. The intramolecular Bi···Br(1,4) contacts are 3.629(1) and 4.077(1) Å, respectively. 相似文献
40.
V. V. Sharutin I. V. Egorova O. K. Sharutina O. A. Dorofeeva T. K. Ivanenko A. V. Gerasimenko M. A. Pushilin 《Russian Journal of Coordination Chemistry》2004,30(12):874-883
The reactions of tetraphenylbismuthonium and -stibonium salts Ph4EX (E = Bi, Sb; X = I, OSO2 (C6H3(CH3)2-2,5), OSO2C6H3(OH-4)(COOH-3)) with bismuth triiodide in acetone afford complexes [Ph4Bi]+[PhBi(C5H5N)I3]-, [(Ph4BiO)2S(O){2,5-(CH3)2C6H3S(O)} [Ph2Bi2I6]2–, [Ph4Sb [Bi4I16]4-·2(CH3)2C=O, and [Ph4Sb] 3+ + [Bi5I18]3-, whose structural units, according to the X-ray diffraction data, are tetraphenylbismuthonium (-stibonium) cations and mono-, di-, tetra-, and pentanuclear anions, respectively. 相似文献