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11.
Cyclocondesation of 3-aryl(heteryl)pyrazole-4-carbaldehydes with ethyl acetoacetate and urea (thiourea) in the presence of FeCl3 · 6H2O afforded 3-aryl(heteryl)-4-(4-pyrazolyl)-1,2,3,4-tetrahydropyrimidin-2-ones(thiones).__________Translated from Zhurnal Organicheskoi Khimii, Vol. 41, No. 1, 2005, pp. 97–98.Original Russian Text Copyright © 2005 by Bratenko, Chornous, Vovk. 相似文献
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Annija Lace Aideen Byrne Simon Bluett Laurent Malaquin Vincent Raimbault Remi Courson Zain Hayat Breda Moore Eoin Murray 《Journal of separation science》2022,45(5):1042-1050
An ion chromatography system employing a low-cost three-dimensional printed absorbance detector for indirect ultraviolet detection towards portable phosphate analysis of environmental and industrial waters has been developed. The optical detection cell was fabricated using stereolithography three-dimensional printing of nanocomposite material. Chromatographic analysis and detection of phosphate were carried out using a CS5A 4 × 250 mm analytical column with indirect ultraviolet detection using a 255 nm light-emitting diode. Isocratic elution using a 0.6 mM potassium phthalate eluent combined with 1.44 mM sodium bicarbonate was employed at a flow rate of 0.75 mL/min. A linear calibration range of 0.5 to 30 mg/L PO43− applicable to environmental and wastewater analysis was achieved. For retention time and peak area repeatability, relative standard deviation values were 0.68 and 4.09%, respectively. Environmental and wastewater samples were analyzed with the optimized ion chromatography platform and the results were compared to values obtained by an accredited ion chromatograph. For the analysis of environmental samples, relative errors of <14 % were achieved. Recovery analysis was also carried out on both freshwater and wastewater samples and recovery results were within the acceptable range for water analysis using standard ion chromatography methods. 相似文献
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S. I. Orysyk V. V. Bon O. A. Zholob V. I. Pekhnyo V. V. Orysyk Yu. L. Zborovskii M. V. Vovk 《Russian Journal of Coordination Chemistry》2014,40(3):160-170
The syntheses and spectral (IR, UV-VIS, XPS, and 1H and 13C NMR) characteristics of the rhodium(III), palladium(II), and platinum(II) complexes with 2-(2-hydroxybenzoyl)-N-methylhydrazinecarbothioamide (HBMHCTA) are described. The coordination of HBMHCTA to the central metal ion and its intraligand rearrangement in the complex formation of rhodium(III) ions are studied. The structure of the mixed-ligand complex [Pd(H2L)PPh3] is determined by X-ray diffraction analysis. 相似文献
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I. V. Dyachenko R. I. Vas’kevich M. V. Vovk 《Russian Journal of Organic Chemistry》2014,50(2):263-270
2-[Allyl(propargyl)sulfanyl]pyrido[3,4-d]pyrimidin-4-ones at heating in polyphosphoric acid undergo an intramolecular cyclization with the formation of pyrido[4,3-e]thiazolo-[3,2-a]pyrimidin-5-ones of angular structure. Under similar conditions the cyclization of 2-(cinnamylsulfanyl)pyrido[3,4-d]-pyrimidin-4-one results in a linear pyrido[3′,4′:4,5]pyrimido-[2,1-b][1,3]thiazin-6-one. The iodocyclization of the same substrates affords the corresponding 9-(iodomethyl)(iodomethylidene)pyrido[4,3-e][1,3]thiazolo-[3,2-a]pyrimidin-5-ones and 3-iodopyrido[3′,4′:4,5]pyrimido[2,1-b][1,3]thiazin-6-one of angular structure. 9-(Iodomethyl)-8,9-dihydro-5H-pyrido[4,3-e][1,3]thiazolo[3,2-a]pyrimidin-5-one treated with sodium azide gave 9-(azidomethyl) derivative whose cyclization with substituted alkynes in the presence of copper compounds provided pyrido [4,3-e][1,3]thiazolo[3,2-a]pyrimidinylmethyltriazoles. 相似文献
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Ruslan I. Vaskevych Alla I. Vaskevych Eduard B. Rusanov Oksana Ya. Mel'nyk Mykhailo V. Vovk 《Journal of heterocyclic chemistry》2020,57(8):3202-3212
Selective iodocyclization of 6-(alkenylamino)-1-allylpyrazolo[3,4-d]pyrimidines provided hydrogenated derivatives of 1-allyl-8(9)-iodomethylimidazo(pyrimido)[1,2-a]pyrazolo[4,3-e]pyrimidines which were further reacted with NaN3 at 75°С to 80°С to give a series of new-type 1,3,6-triazocines annulated with the pyrazole, pyrimidine, imidazole (or pyrimidine), and 1,2,3-triazole rings. The compounds synthesized were structurally characterized by analytical, spectral (IR, 1H and 13C NMR, HPLC-mass), and X-ray diffraction data. 相似文献
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Russian Journal of Organic Chemistry - 相似文献
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T. V. Murzina E. M. Kim S. E. Matskevich O. A. Aktsipetrov A. F. Kravets A. Y. Vovk 《JETP Letters》2004,79(4):155-159
Magnetization-induced third harmonic (TH) generation was observed in magnetic nanostructures—nanogranular CoxAg1? x films—possessing giant magnetoresistance (GMR). The magnetization-induced contribution to the TH intensity was studied as a function of the concentration of a magnetic component (cobalt) in the films. Magnetic contrast of the TH intensity was found to correlate with the GMR coefficient: both parameters simultaneously reach extremum in the range of cobalt concentrations x~0.3–0.35. 相似文献
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V. A. Chornous A. N. Grozav D. V. Klyukovskii A. V. Bezdudnyi M. V. Vovk 《Russian Journal of Organic Chemistry》2013,49(4):568-574
The reduction of 1-aryl-4-chloro-1H-imidazole-5-carbaldehydes with sodium tetrahydridoborate gave 1-aryl-4-chloro-1H-imidazol-5-ylmethanols which were converted into 5-chloromethyl and 5-fluoromethyl derivatives. 1-Aryl-4-chloro-5-chloromethyl-1H-imidazoles reacted with sodium azide, secondary amines, thiols, and triphenylphosphine to produce the corresponding products of chlorine replacement in the 5-chloromethyl group. 相似文献