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1.
M. G. Voronkov N. N. Vlasova O. Yu. Grigor’eva Yu. N. Pozhidaev S. A. Bol’shakova 《Russian Journal of General Chemistry》2005,75(7):1091-1093
Condensation of (aminomethyl)triethoxysilane with thiocarbamide in the presence of catalytic amounts of ammonium sulfate was used to synthesize N,N-bis(triethoxysilylmethyl)thiocarbamide. The latter was brought into oxidative hydrolytic polycondensation with H2O2 to obtain poly[N,N′-bis(silsesquioxanylmethyl)thiocarbamide S, S-dioxide] whose properties were compared with the properties of poly[N,N′-bis(silsesquioxanylpropyl)thiocarbamide S,S-dioxide]. Both polymers in highly acidic media rather strongly absorb Ag(I), while at pH 7 they reduce most absorbed Ag+ to the metal. Their reaction with potassium permanganate involves reduction of Mn7+ to Mn4+. The first polymer is a less effective sorbent and redox agent than the second.__________Translated from Zhurnal Obshchei Khimii, Vol. 75, No. 7, 2005, pp. 1154–1156.Original Russian Text Copyright © 2005 by Voronkov, Vlasova, Grigor’eva, Pozhidaev, Bol’shakova. 相似文献
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M. G. Koroleva O. V. Dyablo A. F. Pozharskii E. V. Sennikova Z. A. Starikova 《Russian Journal of Organic Chemistry》2005,41(7):997-1004
The corresponding N-nitroso derivatives were synthesized by the action of nitrous acid on N,N,N′-trimethylnaphthalene-1,8-diamine, N,N,N′-trimethyl-5-nitronaphthalene-1,8-diamine, and N,N,N′-trimethylacenaphthene-5,6-diamine, and molecular structure of the products was studied.__________Translated from Zhurnal Organicheskoi Khimii, Vol. 41, No. 7, 2005, pp. 1020–1027.Original Russian Text Copyright © 2005 by Koroleva, Dyablo, Pozharskii, Sennikova, Starikova. 相似文献
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The geometries of N,N′-diphenylbenzene-1,4-diamine (DPPD), N-phenyl-N′-(1-phenylethyl)benzene-1,4-diamine (SPPD), N-(4-methylpentan-2-yl)-N′-phenylbenzene-1,4-diamine (6PPD), N-propan-2-yl-N′-phenylbenzene-1,4-diamine (IPPD), N-(2-methoxybenzyl)-N′-phenylbenzene-1,4-diamine (MBPPD), and N-phenyl-N′-(2-phenylpropan-2-yl)benzene-1,4-diamine (CPPD) as well as of their dehydrogenation products were optimized by the semiempirical
AM1 method. The results support the idea of stable NB=CX structures formation during the consecutive dehydrogenation of SPPD, 6PPD, IPPD, and MBPPD antioxidants. The biradicals formed
during the second step of dehydrogenation of substituted phenylenediamines might be important for their antioxidant effectiveness.
Dedicated to Professor Vladimír Kvasnička, DrSc., in honour of his 65th birthday 相似文献
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M. Grin’ko V. Kulcitki N. Ungur A. Barba K. Delyanu P. F. Vlad 《Chemistry of Natural Compounds》2007,43(3):277-281
Several α,ω-bifunctional derivatives of E,E,E-geranylgeraniol were prepared via convergent synthesis starting with geraniol (8), which was converted in three steps into the tetrahydropyranyl ether of 8-chlorogeraniol (9) and 8-hydroxygeranylphenylsulfone (10). Combination of synthons 9 and 10 with subsequent reductive removal of the phenylsulfonyl group produced the tetrahydropyranyl ether of ω-hydroxygeranylgeraniol (5), hydrolysis of which gave exclusively trans-ω-hydroxygeranylgeraniol (1). Derivatives 5–7 of geranylgeraniol were synthesized using standard methods.
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Translated from Khimiya Prirodnykh Soedinenii, No. 3, pp. 231–234, May–June, 2007. 相似文献
7.
I. V. Kulakov 《Chemistry of Natural Compounds》2009,45(4):522-524
Condensation of the monosaccharides D-glucose and D-galactose with synthesized halo-substituted p-phenylenediamines and 4-amino-2,6-dibromophenol was studied. It was found that glycosylation occurred only at the 4-amino
group that was sterically unhindered by the halogen atom. The position of the aglycon in the glycoside was established by
PMR spectroscopy. 相似文献
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Reactions of barbituric, 1,3-dimethylbarbituric, and 2-thiobarbituric acids with 2-(1-pyrrolidinyl)benzaldehyde, its 6- and 7-membered homologs, and 4-phenylpiperazine and morpholine analogs lead to formation of fused systems with a spirocyclic 2,4,6-trioxopyrimidine fragment. The process involves intermediate formation of labile 5-arylmethylidenebarbituric acids which exhibit t-amino effect and undergo spontaneous isomerization to give the final products. The observed spirocyclizations are characterized by an anomalously high rate.__________Translated from Zhurnal Organicheskoi Khimii, Vol. 41, No. 6, 2005, pp. 920–925.Original Russian Text Copyright © 2005 by Krasnov, Kartsev. 相似文献
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Anita Kovács I. Csóka Magdolna Kónya E. Csányi A. Fehér I. Erős 《Journal of Thermal Analysis and Calorimetry》2005,82(2):491-497
Summary The properties of the inner and the external aqueous phases, were studied in w/o/w multiple emulsions with light microscopic image analysis and differential scanning calorimetry (DSC). The importance of multiple
emulsions lies in the presence of these aqueous phases, making them available for sustained, controlled drug delivery systems.
Differentiation of these two aqueous phases, studying the effect of manufacturing technology on droplet structure, quantitative
determination of phase volumes and any changes occurring during storage are essential when planning w/o/w emulsions. The present study uses microscopic observations combined with DSC measurements in order to identify the formed
structure, at developmental stage in case of different components, preparation methods, and stirring rates. These tools are
beneficial during manufacturing as in process controls, or to ensure product quality. 相似文献
14.
A. D. Dubonosov V. P. Rybalkin Ya. Yu. Vorob’eva V. A. Bren’ V. I. Minkin S. M. Aldoshin V. V. Tkachev A. V. Tsukanov 《Russian Chemical Bulletin》2004,53(10):2248-2252
It was shown by electron absorption spectroscopy and X-ray diffraction analysis that steric strains in photochromic 2-(N-acyl-N-arylaminomethylene) benzo[b]thiophen-3(2H)-one molecules ortho-substituted in the N-phenyl ring increase the quantum yield of the N→O photoinduced rearrangement in accord with an increase in the steric constant of the ortho-substituent.__________Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 10, pp. 2151–2155, October, 2004. 相似文献
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O. V. Kalyazina T. G. Murzabekova T. F. Lelyukh I. A. Gritskova 《Russian Chemical Bulletin》2007,56(3):535-539
Copolymers of the poly(N,N-dimethyl-N,N-diallylammonium chloride) macromonomer (1′) with acrylamide (2) with a high content of cationic groups (up to 50%) were synthesized. The relative activities r
1′ and r
2 were calculated. The relative activities calculated by the Kelen—Tudos (r
1′ = 0.057±0.009, r
2 = 1.57±0.12) and Feynman—Ross (r
1′ = 0.055±0.011, r
2 = 1.58±0.14) methods are in accordance. The intrinsic viscosity and the yield of copolymers were found to decrease with an
increase in the molar fraction of macromonomer 1′ in the monomer mixture.
Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 3, pp. 515–518, March, 2007. 相似文献
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Gold nanoparticles exhibit unique optical, thermal, chemical and physical properties. The microorganisms have high potential
for production of nanoparticles with wide applications. Application of fungi to produce nanoparticles is potentially exciting
because of their ability to secrete large amounts of enzymes. In this study, we investigated biosynthesis of gold nanoparticles
by the fungus Epicoccum nigrum isolated from Andalian gold mine in north-west of Iran. The gold nanoparticles were produced intra and extracellular by reaction
of an aqueous solution of chloroauric acid with the biomass of fungus E. nigrum. The produced gold nanoparticles were in the size range of 5–50 nm in spherical and rod shapes. This is the first report
on the biosynthesis of gold nanoparticles by the fungus E. nigrum. 相似文献
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M. Madesclaire V. P. Zaitsev J. V. Zaitseva S. Kh. Sharipova 《Chemistry of Heterocyclic Compounds》2007,43(10):1325-1332
A synthesis is reported for (4R,5R)-and (4S,5S)-4-hydroxymethyl-5-(4-nitrophenyl)oxazolidin-2-ones and (1′R,4R)-and (1′S,4S)-4-[hydroxy(4-nitrophenyl)methyl]oxazolidin-2-ones from (1R,2R)-and (1S,2S)-2-amino-1-(4-nitrophenyl)-1,3-propanediols. The effect of the experimental conditions on the formation of these compounds
was studied.
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Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 10, pp. 1562–1570, October, 2007. 相似文献
19.
2-Polyfluoroalkylchromene-4(4H)-thiones, synthesized from 2-polyfluoroalkylchromones and P2S5, react with aniline, phenylhydrazines, and hydroxylamine at the C(4) atom and afford corresponding anils, phenylhydrazones, and oximes of chromones. On heating in alcohol in the presence of concentrated HCl, chromone phenylhydrazones and oximes undergo ring closure to form 3-(2-hydroxyaryl)-1-phenyl-5-polyfluoroalkylpyrazoles and 5-hydroxy-3-(2-hydroxyaryl)-5-polyfluoroalkyl-Δ2-isoxazolines.__________Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 10, pp. 2188–2195, October, 2004. 相似文献