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1.
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
2.
N. N. Sidamonidze R. O. Vardiashvili M. O. Isakadze E. I. Chachua 《Chemistry of Natural Compounds》2007,43(3):250-252
Addition of ethyl-, propyl-, and n-butylmercaptans to 1-O-allyl-2,3,4,6-tetra-O-acetyl-β-D-galactopyranose in the presence of benzoyl peroxide catalyst was studied for the first time. The products were 1-O-(3-ethylthiopropyl)-2,3,4,6-tetra-O-acetyl-β-D-galactopyranose, 1-O-(3-propylthiopropyl)-2,3,4,6-tetra-O-acetyl-β-D-galactopyranose, and 1-O-(3-butylthiopropyl)-2,3,4,6-tetra-O-acetyl-β-D-galactopyranose. Deacetylation of 1-O-(3-ethylthiopropyl)-2,3,4,6-tetra-O-acetyl-β-D-galactopyranose produced 1-O-(3-ethylthiopropyl)-β-D-galactopyranose.
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Translated from Khimiya Prirodnykh Soedinenii, No. 3, pp. 209–211, May–June, 2007. 相似文献
3.
The amount of water-soluble proteins in bud meristem of Larix sibirica L., Picea obovata L., and Abies sibirica L. was shown to increase by 2-3 times in autumn during development of low-temperature resistance. The fractional composition
of water-soluble proteins of the studied species and the amino-acid composition of groups of water-soluble proteins with different
molecular weight (MW) were similar. Nitrogen accumulated as aspartic acid, glycine, and alanine in high- and medium-molecular-weight
proteins. The peptides (MW < 5 kDa) typically had a high content of hydrophobic proline and hydrophilic tyrosine. 相似文献
4.
G. A. Abakumov V. K. Cherkasov T. N. Kocherova N. O. Druzhkov Yu. A. Kurskii M. P. Bubnov G. K. Fukin L. G. Abakumova 《Russian Chemical Bulletin》2007,56(9):1849-1856
New sterically hindered functionalized o-quinones were synthesized by the 1,4-nucleophilic addition of secondary cyclic amines to 3,6-di(tert-butyl)-o-benzoquinone. The ability of these o-quinones to form o-semiquinone complexes with transition and main-group metals was studied by ESR spectroscopy in solution.
Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 9, pp. 1786–1793, September, 2007. 相似文献
5.
V. V. Islamova N. A. Kucher V. I. Poltavtsev 《Russian Journal of Applied Chemistry》2009,82(8):1408-1412
We obtained an analytical solution of a problem of unsteady mass transfer under the equilibrium condition y = Ax + B to compare results with a problem solution in the case of equilibrium condition looking as y = Ax. 相似文献
6.
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.
Rolf W. Berg 《Monatshefte für Chemie / Chemical Monthly》2007,138(11):1045-1075
Summary. A review of the recent developments in the study and understanding of room temperature ionic liquids are given. An intimate
picture of how and why these liquids are not crystals at ambient conditions is attempted, based on evidence from crystallographical
results combined with vibrational spectroscopy and ab-initio molecular orbital calculations. A discussion is given, based mainly on some recent FT-Raman spectroscopic results on the model ionic liquid system of 1-butyl-3-methylimidazolium ([C4
mim][X]) salts. The rotational isomerism of the [C4
mim]+ cation is described: the presence of anti and gauche conformers that has been elucidated in remarkable papers by Hamaguchi et al. Such presence of a conformational equilibrium seems to be a general feature of the room temperature liquids. Then the “localized
structure features” that apparently exist in ionic liquids are described. It is hoped that the structural resolving power
of Raman spectroscopy will be appreciated by the reader. It is of remarkable use on crystals of known different conformations and
on the corresponding liquids, especially in combination with modern quantum mechanics calculations. It is hoped that these
interdisciplinary methods will be applied to many more systems in the future. A few examples will be discussed. 相似文献
8.
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
9.
I. A. Novakov V. V. Korolkov A. I. Pavlyuchko B. S. Orlinson L. A. Gribov 《Journal of Structural Chemistry》2004,45(4):563-569
An ab initio (6-31G**) study of binary associates of aniline and n-propylamine with nitrobenzene and m-cresol has been carried out. The structures corresponding to the total energy minimum of the system have been found for the associates, and their geometrical and energy characteristics have been determined. Basic types of intermolecular interactions have been established, and their effects on the reactivity of the amino group have been investigated.Original Russian Text Copyright © 2004 by I. A. Novakov, V. V. Korolkov, A. I. Pavlyuchko, B. S. Orlinson, and L. A. GribovTranslated from Zhurnal Strukturnoi Khimii, Vol. 45, No. 4, pp. 595–601, July–August, 2004.This revised version was published online in April 2005 with a corrected cover date. 相似文献
10.
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
11.
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
12.
Background
Arylamine N-acetyltransferases (NATs) are important drug- and carcinogen-metabolising enzymes that catalyse the transfer of an acetyl group from a donor, such as acetyl coenzyme A, to an aromatic or heterocyclic amine, hydrazine, hydrazide or N-hydroxylamine acceptor substrate. NATs are found in eukaryotes and prokaryotes, and they may also have an endogenous function in addition to drug metabolism. For example, NAT from Mycobacterium tuberculosis has been proposed to have a role in cell wall lipid biosynthesis, and is therefore of interest as a potential drug target. To date there have been no studies investigating the kinetic mechanism of a bacterial NAT enzyme. 相似文献13.
T. Kimura Y. Takahashi T. Kamiyama M. Fujisawa 《Journal of Thermal Analysis and Calorimetry》2007,88(2):587-595
Excess enthalpies (H
E)
of 17 binary mixtures of o- and m-isomers of dichlorobenzene, difluorobenzene, methoxymethylbenzene,
dimethylbenzene, dimethoxybenzene, aminofluorobenzene, fluoronitrobenzene,
diethylbenzene, chlorofluorobenzene, fluoroiodobenzene, bromofluorobenzene,
chloromethylbenzene, fluoromethylbenzene, bromomethylbenzene, iodomethylbenzene,
fluoromethoxybenzene, dibromobenzene at 298.15 K were measured. All excess
enthalpies measured were very small, and those of o-+m-isomers of aminofluorobenzene, dibromobenzene and
iodomethylbenzene were negative but 14 other binary mixtures of isomers were
positive over the whole range of mole fractions. H
E
of o-+m-isomers
of dimethoxybenzene showed the largest enthalpic instability and those of
aminofluorobenzene showed the largest enthalpic stability. There was a correlation
between dipole–dipole interaction, dipole–induced dipole interaction
or entropies of vaporization and excess partial molar enthalpies at infinite
dilution. 相似文献
14.
Pyridine N-oxide reacts with 2- and 3-aminopyridines and their N-p-tolylsulfonyl derivatives in alkaline medium in the presence of p-toluenesulfonyl chloride to give N-p-tolylsulfonyl-2,2′- and 2,3′-dipyridylamines, respectively, as a result of reductive acylamination. In the reactions with 4-aminopyridine and 4-p-tolylsulfonyl-aminopyridine, their N-p-tolylsulfonyl- and N,N-bis(p-tolylsulfonyl) derivatives are formed, while reductive acylamination does not occur.__________Translated from Zhurnal Organicheskoi Khimii, Vol. 41, No. 1, 2005, pp. 128–130.Original Russian Text Copyright © 2005 by Solekhova, Kurbatov. 相似文献
15.
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
16.
M. S. Al-Masri S. Mamish M. A. Al-Haleem K. Al-Shamali 《Journal of Radioanalytical and Nuclear Chemistry》2005,266(1):49-55
Summary Levels of 210Pb, 210Po, 137Cs and some trace elements (Cu, Zn and Pb) in two most common mosses (Lycopodium cernuum and Funaria hygrometrica) distributed in the eastern Mediterranean sea region (Syrian coastal mountains series) have been determined. Radiochemical analysis has shown that these plants contain high levels of 210Pb, 210Po, 137Cs. The highest concentration of 210Pb, 210Po and 137Cs were found to be 1450, 1322 and 1140 Bq . kg-1 dry wt. in L. cernuum, respectively. F. hygrometrica was found to have higher values of 210Pb and 210Po concentrations and reached 2392 and 2119 Bq . kg-1 dry wt., respectively. Correlation coefficients for radionuclide levels in both plants versus their levels in soil have been determined: No correlation for 137Cs for both plants has been observed. This indicates that 137Cs in these plants is of atmospheric origin and the plants can be used as deposition indicators. In addition, a correlation with radionuclide levels was found only for 210Pb and 210Po in F. hygrometrica samples and was mainly related to 226Ra content in soil and the existing faults, which are the main source of these radionuclides. On the other hand, lead concentration in L. cernuum was found to be in the range of 5-86.6 ppm, while F. hygrometrica samples were found to contain around 58 ppm. Both plants seem to accumulate lead from the atmosphere where vehicle emissions are the main source of lead in the region. Comparable concentrations of Cu and Zn were found in all plant and soil samples. 相似文献
17.
A. R. Jassbi M. Mehrdad M. Soleimani M. Mirzaeian A. Sonboli 《Chemistry of Natural Compounds》2005,41(4):415-417
Analyses of the essential oils of Bunium elegans (Fenzl) Freyn and B. caroides (Boiss.) Hausskn. ex Bornm., using GC, GC/MS, and13 C-NMR spectroscopy resulted in identification of their chemical constituents. The oils of both species contain mainly the
sesquiterpene hydrocarbons germacrene-D and E-caryophyllene, which amounted to 24.1% and 38% for B. elegans and 22.1% and 26.6% for B. caroides respectively. The oil of B. caroides contained the monoterpenes α-pinene and Z-β-ocimene in 4.1 and 5.9% respectively, while traces of monoterpenes were detected
for B. elegans. On the other hand, in B. caroides the phenylpropanoid derivatives asaricin (7.5%) and dillapiole (10.2%) were among the major constituents.
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Published in Khimiya Prirodnykh Soedinenii, No. 4, pp. 335–336, July–August, 2005. 相似文献
18.
N. S. Arutyunyan R. L. Nazaryan L. A. Akopyan G. A. Panosyan G. A. Gevorgyan 《Russian Journal of Organic Chemistry》2012,48(1):89-93
Reaction of 2,2-dimethyltetrahydro-2H-pyran-4-one with aqueous methanamine, followed by reduction of the Schiff base thus obtained with sodium tetrahydridoborate
gave N,2,2-trimethyltetrahydro-2H-pyran-4-amine which was subjected to cyanoethylation with acrylonitrile. The resulting 3-(2,2-dimethyltetrahydro-2H-pyran-4-ylmethylamino)propanenitrile was reduced with lithium tetrahydridoaluminate to N-(2,2-dimethyltetrahydro-2H-pyran-4-yl)-N-methylpropane-1,3-diamine, and some chemical transformations of the latter were studied. 相似文献
19.
P. A. Kikilo B. I. Khairutdinov Yu. G. Shtyrlin V. V. Klochkov E. N. Klimovitskii 《Russian Journal of Organic Chemistry》2005,41(7):1089-1092
3-Substituted 1H,5H-naphtho[1,8-ef][1,3]dithiocines (R = H, Me, Ph, t-Bu) were oxidized with m-chloroperoxybenzoic acid to the corresponding 2-oxides having trans configuration (R ≠ H). According to the 1H and 13C NMR data (including NOESY experiments), the disubstituted compounds at room temperature exist in a boat conformation with equatorial orientation of the substituent on C3 and oxygen atom on S2. The compound with no substituent on C3 gives rise to a mixture of boat conformers with axial and equatorial sulfoxide oxygen atoms at a ratio of 83:17.__________Translated from Zhurnal Organicheskoi Khimii, Vol. 41, No. 7, 2005, pp. 1109–1112.Original Russian Text Copyright © 2005 by Kikilo, Khairutdinov, Shtyrlin, Klochkov, Klimovitskii. 相似文献
20.
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