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61.
S. V. Shishkina S. M. Desenko K. G. Nazarenko O. V. Shishkin 《Journal of Structural Chemistry》2005,46(1):191-194
X-ray diffraction investigation showed that protonation of 4H-benzo-[1,4]-oxazin-3-ylidene-cyclohexylamine occurs at the exocyclic nitrogen atom. In crystal, the cation has a structure with a distinct exocyclic C=N bond. 相似文献
62.
T. A. Volovnenko A. V. Tarasov R. I. Zubatyuk O. V. Shishkin A. V. Turov Yu. M. Volovenko 《Chemistry of Heterocyclic Compounds》2009,45(12):1489-1502
The interaction of 2-chloroquinoline-3-carbaldehydes with 1H-benzimidazol-2-ylacetonitriles and 1-benzyl-1H-imidazol-2-ylacetonitrile
has been studied. It was shown that products of condensation at the methylene group are formed under mild conditions. Carrying
out the reaction under more forcing conditions leads to an intramolecular nucleophilic substitution of the chlorine atom and
the formation of cyclic ionic compounds (in the case of N-substituted hetarylacetonitriles), which are subsequently dealkylated. 相似文献
63.
D. V. Shishkin N. Z. Baibulatova A. N. Lobov S. P. Ivanov L. V. Spirikhin V. A. Dokichev 《Chemistry of Natural Compounds》2010,46(1):62-65
Diastereomers of N(12)-(2-hydroxy-2-phenylethyl)cytisine were synthesized by reduction of N(12)-(2-oxo-2-phenylethyl)cytisine
by Yamamoto reagent. Their structures were solved using x-ray structure analysis. 相似文献
64.
Oleg V. Shishkin Irina V. Omelchenko Andrei L. Kalyuzhny Boris V. Paponov 《Structural chemistry》2010,21(5):1005-1011
Results of X-ray diffraction study and quantum-chemical calculations revealed that molecular conformation of thioindirubin
molecule creates suitable conditions for formation of intramolecular C–H···O and S···O interactions. Analysis of molecular
electrostatic potential (MEP) demonstrates existence of two areas of positive MEP (σ-holes) in the outermost part of the sulfur
atom on the continuation of the lines of the C–S bonds. One of these σ-holes is oriented toward region of negative MEP around
the oxygen atom of carbonyl group. Such situation corresponds to formation of σ-hole or chalcogen bond. Existence of both
types of bonding interactions is confirmed by topological analysis of electron density distribution using “Atoms in Molecules”
(AIM) theory. Energies of the C–H···O hydrogen bond and the S···O σ-hole bond derived from AIM and NBO theories are very close. 相似文献
65.
Lipson V. V. Svetlichnaya N. V. Borodina V. V. Shirobokova M. G. Shishkina S. V. Shishkin O. V. Musatov V. I. 《Russian Journal of Organic Chemistry》2010,46(9):1388-1398
Three-component condensation of 5(3)-amino-3(5)-methylpyrazole with aromatic aldehydes and 1,3-cyclohexanedione afforded mixtures
of 3-methyl-4-aryl-2,4,6,7,8,9-hexa hydro-5H-pyrazolo[3,4-b]quinolin-5-ones and 2-methyl-9-aryl-5,6,7,9-tetrahydro pyrazolo[5,1-b]quinazolin-8(4H)-ones. The reaction of 3-aminopyrazolo-4-carbonitrile and ethyl 3-aminopyrazolo-4-carboxylate with aldehydes and cyclo hexanedione
or dimedome is regioselective and leads to the formation of partially hydrogenated pyrazolo [5,1-b]quinazolin-8-one systems.
In all compounds the dihydroazine ring exists in the enamine tautomeric form. 相似文献
66.
V. G. Pleshchev N. V. Baranov D. A. Shishkin A. V. Korolev A. D. Gorlov 《Physics of the Solid State》2011,53(10):2054-2060
It has been shown that intercalation of the HfSe2 compound with chromium atoms results in an increase in the magnetic susceptibility and a decrease in the resistivity while retaining the semiconductor conductivity type. The Cr x HfSe2 compounds exhibit a paramagnetic behavior at temperatures above 2 K in the entire concentration range 0 ≤ x ≤ 0.25. It has been revealed that an increase in the electron density due to additional introduction of copper can cause the appearance of a cluster-spin-glass-type state in Cr x Cu y HfSe2 compounds. The data obtained indicate a large role of the indirect exchange interaction via conduction electrons in the formation of the magnetic state in layered intercalated compounds based on transition metal dichalcogenides. 相似文献
67.
K. I. Pashkevich D. V. Sevenard O. G. Khomutov O. V. Shishkin E. V. Solomovich 《Russian Chemical Bulletin》1999,48(2):359-363
2-Polyfluoroacylcyclohexanones react with semicarbazide and thiosemicarbazide to give 2-(thio)carbamoyl-3-hydroxy-3-polyfluoroalkyl-3,3a,4,5,6,7-hexahydro-2H-indazoles, one of which was studied by X-ray diffraction.
Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 2, pp. 361–365, February, 1999. 相似文献
68.
69.
Shishkin D. V. Baibulatova N. Z. Dokichev V. A. 《Russian Journal of Organic Chemistry》2009,45(12):1879-1880
Russian Journal of Organic Chemistry - 相似文献