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21.
Ovchinnikova I. G. Valova M. S. Matochkina E. G. Kodess M. I. Tumashov A. A. Slepukhin P. A. Fedorova O. V. Rusinov G. L. Charushin V. N. 《Russian Chemical Bulletin》2011,60(5):965-974
A new type of intramolecular cyclization of 1,5-bis[2-(E-3-oxo-3-phenylprop-1-enyl)-phenoxy]-3-oxapentane with 3-aminotriazole promoted by potassium ions was discovered. A cascade
mechanism for the formation of crownophane with 4,7-dihydro[1,2,4]triazolo[1,5-a]-pyrimidine fragment was suggested. Effects of oligooxyethylene fragment of the chalcone podand and acid-base catalysis on
the selectivity of the cyclocondensation processes and degree of oxidation of triazolopyrimidine fragments were studied. The
product structures were confirmed by IR, 1H and 13C NMR spectroscopy and X-ray diffraction study. 相似文献
22.
I. G. Ovchinnikova D. K. Nikulov E. V. Bartashevich E. G. Matochkina M. I. Kodess P. A. Slepukhin A. V. Druzhinin O. V. Fedorova G. L. Rusinov V. N. Charushin 《Russian Chemical Bulletin》2011,60(5):824-840
Specific features of crystal packings and pre-organization of diarylideneacetonyl crownophane molecules to solid-phase photochemical
transformations were studied on the basis of X-ray diffraction data using methods of simulation of molecular crystal packings.
The tendency of the most part of the synthesized macrocyclic E,E-isomers to the formation of homochiral crystals (P212121) was revealed, while (23E,26E)-11,12,14,15-tetrahydro-8H-dinaphtho-[2,1-k:1′,2′-r][1,4,7,10]tetraoxacyclononadecine-23,26-dien-25(9H)-one is prone to polymorphism. A phenomenon of solid-phase stereospecific photochemical dimerization of molecules according
to the syn-head-to-tail type without crystal destruction (single crystal—single crystal transformation) was found for one of the modifications
of this crownophane. 相似文献
23.
A. S. Khokhlov E. M. Kleiner V. N. Bochkarev N. S. Ovchinnikova N. S. Vul'fson G. Yu. Pek V. F. Bystrov L. B. Senyavina 《Chemistry of Heterocyclic Compounds》1971,7(3):284-289
N4-Acylpenilloic acid lactam structures were assigned to the products of the reaction of penilloic acids with acid anhydrides on the basis of a chemical and physicochemical study.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 3, pp. 309–315, March, 1971. 相似文献
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V. G. Epshtein Z. V. Chernykh V. N. Ovchinnikova 《Mechanics of Composite Materials》1967,3(6):701-703
It is shown that the secondary structure of rubbers filled with carbon blacks can be expressed in terms of the volume of the relaxation kinetic element (V), calculated from the stress relaxation curves. The effect of the type and concentration of carbon black and the extension of the specimen on the quantity V has been investigated. The volume of the kinetic element decreases with increase in the concentration and dispersity of the carbon black. This is associated with an increase in the rubber-filler contact area, which causes the orientation of groups of molecular chains and reduces the size of the deformation unit. As the degree of extension of the specimen increases, V decreases.Mekhanika Polimerov, Vol. 3, No. 6, pp. 1066–1069, 1967 相似文献
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Kim Dmitry G. Kalita Elena V. Sharutin Vladimir V. Ovchinnikova Irina G. Ezhikova Marina А. Kodess Mikhail I. Slepukhin Pavel А. Vasilenko Anna V. 《Chemistry of Heterocyclic Compounds》2019,55(6):566-572
Chemistry of Heterocyclic Compounds - The sequence of condensation, alkylation, and halocyclization reactions during the synthesis of the target 2,3-dihydro[1,3]oxazolo[3,2-a]-pyridinium salts was... 相似文献
30.
Kim D. G. Petrova K. Yu. Frolova T. V. Sharutin V. V. Ovchinnikova I. G. Ezhikova M. A. Kodess M. I. 《Russian Journal of Organic Chemistry》2019,55(9):1333-1337
Russian Journal of Organic Chemistry - The reaction of N-allylthiourea with ethyl 2-ethyl-3-oxobutanoate gave 3-allyl-5-ethyl-6-methyl-2- thiouracil which reacted with bromine and iodine to afford... 相似文献