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21.
22.
The reactions of chloromethylsilanes with amines, hexamethyldisilazane, and silylcarbamates were studied. The dependence of the composition and structure of the resulting products on the nature of the reagents used and reaction conditions was determined. A scheme for the synthesis of 4,9-diaza-2,7-dioxa-1,6-disilacyclodecane-3,8-dione derivatives was suggested.Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 10, pp. 1798–1801, October, 1994. 相似文献
23.
24.
N. N. Zemlyanskii I. V. Borisova A. K. Shestakova Yu. A. Ustynyuk E. A. Chernyshev 《Russian Chemical Bulletin》1998,47(3):469-474
The first stable dibenzosilafulvene, 9-{[8-(dimethylaminomethyl)-1-naphthyl]phenylsil-1-ylium}fluoren-9-ide (7a), was obtained in one step from 9-fluorenyllithium and chloro[8-(dimethylaminomethyl)-1-naphthyl]phenylsilane as a stable
solvate with THF. The structure of the zwitterionic compound7a was established by1H,13C, and29Si NMR in solution and in the solid state. The reactions of compound7a with crotonaldehyde, ethanol, and triethylethylidenephosphorane are described. The data on the synthesis of alkoxy- and alkylthiochloro-9-fluorenylsilanes
and their phosphonium salts are given.
Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 3, pp. 486–491, March, 1998. 相似文献
25.
N. N. Aleinikov G. K. Vasil'ev S. A. Kashtanov E. F. Makarov Yu. A. Chernyshev 《Russian Chemical Bulletin》1996,45(6):1344-1349
The of photochemical decomposition of XcO4 under the action of UV-radia(ion in the wavelength range of 200–300 nm was investigated. The quantum yield of the formation of oxygen atoms upon XeO4 photodissociation was measured (Ф = 3.6±0.4). The results obtained point to the predominant role of the XeO4 +hv → 4O + Xe photodissociation channel of XeO4. The value of the rate constant of the reaction XeO4 + O → O2 + XeO3 was estimated (<4.5 · 10?16 cm2 s?1). 相似文献
26.
A. I. Chernyshev V. S. Kartashov A. P. Arzamastsev S. E. Esipov P. L. Senov S. M. Nevashin 《Chemistry of Natural Compounds》1980,16(5):500-507
On the basis of the results of a study of the dependence of the chemical shifts of the signals in the13C NMR spectra of neomycin B, monomycin A, and kanamycin A, over a wide pH range (from 1.0 to 10.0) a complete assignment of
the spectra signals of these antibiotics has been made. Optimum pH values of solutions are proposed for which the more complete
resolution of the resonance signals in the spectra of neomycin B, monomycin A, and kanamycin A is observed.
All-Union Scientific-Research Institute of Antibiotics, Moscow. I. M. Sechenov 1st Moscow Medical Institute. Translated from
Khimiya Prirodnykh Soedinenii, No. 5, pp. 686–695, September–October, 1980. 相似文献
27.
28.
A geometrical method is suggested for representing a molecule by a smoothed region. The effective volume and surface area are calculated, which results in more adequate proportionality of interactant molecules compared to the classical van der Waals models. 相似文献
29.
L. G. Voskressensky T. N. Borisova T. A. Vorob’eva A. I. Chernyshev A. V. Varlamov 《Russian Chemical Bulletin》2005,54(11):2594-2601
Reactions of substituted tetrahydropyrrolo[3,2-c]pyridines with dimethyl acetylenedicarboxylate in protic and aprotic solvents were studied. A novel single-step method for
the synthesis of pyrrolo[2,3-d]azocine derivatives was developed.
Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 11, pp. 2513–2519, November, 2005. 相似文献
30.
I. V. Ukrainets N. L. Bereznyakova G. P. Petyunin I. A. Tugaibei V. B. Rybakov V. V. Chernyshev A. V. Turov 《Chemistry of Heterocyclic Compounds》2007,43(6):729-739
An improved method for the preparation and purification of ethyl 2-hydroxy-4-oxo-4H-pyrido[1,2-a]-pyrimidine-3-carboxylates
is proposed. According to 1H and 13C NMR spectroscopic data the synthesized compounds exist in DMSO solution in the 2-hydroxy-4-oxo form while in the crystal
(at least for the case of the unsubstituted derivative) X-ray analysis shows that it occurs in the bipolar 2,4-dioxo form.
__________
Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 6, pp. 864–876, June, 2007. 相似文献