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101.
Condensation of 2-chlorobenzaldehyde with cyanothioacetamide and ethyl butyroylacetate results in 4-(2-chlorophenyl)-3-cyano-5-ethoxycarbonyl-6-propyl-3,4-dihydropyridine-2(1H)-thione, whose further transformation affords the corresponding substituted 2-methylthio-1,4-dihydropyridine.
Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 1, pp. 173–175, January, 2000. 相似文献
102.
V. D. Dyachenko S. G. Krivokolysko V. P. Litvinov 《Chemistry of Heterocyclic Compounds》1997,33(11):1325-1327
3-Cyano-6-methyl-5-phenylcarbamoyl-3,4-dihydropyridinespiro-4-cyclohexane-2(1H)-thione was obtained by the condensation of
acetoacetic acid anilide with cyclohexylidenecyanothioacetamide. Substituted 2-alkylthio-1,4-dihydropyridines and 3-amino-2-(4-chlorobenzoyl)-6-methyl-5-phenylcarbamoyl-4,7-dihydrothieno[2,3-b]pyridinespiro-4-cyclohexane
were synthesized from it.
T. G. Shevchenko Lugansk State Pedagogical Institute, Lugansk 348011, Ukraine N. D. Zelinskii Institute of Organic Chemistry,
Russian Academy of Sciences, Moscow 117913. Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 11, pp. 1533–1535,
November, 1997. 相似文献
103.
S. G. Krivokolysko V. D. Dyachenko V. P. Litvinov 《Chemistry of Heterocyclic Compounds》1999,35(12):1441-1442
The condensation of acetaldehyde with cyanothioacetamide and ethyl benzoylacetate in the presence of N-methylmorpholine leads to the formation of 3-cyano-5-ethoxycarbonyl-4-methyl-6-phenylpyridine-2(1H)-thione. Alkylation of the last afforded the corresponding substituted 2-alkythiopyridines.T. G. Shevchenko Lugansk State Pedagogical Institute, Lugansk 348011, Ukraine. N. D. Zelinsky Institute of Organic Chemistry, Russian Academy of Sciences (RAN),Moscow 117913, Russia.Translated from Khimiya Geterotsklicheskh Soedinenii, No. 12, pp. 1645–1646, December, 1999. 相似文献
104.
105.
O. N. Kazheva G. V. Shilov O. A. Dyachenko M. A. Mekh V. I. Sorokin V. A. Ozeryanskii A. F. Pozharskii 《Russian Chemical Bulletin》2005,54(11):2492-2495
1-Dimethylamino-2,7-dimethoxy-8-methylamino-3,5-dinitronaphthalene and 1,2,4-tri-bromo-6-dimethylamino-5-methylaminoacenaphthylene
containing the N,N,N′-trimethyl-1,8-diaminonaphthalene fragment with the substituted aromatic ring were studied by X-ray diffraction. Both systems
are stabilized by an intramolecular hydrogen bond. The characteristics of the latter are determined by the influence of either
the ortho substituents or the peri-annelated five-membered ring. In the former case, the intramolecular hydrogen bond is substantially shortened (N...N, 2.628(5)
Å) due to the “buttressing effect” of the o-OMe groups, whereas the peri-dibromoethylene bridge and the Br substituent at position 4 cause a substantial elongation of the intramolecular hydrogen
bond (N...N, 2.75(2) and 2.76(1) Å) in the latter case.
Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 11, pp. 2414–2417, November, 2005. 相似文献
106.
The band structure of three-dimensional cubic approximants of a photonic quasicrystal has been determined by numerical calculation. The approximants of different orders appear to have large, almost isotropic, band gaps in a wide range of relative permittivity values. The existence of the complete band gap in the photonic quasicrystal with the six-dimensional bcc lattice is shown. 相似文献
107.
We study the long-time evolution of surface gravity waves on deep water excited by a stochastic external force concentrated in moderately small wave numbers. We numerically implemented the primitive Euler equations for the potential flow of an ideal fluid with free surface written in Hamiltonian canonical variables, using the expansion of the Hamiltonian in powers of nonlinearity of terms up to fourth order. We show that because of nonlinear interaction processes a stationary Fourier spectrum of a surface elevation close to <|eta(k)|(2)> approximately k(-7/2) is formed. The observed spectrum can be interpreted as a weak-turbulent Kolmogorov spectrum for a direct cascade of energy. 相似文献
108.
S. I. Lashkul A. B. Altukhov A. D. Gurchenko E. Z. Gusakov V. V. Dyachenko L. A. Esipov M. Yu. Kantor D. V. Kouprienko A. Yu. Stepanov A. P. Sharpjonok S. V. Shatalin E. O. Vekshina 《Czechoslovak Journal of Physics》2005,55(3):341-348
This paper deals with the new spectral and microturbulence experimental data and their analysis, which show that the radial electric field E
r generated at the lower hybrid heating (LHH) in the FT-2 is high enough to form the transport barriers. The ETB is formed when LHH is switched off. The radial fluctuation-induced E × B drift flux densities near LCFS in SOL are measured at two different poloidal angles. For this purpose two Langmuir probes located at low and high field sides of the torus are used. Registration of the poloidal and radial components of the electric field and density fluctuations at the same time during one discharge permits to measure the poloidal asymmetry of the transport reduction mechanism of the radial and poloidal particle fluxes in the SOL. The absolute
fluctuation levels show dependence on the sign of E
r shear. The modification of the microscale turbulence by the poloidal E
r × B rotation shear
E × B
at the L-H transition near LCFS is also studied by X-mode fluctuation reflectometry. The new data were obtained by spatial spectroscopic technique.Presented at the Workshop Electric Fields Structures and Relaxation in Edge Plasmas, Nice, France, October 26–27, 2004. 相似文献
109.
S. G. Krivokolysko V. D. Dyachenko A. N. Chernega V. P. Litvinov 《Chemistry of Heterocyclic Compounds》2001,37(10):1208-1215
The condensation of 2-chlorobenzaldehyde with cyanothioacetamide and 2-thenoyltrifluoroacetone in the presence of N-methylmorpholine takes place stereoselectively and leads to the formation of N-methylmorpholinium 4,5-trans-4-(2-chlorophenyl)-3-cyano-6-hydroxy-5-(2-thenoyl)-6-trifluoromethyl-1,4,5,6-tetrahydropyridine-2-thiolate. The latter was used to synthesize the corresponding 2-alkylthiotetrahydropyridines. The structure of 4,5-trans-4-(2-chlorophenyl)-3-cyano-6-hydroxy-2-methallylthio-5-(2-thenoyl)-6-trifluoromethyl-1,4,5,6-tetrahydropyridine was determined by X-ray crystallographic analysis. 相似文献
110.
Ya. Yu. Yakunin V. D. Dyachenko V. P. Litvinov 《Chemistry of Heterocyclic Compounds》2001,37(6):766-770
The reaction of ethoxymethylenacetylacetanilide with cyanothioacetamide or cyanoselenoacetamide in the presence of N-methylmorpholine and alkylating agents gave substituted 2-alkylthio- and 2-alkylselenopyridines and thieno[2,3-b]pyridines. 相似文献