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141.
Dynamic domain structures in the Anger state of iron garnet films are analyzed by a video micrographic technique. Data are
obtained on the evolution of individual spiral domains over the lifetime of each domain. A new mechanism for the destruction
of this state is discovered.
Pis’ma Zh. éksp. Teor. Fiz. 63, No. 6, 453–456 (25 March 1996) 相似文献
142.
The electron impact mass spectra of substituted 9-imino- and 9-oxotriazolo[1,5-a]pyrido[2,3-d]pyrimidines were studied. The mass spectral data obtained permitted us to determine the order of the fusion of the triazole, pyrimidine, and pyridine rings as well as the position of the hydrogen atoms at the heteroatoms. Compounds labelled with 15N and 13C atoms were used to check the assignments made.For Communication 3, see [1].Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 1, pp. 116–120, January, 1992. 相似文献
143.
Zyryanov V. A. Postovskii I. Ya. Nirenburg V. L. Rusinov V. L. 《Chemistry of Heterocyclic Compounds》1978,14(3):346-347
Chemistry of Heterocyclic Compounds - 相似文献
144.
D. N. Kozhevnikov A. M. Prokhorov V. L. Rusinov O. N. Chupakhin 《Chemistry of Heterocyclic Compounds》2004,40(7):911-915
The addition of CH-active compounds to 6-aryl-1,2,4-triazine 4-oxide is reversible and occurs under conditions of kinetic control at position 5 of the heterocycle to form cyclic C(5)-H adducts. Under conditions of thermodynamic control the nucleophilic attack is directed to position 3 of the heterocycle and is accompanied by its opening to form the more stable open chain addition products. Attack of ethylmagnesium bromide is directed exclusively to the 5 position of the 6-aryl-1,2,4-triazine 4-oxides as a result of the irreversibility of the given reaction. 相似文献
145.
V. L. Rusinov T. L. Pilicheva O. N. Chupakhin N. A. Klyuev D. T. Allakhverdieva 《Chemistry of Heterocyclic Compounds》1986,22(5):543-546
Condensation of diazoles with -dicarbonyl nitro compounds (nitromalondialdehyde and nitromalondiester) gives derivatives of azolo[5,1-c] [1,2,4]triazine with a nitro group in the triazine ring.For 4, see [1].Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 5, pp. 662–665, May, 1986. 相似文献
146.
E. G. Kovalev I. Ya. Postovskii G. L. Rusinov I. L. Shegal 《Chemistry of Heterocyclic Compounds》1981,17(11):1063-1076
The available data on the reaction of sym-tetrazines with various unsaturated compounds from 1958 to 1980 are systematized. The reaction of sym-tetrazines with alkenes, alkadienes, alkynes, and unsaturated carbocycles and heterocycles are presented.Deceased.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 11, pp. 1462–1478, November, 1981. 相似文献
147.
P. A. Slepukhin G. L. Rusinov S. S. Dedeneva V. N. Charushin 《Russian Chemical Bulletin》2007,56(2):345-350
The reactions of 8-chlorotetrazolo[1,5-a]pyrazine with N-, O-, and S-nucleophiles involve the ipso substitution of the chlorine atom. Heating of this compound with benzotriazole or phenyltetrazole results in elimination
of the nitrogen molecule from one of the tetrazole rings to form new annelated azapentalenes.
Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 2, pp. 334–338, February, 2007. 相似文献
148.
N. A. Klyuev R. A. Khmel'nitskii O. N. Chupakhin G. A. Mal'tseva V. L. Rusinov I. Ya. Postovskii 《Chemistry of Heterocyclic Compounds》1975,11(7):862-865
The high intensities of the molecular-ion peaks in the mass spectra of 9-phenylacridines, the absence of ions characterizing cleavage of the interannular bond, and the high selectivity of the fragmentation constitute evidence for the presence of conjugation between the aromatic rings of the system. Dehydrogenation processes during electron impact that lead to the formation of condensed systems are peculiar to the investigated compounds. Unique detachment of an amino group from the (M-H)+ ion was noted for 9-(4-aminophenyl)acridines. 相似文献
149.
E. G. Kovalev G. L. Rusinov G. G. Aleksandrov V. A. Anufriev E. O. Sidorov A. I. Chernyshev 《Chemistry of Heterocyclic Compounds》1991,27(11):1247-1252
The anhydro base of an N-methyllepidinium salt reacts with s-tetrazines to give spiro hetarenes with 4,5- and 1,4-dihydropyridazine structures. The regioselectivity of the cycloaddition was established. In addition to spiro annelation, intramolecular cyclization to give compounds with a carcass structure, for which x-ray diffraction analysis was carried out, occurs when s-tetrazines with -pyridyl substituents are used.See [1] for Communication 1.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 11, pp. 1545–1551, November, 1991. 相似文献
150.
I. A. Utepova A. E. Lakhina M. V. Varaksin I. S. Kovalev V. L. Rusinov P. A. Slepukhin M. I. Kodess O. N. Chupakhin 《Russian Chemical Bulletin》2008,57(10):2156-2161
Stable σH-adducts as intermediates of the nucleophilic substitution of hydrogen in 3-(2-pyridyl)-1,2,4-triazines were obtained for the first time using ferrocenyllithium as a nucleophilic reagent. The three-dimensional structures of the reaction products were established based on the X-ray diffraction study of 1-[4-ethyl-6-phenyl-3-(2-pyridyl)-5(H)-1,2,4-triazin-5-yl]ferrocene. 相似文献