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151.
B. S. Fedorov M. A. Fadeev A. A. Gidaspov E. A. Kosareva V. V. Bakharev 《Chemistry of Heterocyclic Compounds》2005,41(2):228-234
The aziridation of 2-R-4,6-bis(trinitromethyl)-1,3,5-triazines containing electron-donor substituents has been studied. It was found that the corresponding 4-azido-2-dialkylamino-6-trinitromethyl-1,3,5-triazines are formed when R = NMe2, NEt2. When R = O–NMe4
+ a novel reaction route was discovered leading to the tetramethylammonium salt of 5-polynitromethyltetrazolo[1,5-a]-1,3,5-triazin-7-one which is formed as a result of azido-tetrazole and lactim-lactam tautomeric conversion. Denitration of this salt at the trinitromethyl group occurs with retention of the tetrazolo-1,3,5-triazine structure. An X-ray analysis was carried out for the denitration product which was the dipotassium salt of 5-dinitromethyltetrazolo[1,5-a]-1,3,5-triazin-7-one.__________Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 2, pp. 259–266, February, 2005. 相似文献
152.
Zhaofei Li Junliang Sun Chun-K. Loong Fuhui Liao 《Journal of solid state chemistry》2005,178(11):3315-3322
A powder sample of Sr3FeMoO7 was synthesized by solid-state reaction in reduced atmosphere (5% H2/Ar). At room temperature, Sr3FeMoO7 crystallizes in a typical Ruddlesden-Popper (n=2) structure in the space group I4/mmm, and . The structure refinement indicates that the Fe and Mo ions are randomly distributed in a single B-site with small fraction of B-site and oxygen vacancies. At low temperature, long-range magnetic interaction was observed. The antiferromagnetic magnetic interaction can be described with a large unit cell, and cm=cn, in the magnetic space group An′. 相似文献
153.
154.
S. S. Shukurov M. A. Kukaniev I. M. Nasyrov K. S. Zakharo R. A. Karakhanov 《Russian Chemical Bulletin》1993,42(11):1874-1878
Reactions of 2-bromo-7-methyl-5-oxo-5H-1,3,4-thiadiazolo[3,2-a]pyrimidine with sodium derivatives of pentane-2,4-dione, malonodinitrile, Meldrum acid, acetoacetic, cyanoacetic and malonic esters have been shown to give the respective substituted derivatives. Azinyl-ylidene tautomerism has been found to be characteristic of these compounds, the latter existing mainly in the ylidene form. The acid hydrolysis of pentane-2, 5-dione and cyanoacetic and malonic esters derivatives has been investigated.Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 11, pp. 1957–1961, November, 1993 相似文献
155.
V. N. Britsun A. N. Esipenko V. V. Pirozhenko M. O. Lozinskii 《Chemistry of Heterocyclic Compounds》2005,41(10):1334-1338
We have established that the products of aminolysis of 2-aryl-5-R-5,6-dihydro-7H-[1,2,4]triazolo-[5,1-b][1,3]thiazin-7-ones
in boiling ethanol are 3-R-3-(5-aryl-4H-1,2,4-triazol-3-ylsulfanyl)-propanamides, and at 180°C–210°C (depending on the structure
of the substituent R): 3-phenyl-4,5-dihydro-1H-1,2,4-triazoline-5-thione and 3-arylacrylamides or 3-(3-aryl-5-thioxo-4,5-dihydro-1H-1,2,4-triazol-1-yl)propanamides.
__________
Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 10, pp. 1587–1592, October, 2005. 相似文献
156.
N. V. Gorbulenko T. M. Tkachuk T. V. Shokol V. V. Semeniuchenko A. V. Turov V. P. Khilya 《Chemistry of Heterocyclic Compounds》2007,43(5):569-575
The interaction has been studied of a series of substituted 3-hetaryl-7-hydroxychromones with amino acids and formaldehyde
(reactants ratio 1: 1: 2 respectively). In the case of glycine and Het = 3-isoxazolyl the product of aminomethylation at position
8 of the chromone was obtained, and with other Het (including Het = 4-phenyl-1,2,4-triazol-3-yl) 2-[6-alkyl-3-hetaryl-4-oxo-9,10-dihydro-4H,8H-chromeno[8,7-e][1,3]-oxazin-9-yl]acetic
acids were formed. With β-alanine and Het = 4-phenyl-1,2,4-triazol-3-yl the corresponding β-substituted propionic acid was
synthesized, but proline did not participate in the reaction, leading to bis(6-ethyl-3-hetaryl-7-hydroxychromon-8-yl)methane.
__________
Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 5, pp. 683–689, May, 2007. 相似文献
157.
Christopher M. Timperley Krystal E. Casey Stuart Notman David J. Sellers Nancy E. Williams Nichola H. Williams Gareth R. Williams 《Journal of fluorine chemistry》2006,127(12):1554-1563
Eighteen new fluorogenic analogues of organophosphorus nerve agents were synthesised and characterised. They included analogues of tabun, sarin, cyclosarin, soman, VX, and Russian VX, with the 7-oxy-4-methylcoumarin or 7-oxy-4-(trifluoromethyl)coumarin leaving group. These analogues inhibited acetylcholinesterase (AChE) effectively in vitro and therefore have potential as tools for the identification of novel organophosphatases in biological systems. Analogues of VX and Russian VX with the 7-amino-4-methylcoumarin group, although poor AChE inhibitors, may have utility for screening enzyme libraries for phosphoramidases capable of cleaving P-N bonds. 相似文献
158.
von Niessen Wolfgang Cederbaum Lorenz S. Kraemer Wolfgang P. 《Theoretical chemistry accounts》1977,44(1):85-93
The vertical valence ionization potentials of cyclopropane, ethylene oxide and ethylene imine are calculated by a many-body Green's function method. For C3H6 the ordering of the ionization potentials is 2e(), 1e(), 2a1(), 1a2(), 1e(). The assignment of the 2a1 and the 1a2 ionization potentials which has been controversial is thus clarified. The ordering is in agreement with the result obtained via Koopmans' theorem. For ethylene oxide and ethylene imine Koopmans' theorem fails in predicting the correct order of ionic states. For C2H4O the ordering of the ionization potentials is 2b
1(), 4a
1, 1a
2(), 2b
2,3a
1, 1b
1(), 1b
2, 2a
1 and for C2H5N 6a, 5a, 3a, 2a, 4a, 3a, 1a, 2a. The agreement of the computed ionization potentials with the experimental values is very satisfactory. 相似文献
159.
G. A. Gazieva A. N. Kravchenko Yu. A. Strelenko O. V. Lebedev R. G. Gaziev V. M. Zhulin 《Chemistry of Heterocyclic Compounds》2003,39(6):784-789
Acid hydrolysis and acetylation of 6,8-dialkyl-3-thia-2,4,6,8-tetraazabicyclo[3,3,0]octan-7-one 3,3-dioxides have been studied. 6,8-Dialkyl-3-thia-2,4,6,8-tetraazabicyclo[3,3,0]octan-7-one 3,3-dioxides disproportionate to 4,4'-sulfonyldiiminobis(1,3-dialkylimidazolidin-2-ones) and sulfamide when treated with acid at pH 1 or with acetyl chloride. The kinetics of the disproportionation have been studied. 相似文献
160.
用X_α方法对CH_4在Ni(Ⅲ)表面吸附解离反应的理论研究马晨生,马理,杨忠志(吉林大学理论化学研究所,长春,130023)关键词CH_4/Ni(Ⅲ)吸附体系,原子簇模型,CH_4/Mi_7,MS-X_α-SCF方法甲烷在Ni表面的催化重整反应在工业和国... 相似文献