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61.
Fluoroalkyl -alkyl--aminovinyl ketones react with hydrazine hydrate to give the respective razoles and with phenylhydrazine they form a mixture of pyrazoles and 5 hydroxy-2-pyrazolines. Alkyl(aryl) -fluoroalkyl--aminovinylketones do not react with the hydrazines mentioned above. With 2,4-dinitrophenylhydrazine, both types of fluoroalkyl-containing -aminovinyl ketones give only hydrazones of the corresponding methyl alkyl(aryl) ketones. 相似文献
62.
V. V. Dovlatyan K. A. Éliazyan V. A. Pivazyan 《Chemistry of Heterocyclic Compounds》1997,33(12):1438-1440
Reaction of 2-N-potassiocyanamino-4,6-bisisopropyl(dimethylamino)-sym-triazines with acid 1,2,2,2-tetrachloroethylamides leads to the formation of 2-N-cyano-N-(1-acylamino-2,2,2-trichloroethyl)amino-4,6-bisisopropyl(dimethylamino)-sym-triazines. Reaction with 1-hydroxy(methoxy)-2,2,2-trichloroethylamides of chloroacetic acid leads to 2-(2-imino-4-oxooxazolidin-1-yl)-4,6-bis(dimethylamino)-sym-triazine and its 1-methoxy-2,2,2-trichloroethyl derivative substituted at the position 3 of the oxazolidine ring. 相似文献
63.
V. V. Dovlatyan K. A. Éliazyan S. M. Saakyan R. G. Mirzoyan 《Chemistry of Heterocyclic Compounds》1981,17(9):957-959
New 2-chloroethylthio derivatives of sym-triazine were obtained by the reaction of mercapto-sym-triazines and dichloroethane. It was established that these chlorides undergo cyclization to give 2-dialkylamino-4-oxo(thioxo)-4,5,6,7-tetrahydrothiazolo [1,2-a]-sym-triazines, the structure of which was confirmed by PMR and mass-spectral data, at moderate temperatures.See [7] for Communication 7.Translated f rom Khimiya Geterotsiklicheskikh Soedinenii, No. 9, pp. 1275–1278, September, 1981. 相似文献
64.
S. I. Dikhtyarev M. M. Yanina R. G. Kuznetsova B. I. Kurganov V. T. Chernobai 《Chemistry of Natural Compounds》1984,19(5):587-591
The enzyme urease has been isolated from the seeds of the watermelon of the Ogonek variety and has been characterized. The molecular weight of a rechromatographed sample of the enzyme has been determined as 480,000. The pH dependence of the activity of the urease and the kinetic parameters of the enzyme have been studied.All-Union Scientific-Research Institute of the Chemistry and Technology of Drugs, Khar'kov. Vitaminy Scientific-Production Amalgamation, Moscow. Translated from Khimiya Prirodnykh Soedinenii, No. 5, pp. 624–628, September–October, 1983. 相似文献
65.
N. A. Keiko Yu. A. Chuvashev T. A. Kuznetsova L. G. Stepanova L. I. Larina L. V. Sherstyannikova M. G. Voronkov 《Russian Chemical Bulletin》1998,47(7):1379-1381
Cyanosilylation of α-butylthioacrolein with trimethylsilyl cyanide occurs as 1,2-addition. Concurrent rapid dimerization of
α-butylthioacrolein occurred both in the presence and in the absence of H2PtCl6·6H2O as a catalyst to give 2,5-dibutylthio-2,3-dihydro-4H-pyran-2-carbaldehyde, whose cyanosilylation afforded the corresponding cyanohydrin. The latter is prone to retrodiene degradation
upon heating.
Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 7, pp. 1418–1420, July, 1998. 相似文献
66.
I. V. Sokolova O. N. Chaikovskaya V. A. Svetlichnyi R. T. Kuznetsova T. N. Kopylova G. V. Maier E. A. Sosnin E. A. Lipatov V. F. Tarasenko 《High Energy Chemistry》2002,36(4):272-275
The photolysis of aqueous solutions of two widespread environmental organic ecotoxicants—phenol and 4-chlorophenol—on excitation by UV radiation from a KrCl exciplex laser and a glow-discharge KrCl excilplex lamp was studied. The irradiated solutions were studied by spectroscopic techniques. The laser and lamp photolyses were compared. 相似文献
67.
V. V. Semenov V. S. Bogdanov B. S. Él'yanov L. G. Mel'nikova S. A. Shevelev V. M. Zhulin A. A. Fainzil'berg 《Chemistry of Heterocyclic Compounds》1982,18(8):859-864
The quaternization of 1- and 2-acetonyl-5-R-tetrazoles, as well as dimethyltetrazole, was accomplished under high pressure conditions (5000–14,000 kgf/cm2) by means of bromoacetone and methyl iodide and at atmospheric pressure and room temperature under the influence of methyl fluorosulfate. The structure of the salts were ascertained by 13C NMR spectroscopy, and the principles of the change in the chemical shifts and the spin-spin coupling constants during quaternization and protonation of the tetrazoles were studied.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 8, pp. 1118–1124, August, 1982. 相似文献
68.
M. E. Élyashberg Yu. Z. Karasev É. R. Martirosyan 《Journal of Structural Chemistry》1995,36(3):502-509
Major axioms underlying structure elucidation of molecules by their characteristic spectral data are considered. The amount
of information obtained by solving the problem on structure elucidation of molecules serves as a basis to evaluate the quality
of solution. Conditions for computer-aided solution of problems using expert systems (ES) are analyzed. Reasons for incorrect
or zero solutions and for inconsistencies leading to negative results are examined. The role of additional information as
a necessary condition for correct solution is discussed. On the basis of this analysis, a general strategy for structure elucidation
of molecules by their spectra using ES is suggested. The principal idea is to use the iteration method, gradually increasing
the rigidity of constraints. Strategies named ARCHEOLOGIST and SCULPTOR are discussed. Examples are given.
Russian Scientific Research Institute of Organic Synthesis. Translated fromZhurnal Strukturnoi Khimii, Vol. 36, No. 3, pp. 548–558, May–June, 1995.
Translated by L. Smolina 相似文献
69.
70.
S. V. Lindeman Yu. T. Struchkov M. N. Élinson S. K. Fedukovich G. I. Nikishin 《Journal of Structural Chemistry》1989,30(3):512-514
A. N. Nesmeyanov Institute of Heteroorganic Compounds, Academy of Sciences of the USSR. N. D. Zelinskii Institute of Organic Chemistry, Academy of Sciences of the USSR. Translated from Zhurnal Strukturnoi Khimii, Vol. 30, No. 3, pp. 171–173, May–June, 1989. 相似文献