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V. P. Andreev 《Russian Journal of Organic Chemistry》2009,45(7):1061-1069
Supernucleophilicity of pyridine N-oxides in acyl transfer reactions was rationalized for the first time on a theoretical level. Unlike pyridines, transition state derived from pyridine N-oxides is stabilized by direct conjugation between the nucleophilic and electrophilic components. 相似文献
3.
F. P. Sidel'kovskaya N. A. Mukhitdinova M. G. Zelenskaya V. A. Ponomarenko 《Chemistry of Heterocyclic Compounds》1968,4(2):159-160
N-(2,3-Epoxypropyl)-α-pyrrolidone and N-(2,3-epoxypropyl)-α-suecinimide have been obtained for the first time. It has been shown that N-(2,3-epoxypropyl)-α-pyrrolidone readily reacts with ammonia and diethylamine to form the corresponding amino alcohols. 相似文献
4.
V. V. Dovlatyan K. A. Eliazyan V. A. Pivazyan A. P. Yengoyan 《Chemistry of Heterocyclic Compounds》2008,44(8):991-995
2-Dimethylamino-4,6,7,8-tetrahydroimidazo[1,2-a]-sym-triazin-4-one synthesized by us previously is converted by the action
of aryl isocyanates and arenesulfonyl chlorides into the corresponding derivatives of urea and N-arenesulfonyl-substituted
imidazo-sym-triazinones. It was shown that 6-(2-chloroethoxy)-2-dimethylamino-4-(methoxycarbonylmethylamino)-sym-triazine
is converted by thermolysis into 2-dimethylamino-8-methoxycarbonylmethyl-4,6,7,8-tetrahydroimidazo[1,2-a]-1,3,5-triazin-4-one,
which is also obtained by the action of methyl bromoacetate on the imidazo-sym-triazinone.
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Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 8, pp. 1230–1235, August, 2008. 相似文献
5.
A number of (Z)-N,N-dialkyl- and (Z)-N-acyl-N-alkyl-O-methylnicotinamide oximes was synthesized. Their configuration was confirmed by the NOESY experiment. Evaluation of fungicidal
activity of compounds obtained was performed. 相似文献
6.
D. A. Köse G. Gökçe S. Gökçe İ. Uzun 《Journal of Thermal Analysis and Calorimetry》2009,95(1):247-251
Three novel mixed ligand complexes of Ni(II), Zn(II) and Cd(II) with p-chlorobenzote and N,N-diethylnicotinamide were synthesised and characterized on the basis of elemental analysis, FTIR spectroscopic
analysis, solid state UV-Vis spectrometric and magnetic susceptibility data. The thermal behavior of the complexes was studied
by simultaneous TG-DTA methods in static air atmosphere and the mass spectra data were recorded.
According to microanalytical results, formulas of complexes are C34H40N4O8ClNi, C34H40N4O8ClZn and C34H44N4O10ClCd. The complexes contain two moles of coordination waters, two moles p-chlorobenzoate and two mole N,N-diethylnicotinamide (dena) ligands per formula unit. In these complexes, the p-chlorobenzoate and N,N-diethylnicotinamide behave as monodentate ligand through acidic oxygen and nitrogen of pyridine ring.
The decomposition pathways and the stability of the complexes are interpreted in the terms of the structural data. The final
decomposition products were found to be as metal oxides. 相似文献
7.
T. F. Ibragimov M. G. Levkovich V. A. Saprykina Kh. M. Shakhidoyatov 《Chemistry of Natural Compounds》2010,46(5):767-770
N-Chloroacetylcytisine was synthesized by acylation of (–)-cytisine. Stable Z- and E-conformers with respect to rotational isomerism around the N-12–CO bond were found in PMR spectra at room temperature. The
point at which PMR resonances of the Z- and E-conformers coalesced upon heating was measured. The transition barrier between the conformers was estimated. 相似文献
8.
I. A. Kirilyuk D. A. Morozov Yu. S. Tabatchikova V. S. Medvedev A. V. Lebedev G. V. Romanenko T. V. Rybalova I. A. Grigor’ev 《Russian Chemical Bulletin》2008,57(7):1516-1533
The condensation of 3-hydroxyamino-3-methylbutan-2-one or 3-ethyl-3-hydroxyamino-pentan-2-one with aldehydes and ammonia afforded
a series of new 1-hydroxy-4-methyl-2,5-dihydroimidazoles, whose oxidation gave rise to the corresponding 5-methyl-4H-imidazole 3-oxides. The latter, like 1-hydroxy-4-methyl-2,5-dihydroimidazoles, react with PriONO in the presence of bases to form 4H-imidazole-5-carbaldoxime 3-oxides, which are transformed into 4H-imidazole-5-carbonitrile 3-oxides in the reaction with TsCl in the presence of Et3N. The by-products produced in different steps of the synthesis were isolated and characterized.
Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 7, pp. 1487–1503, July, 2008. 相似文献
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U. S. Makhmudov Sh. B. Rakhimov B. Tashkhodzhaev M. G. Levkovich V. I. Vinogradova 《Chemistry of Natural Compounds》2008,44(2):208-212
The molecular structures of N-(o-and p-hydroxybenzyl)cytisine were investigated by NMR spectroscopy, x-ray structure analysis, and molecular modeling. It was found
that NMR resonances of the OH and aromatic protons in N-(o-hydroxybenzyl)cytisine were doubled because of the presence of two conformers in solution.
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Translated from Khimiya Prirodnykh Soedinenii, No. 2, pp. 165–168, March–April, 2008. 相似文献
11.
O. G. Strukov V. B. Kondrat’ev Z. V. Vlasova V. A. Petrunin 《Russian Journal of Physical Chemistry A, Focus on Chemistry》2017,91(1):100-105
Conformers of the biologically active compounds CH3P(O)(OR)(SCH2CH2NR 2 ′ ), where (I) R = i-C4H9, R′ = C2H5 and (II) R = C2H5, R′ = i-C3H7, are calculated within the AM1 level of theory. The elongated and twisted forms with maximum and minimum distances between a nitrogen atom and those of a phosphorus tetrahedron, respectively, and bearing a syn and anti oriented alkoxy group relative to a phosphoryl oxygen, are studied. It is found that the differences between the energy, electronic, and geometric parameters of these forms are apparent in differences between their properties, e.g., the ability to participate in complexation and protonation, reactions that to some extent simulate the interaction between a substance and a biological object. 相似文献
12.
Previously unknown E isomers of azomethines (Schiff bases) were synthesized from vanillal and vanillin esters by their reaction with cyclohexylamine. 相似文献
13.
(S)-Asparagine and (S)-glutamine ortho-carboranyl derivatives with free amino and carboxy groups in the α-position were synthesized. By an example of N γ-(1,2-dicarba-closo-dodecarboran-3-yl)-(S)-glutamine it was demonstrated that the developed synthetic approach carboranyl derivatives of amino acids allowed the preparation of optically pure isomers. 相似文献
14.
Yu. A. Gubarev N. Sh. Lebedeva V. P. Andreev Ya. P. Nizhnik A. I. V’yugin 《Russian Journal of General Chemistry》2007,77(6):1093-1099
Thermooxidative decomposition of pyridine N-oxide, 4-(4-dimethylaminostyryl)pyridine N-oxide, 4-(4-methoxystyryl)pyridine N-oxide, quinoline N-oxide, 2-methylquinoline N-oxide, 4-chloroquinoline N-oxide, 2-styrylquinoline N-oxide, and 2-(4-dimethylaminostyryl)quinoline N-oxide was studied. The kinetic parameters of the thermooxidative processes were calculated according to three independent procedures. The relation between the nature of heterocyclic N-oxide and its stability to thermal oxidation was analyzed. 相似文献
15.
L. A. Mukhamedova T. M. Malyshko R. R. Shagidullin N. V. Teptina 《Chemistry of Heterocyclic Compounds》1968,4(1):1-4
The influence of the reaction conditions on the order of addition of alcohols and α-chloro ethers in an acid medium to dioxides of 1-vinyl-3-cyclohexene is described on the basis of a determination of the percentage content of the ratio of the isomers by IR spectroscopy. It has been established that under mild conditions the addition takes place selectively with the predominant opening of the oxide ring attached to the six-membered carbon ring. More severe conditions (higher temperature, smaller amount of solvent) favor the formation of isomers with an opened oxide ring on the ethylene grouping. 相似文献
16.
R. A. Khairullin M. B. Gazizov N. G. Aksenov A. Yu. Bandikova Yu. S. Kirillina 《Doklady Chemistry》2016,467(2):131-135
O,O-Dialkyl S-(1,1-dimethyl-2-oxoethyl) dithiophosphates, 2-(dialkoxythiophosphorylthio)-substituted aldehydes with branched carbon groups, were obtained by hydrolysis of phosphoryl-containing iminium salts. The reaction with primary amines results in imines containing acetal group in different positions. Tri- and tetra-substituted perhydro-1,3-diazoles and oxazoles containing a phosphorus atom in the side chain were prepared by reacting the aldehydes with O,Nand N,N-dinucleophiles. 相似文献
17.
A. V. Lezov G. E. Polushina A. A. Lezov P. S. Vlasov N. S. Domnina 《Polymer Science Series A》2011,53(2):93-101
The hydrodynamic and conformational properties of molecules of poly(N,N-diallyl-N,N-dimethylammonium chloride) and N,N-diallyl-N,N-dimethylammonium chloride-maleic acid copolymers of different compositions in solutions with various ionic-strength and pH
values, as well as of the polyelectrolyte complex based on the copolymer with dodecyl sulfate anions in chloroform, are studied.
For poly(N,N-diallyl-N,N-dimethylammonium chloride) molecules in a 1 M NaCl solution, the Kuhn segment length and the hydrodynamic diameter of the
chain are estimated as A = 3.9 nm and d = 0.48 nm, respectively. In acidic solutions with pH 3.5, the copolymers demonstrate behavior typical for polyelectrolytes.
In an alkaline solution with pH 13, when 1 M NaCl is added to the solution of the copolymer containing 29 mol % maleic acid
units, there is an antipolyelectrolyte effect that manifests itself as an increase in the intrinsic viscosity of the copolymer
and in the hydrodynamic radius of its molecules. It is found that an increase in the fraction of maleic acid units in the
copolymer from 12 to 42 mol % brings about a reduction in the equilibrium rigidity of its macromolecules from 4.1 to 2.2 nm.
The equilibrium rigidity of polyelectrolyte-complex molecules is higher than that of initial copolymer molecules owing to
steric interactions arising between the aliphatic chains of dodecyl sulfate anions. In an electric field, the molecules of
the complex are oriented owing to the induced dipole moment resulting from the displacement of dodecyl sulfate anions along
the chain contour. 相似文献
18.
R. N. Shakhmaev A. Sh. Sunagatullina D. A. Akimova V. V. Zorin 《Russian Journal of Organic Chemistry》2017,53(4):615-617
An efficient synthetic approach to 2E,4E and 2E,4Z isomers of ethyl 5-chloropenta-2,4-dienoate has been developed on the basis of one-pot oxidation–olefination of readily accessible (E)- and (Z)-3-chloroprop-2-en-1-ols by the action of barium manganate and ethyl (triphenyl-λ5-phosphanylidene)acetate. 相似文献
19.
Thermal investigations were performed on a colony of the Colombian stingless bee Trigona (Frieseomelitta) nigra paupera by means of thermometry and direct calorimetry.
A nest with about 2000 individuals was transferred to a twin calorimeter, where the bees continued their normal life and development.
Two camping boxes (‘Poor Man’s Calorimeter, PMC’) with Peltier elements as cooling systems were used as a differential system.
Each box had a volume of 8 L and a sensitivity of 19.2 mV W−1. The colony was monitored calorimetrically and thermometrically with resistors distributed in the nest. Signals were recorded
continuously by a four-channel data logger. 相似文献