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1.
2.
T. V. Esipova A. A. Borisenko P. B. Terent’ev G. V. Grishina R. Herzshuh 《Russian Journal of Organic Chemistry》2006,42(5):742-747
A new class of endocyclic enamines, 1,6-disubstituted 1,2,3,4,5,6,7,8-octahydro-1,6-naphthiridines, was synthesized from 4-piperidone imines by successive subjecting the latter to lithiation with lithium diethylamide, to alkylation with 1-bromo-3-chloropropane, and to intramolecular cyclization. All stages were carried out as a unique process without isolation of the intermediate compounds. A thorough optimization of the process conditions, workup, and product storage was carried out. The conformational study of 1,6-disubstituted 1,2,3,4,5,6,7,8-octahydro-1,6-naphthiridines was performed. 相似文献
3.
It is proved that if the intrinsic zero-index of the Sasaki metric of a tangent bundleTM
n
isk, thenk is even andM
n
is the metric product of a Riemannian manifoldM
n–k/2 by a Euclidean spaceE
k/2, whileTM
n
is the metric product ofTM
n–k/2 byE
k
. An expression is obtained for the second fundamental forms of the imbeddingTF
l
TM
n
in terms of the second fundamental forms of the imbeddingF
l
M
n
and the curvature tensor ofM
n
. It is proved thatTF
l is totally geodesic inTM
n
if and only ifF
l
is totally geodesic inM
n
.Translated from Ukrainskií Geometricheskií Sbornik, Issue 28, 1985, pp. 12–32. 相似文献
4.
5.
M. M. Kabachnik Z. S. Novikova I. A. Chadnaya A. A. Borisenko I. P. Beletskaya 《Russian Chemical Bulletin》1998,47(2):332-339
A series of phosphorus(iii)-substituted azomethines and enamines were synthesized by the reaction of lithium salts of aldimines and ketimines with derivatives
of phosphorus(iii) acids. Some properties of the compounds synthesized were studied.
Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 2, pp. 339–346, February, 1998. 相似文献
6.
Normanskaja Yu. V. Borisenko O. D. Beloborodov I. B. Avetisyan A. I. 《Doklady Mathematics》2022,106(3):487-487
Doklady Mathematics - An Erratum to this paper has been published: https://doi.org/10.1134/S1064562422340038 相似文献
7.
8.
9.
At 20–70 °C, the temperature has almost no effect on the semisaturation field,B
1/2, or on the magnetic effects detected by exciplex fluorescence (pyrene/N,N-dimethylaniline) in binary benzene-DMSO mixtures. In individual solvents (ethanol, methanol) heating leads to a noticeable
increase in the magnetic effect, whileB
1/2 decreases. The results obtained corroborate a previously proposed hypothesis that polar microclusters are formed in binary
solvents with components of different polarity.
Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 10, pp. 1821–1823, October, 1993. 相似文献
10.
G. V. Grishina E. L. Gaidarova E. R. Luk'yanenko A. A. Borisenko 《Chemistry of Heterocyclic Compounds》1996,32(2):194-196
The stereochemistry of the asymmetric reduction of the imine obtained from 1,3-dimethylpiperidin-4-one and (S)--phenylethylamine has been studied. It is shown that hydride reduction of imine 1 by sodium borohydride in methanol is asymmetric and gives the cis and trans diastereomeric pair 1,3-dimethyl-4-(-phenyl-ethylamino) piperidine in the ratio 3:1. Using sodium in isopropanol gives only one trans diastereomeric pair.1H NMR has been used to identify the stereochemical structure and diastereomer excess of the cis and trans isomers of 1,3-dimethyl-4-(-phenylethylamino)piperidine which had been separated by column chromatography.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 2, pp. 219–221, February, 1996. 相似文献