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1.
The circular dichroism (CD) method has been used to study the stereochemistry of the bisbenzyltetrahydroisoquinoline alkaloids. A relationship has been established between the absolute configurations of the asymmetric centers and the parameters of the Cotton effects in the CD spectra. The changes in the CD spectra on protonation have been correlated with conformational rearrangements of the molecules due to the different attachment of the oxygen bridges.Institute of the Chemistry of Plant Substances, Academy of Sciences of the Uzbek SSR, Tashkent. Translated from Khimiya Prirodnykh Soedinenii, No. 6, pp. 818–823, November–December, 1979. 相似文献
2.
I. V. Moiseeva P. M. Lukin O. E. Nasakin V. N. Romanov V. A. Tafeenko A. Kh. Bulai P. A. Sharbatyan 《Chemistry of Heterocyclic Compounds》1992,28(2):237-237
Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 2, p. 282, February, 1992. 相似文献
3.
Orlov I. S. Moiseeva A. A. Butin E. P. Egorov M. P. 《Russian Chemical Bulletin》2002,51(10):1961-1962
An unusual reaction of diaminogermylene and diaminostannylene with sterically hindered phenols which leads to the formation of stable phenoxyl radicals in high concentrations was found. The reaction mechanism was proposed. Amides [(Me3Si)2N]2E (E = Ge, Sn) were investigated electrochemically. 相似文献
4.
G. P. Moiseeva Sh. Z. Kasymov M. R. Yagudaev G. P. Sidyakin 《Chemistry of Natural Compounds》1980,16(3):254-256
It has been shown that it is possible to use the method of circular dichroism to determine the absolute configuration of the asymmetric center at C11 in the eudesmanolides. The orientations of the hydroxy group at C1 and of the methyl group at C4 in arabsin have been established.Institute of the Chemistry of Plant Substances, Academy of Sciences of the Uzbek SSR, Tashkent. Translated from Khimiya Prirodnykh Soedinenii, No. 3, pp. 343–346, May–June, 1980. 相似文献
5.
I. P. Nazarova A. I. Glushenkova N. T. Ul'chenko G. P. Moiseeva 《Chemistry of Natural Compounds》1989,25(1):54-57
A study has been made of the gossypol pigments of the seeds and roots of a cotton plant of the variety Tashkent-1 infected with wilt in comparison with a healthy plant. The amount of gossypol in the infected plant was lower than in the healthy plant. In the diseased plant, gossypurpurin was concentrated in the roots, and in the healthy plant it was concentrated in the seeds. Gossypol possessing optical activity was detected in the seeds and roots of both the healthy and the diseased plants.Institute of the Chemistry of Plant Substances, Uzbek SSR Academy of Sciences, Tashkent. Translated from Khimiya Prirodnykh Soedinenii, No. 1, pp. 63–66, January–February, 1989. 相似文献
6.
7.
Gekhman A. E. Amelichkina G. E. Moiseeva N. I. Vargaftik M. N. Moiseev I. I. 《Kinetics and Catalysis》2001,42(4):496-505
Anthracene and its alkyl derivatives undergo oxidation in the V(V)/H2O2/AcOH system via a nonradical mechanism through the intermediate formation of the vanadium(V) complex with singlet dioxygen as a ligand. The 1O2molecule is transferred from this complex to an unsaturated substrate. The free singlet dioxygen 1O2(1
g
) is almost inactive toward anthracene in AcOH solution. Consequently, the vanadium(V) complex with singlet dioxygen is the only oxidant species active in the reaction. The ratio between the rate constant of the reaction of this complex with 2-ethylanthracene and the rate constant of its deactivation is an order of magnitude greater than the ratio between the rate constant of the reaction of dissolved free singlet dioxygen with the same substrate and the rate constant of its deactivation (physical quenching). 相似文献
8.
Shmyreva Zh. V. Moiseeva L. V. Ponomareva L. F. Zelenskaya Yu. E. Dolgova T. Yu. 《Russian Journal of Applied Chemistry》2003,76(11):1862-1863
Effect of transition metal (Mn, Fe, Co, Ni, Cu, Zn) diketonates on oxidation of sunflower-seed oil with atmospheric oxygen was studied. 相似文献
9.
10.
K. P. Butin A. A. Moiseeva T. V. Magdesieva E. V. Sergeeva V. I. Rozenberg V. G. Kharitonov 《Russian Chemical Bulletin》1994,43(5):783-789
The potentials of electrochemical oxidation (
) and reduction (
) of monobromo- and isomeric di- and tribromo[2.2]paracyclophanes as well as
of mono-, di-, and tribromobenzenes were measured in acetonitrile. The similarity between the properties ofpseudo-para-disubstituted cyclophanes andmeta-disubstituted benzenes, on the one hand, andpseudo-meta-disubstituted cyclophanes andpara-disubstituted benzenes, on the other hand, was confirmed by the existence of a linear relationship between
of bromo-substituted [2.2]paracyclophanes and
of the corresponding bromo-substituted benzenes. The results were explained in terms of the qualitative theory of molecular orbitals, taking into account a through space interaction between the -systems of the benzene rings.Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 5, pp. 839–845, May, 1994.The authors wish to express their gratitude to Professor R. Hoffmann (Cornell University, USA) for a useful discussion and criticisms of the text of this paper.This work was financially supported by the Russian Foundation for Basic Research (Project 93-03-5246). 相似文献