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21.
22.
[reaction: see text] Enantioselective total syntheses of belactosin A, belactosin C, and its homoanalogue have been accomplished in high overall yields (32% for belactosin A from the amino acid 10, and 35 and 36% for belactosin C and its homoanalogue, respectively). This concise approach comprises a novel sequential acylation/beta-lactonization reaction and allows a facile alteration of the substituents, thus providing a flexible route to a new family of highly active belactosin-based proteasome inhibitors. 相似文献
23.
R. F. Klevtsova L. A. Glinskaya T. E. Kokina S. V. Larionov 《Journal of Structural Chemistry》2003,44(2):256-267
Single crystals of [Ni(Phen)(iBu2PS2)2] (I) and [Ni(Phen)3](iBu2PS2)2 (III) compounds were grown, and their structures were determined by Xray diffraction analysis (CAD4 diffractometer, MoK
radiation, 3336 F
hkl
, R = 0.0373 for I and 2575 F
hkl
for III). The crystals of complex I have a triclinic unit cell with the following parameters: a = 11.097(1) , b = 14.903(2) , c = 22.650(3); = 75.18(1)°, = 80.50(1)°, = 75.07(1)°, V = 3479.2(7)3, Z = 4, calc = 1.255 g/cm3, and space group
1; the crystals of III have a monoclinic unit cell with the following parameters: a = 19.010(3), b = 15.481(1) , c = 17.940(3); = 97.58(1)°, V = 5233.5(12)3, Z = 4, calc = 1.292 g/cm3, and space group C2/c. The structure of complex I is built from mononuclear molecules, and the structure of III, from [Ni(Phen)3]2+ complex cations and i Bu2PS2
- outersphere anions. The NiN2S4 coordination polyhedra in the structure of I and NiN6 in the structure of III are distorted octahedra. Based on structural data, the interaction between the coordinated Phen molecules of complexes I, [Ni(Phen)2(iBu2PS2)](iBu2PS2) (II), and III is considered, as well as the packing modes of these complexes. 相似文献
24.
S. V. Larionov L. I. Myachina Z. A. Savel’eva L. A. Glinskaya R. F. Klevtsova L. A. Sheludyakova A. V. Tkachev S. N. Bizyaev 《Russian Journal of Coordination Chemistry》2004,30(12):837-845
New optically active levorotatory compounds [Ni(HL1)]NO3 (I) and [Ni(HL2)]NO3H2O (II) containing the anions of chiral diaminodioximes, H2L1 and H2L2, derived from the terpenes ±-pinene and (+)-3-carene, respectively, were synthesized. Complexes I and II were studied by X-ray diffraction. The crystal structures of compounds are ionic, being composed of the [Ni(HL1)]+ or [Ni(HL2)]+ cations and the outer-sphere NO3– anions. The Ni2+ ion coordinates four N atoms of the tetradentate chelating ligand, the NiN4 coordination unit being shaped like a tetrahedrally distorted square. Compounds I and II are diamagnetic, which corresponds to a low-spin d8 configuration. The NMR spectra of compounds were recorded and analyzed.Translated from Koordinatsionnaya Khimiya, Vol. 30, No. 12, 2004, pp. 888–896.Original Russian Text Copyright © 2004 by Larionov, Myachina, Saveleva, Glinskaya, Klevtsova, Sheludyakova, Tkachev, Bizyaev. 相似文献
25.
V. N. Kirichenko A. B. Uvaricheva S. V. Larionov L. A. Vishnevetskaya L. B. Volodarskii 《Russian Chemical Bulletin》1989,38(11):2416-2418
Complexes of Ni2+ and Co3+ with the deprotonated anions of the new ligand N-(3-oximino-2,4-dimethylpentyl-2)hydroxylamine are prepared. The compounds synthesized sublime in vacuum. 相似文献
26.
Larionov S. V. Leonova T. G. Glinskaya L. A. Klevtsova R. F. Platonov V. E. Maksimov A. M. Fadeeva V. P. Batrachenko N. I. 《Russian Journal of Coordination Chemistry》2000,26(12):861-865
Compounds (CH3)2Sn(C12F9S)2 (I), (CH3)2Sn(C10F7S)2 (II), and (C2H5)2Sn(C10F7S)2 (III) were synthesized. Single crystals of Iwere grown and structurally characterized using X-ray diffraction analysis (1590 reflections, R = 0.0209). The crystals are orthorhombic, a = 40.848(8) Å, b = 6.058(1) Å, c = 11.183(2) Å, V = 2767(1) Å3, (calcd.) = 2.024 g/cm3, space group Pbcn, Z = 4. The structure is built from monomeric molecules. The coordination polyhedron of the Sn atom (the SnC2S2 core) is a distorted tetrahedron. Compounds I–III are volatile when heated in vacuo. Thermolysis of these compounds results in SnO2 (in air) or SnS2 (in argon). 相似文献
27.
T. E. Kokina L. A. Glinskaya A. M. Agafontsev E. V. Artimonova L. A. Sheludyakova I. V. Korol’kov A. V. Tkachev S. V. Larionov 《Russian Chemical Bulletin》2013,62(12):2595-2602
3-(2-Methoxyphenylamino)caran-4-one and 2-(2-methoxyphenylamino)pinan-3-one E-oximes obtained from appropriate natural terpenes were transformed into 1: 1 complexes with PdCl2. The structures of the complexes were examined by X-ray diffraction. 相似文献
28.
V. B. Larionov V. S. Fedorova 《Moscow University Computational Mathematics and Cybernetics》2012,36(1):36-40
We consider the structure and basic properties of a superlattice of a class of homogeneous functions of k-valued logic for any k ≥ 2. 相似文献
29.
T. E. Kokina A. V. Tkachev L. I. Myachina S. N. Bizyaev L. A. Sheludyakova L. A. Glinskaya I. V. Korol’kov E. G. Boguslavskii S. V. Larionov 《Russian Journal of General Chemistry》2013,83(2):336-347
Coordination compounds Pd2(H2L2)Cl4 (I), Cu2(H2L2)Cl4 (II), Pd2(H2L3)Cl4 (III), and Cu2(H2L3)Cl4 (IV), where H2L2 and H2L3 are chiral bis-α-aminooxime ligands consisting of (+)-3-carene or (+)-limonene fragments and 4,4′-methylenedianiline linker, were synthesized and examined by NMR, ESR, and IR spectroscopy. The structure of [Cu(i-PrOH)CL2(μ-H2L3)CuCL2·H2O] (V) was determined by X-ray analysis. 相似文献
30.
We report on the results of measurement of the coefficients of hydrogen diffusion through metal membranes in the course of their simultaneous hydrogen saturation and bombardment with electrons (energy 30 keV, current density from 3 to 30 µA/cm2) both in a broad and in a narrow beam. It is found that the time of hydrogen discharge from the membrane is determined by the parameters of the electron beam, its periodicity and duration, and also depends on the structure of the phase state of the metal membrane. It is shown that the diffusion coefficient increases when a narrow electron beam in the scanning regime is used. Analysis of the hydrogen yield as a function of time is carried out on a mass spectrometer connected to a vacuum chamber containing an electron gun, a beam sweep oscillator, and an electrolytic cell. The hydrogen diffusion coefficients under the action of a scanning electron beam are 15 times larger than under the same conditions without irradiation. 相似文献