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1.
B. T. Ibragimov S. A. Talipov T. F. Aripov 《Journal of inclusion phenomena and macrocyclic chemistry》1994,17(4):317-324
The structures of gossypol complexes are extremely sensitive to the halogenomethane present as the guest; e.g. changing the number of Cl atoms in chloromethane derivatives changes the structure of the gossypol complex. The crystals of C30H30O8·CH2Cl2 are monoclinic, space groupC2/c,a=21.320(4),b=19.199(6),c=15.765(2)Å, =113.05(2)o,V=5916(2)Å3,Z=8,D
x=1.35 g/cm3,T=295 K. The structure has been solved by direct methods and refined to the finalR value of 0.084 for 1828 reflections. In the structure H-bonded gossypol molecules form columns, generating channels in the structure which are filled by guest molecules. After decomposition (desolvation) monocrystals of the complexes are conserved without destruction, in which there are rather wide and empty channels though slightly smaller than in the complex. An attempt is made to explain some peculiarities of the behavior of the gossypol polymorph formed on the basis of its structure with empty channels.
Supplementary data relevant to this article have been deposited with the British Library Publication No. SUP 82165 (17 pages). 相似文献
2.
(R)-4-Menthenone in the synthesis of optically pure sex pheromone of the peach leafminer moth (Lyonetia clerkella) 总被引:1,自引:0,他引:1
Kharisov R. Ya. Latypova E. R. Talipov R. F. Muslukhov R. R. Ishmuratov G. Yu. Tolstikov G. A. 《Russian Chemical Bulletin》2003,52(10):2267-2269
The synthesis of (14S)-methyloctadec-1-ene, sex pheromone of the peach leafminer moth (Lyonetia clerkella), is described to demonstrate a new potential of the synthetic use of (R)-4-menthenone. 相似文献
3.
B. T. Ibragimov S. A. Talipov G. N. Tishchenko Yu. K. Kushmuradov T. F. Aripov S. Kuchkarov 《Chemistry of Natural Compounds》1982,17(6):546-551
The structure of tetrahydroneosophoramine has been studied by x-ray structural analysis. Rings A, B, and C have the chair conformation, and ring D the half-chair conformation. On the basis of a semiquantitative analysis it has been shown that the strains in the molecules of tetrahydroneosophoramine and of matrine are of the same order of magnitude.Institute of Bioorganic Chemistry, Academy of Sciences of the Uzbek SSR, Tashkent. Institute of Crystallography, Academy of Sciences of the USSR, Moscow. V. I. Lenin Tashkent State University. Translated from Khimiya Prirodnykh Soedinenii, No. 6, pp. 751–757, November–December, 1981. 相似文献
4.
M. Gdaniec B. T. Ibragimov S. A. Talipov 《Journal of inclusion phenomena and macrocyclic chemistry》1990,8(4):431-438
The crystal structure of the 2: 1 inclusion complex of gossypol with amyl acrylate has been determined by X-ray structure analysis. The crystals of (C30H30O8)2C8H14O2 are triclinic, space group P
,a = 14.425(2),b = 15.519(1),c = 16.409(2) Å, =97.89(1), = 117.80(1), =67.01(1)° (reduced cell:a = 14.425(2),b = 15.519(2),c = 16.017(2)Å, = 92.19(1), = 115.01(l), =67.01(1)°],V = 2986.7(5) Å3,Z = 2,D
x = 1.31 g cm–3, (CuK
) = 7.40 cm–1,T = 292 K. The structure has been solved by direct methods and refined to the final R value of 0.059 for 5155 observed reflections. The gossypol molecules bonded via several hydrogen bonds form centrosymmetric tetramers. The two independent gossypol molecules, A and B, are related within the tetramer by a local noncrystallographic 2-fold axis. The host molecules in the crystal form cavities in which two guest molecules are placed. The ester molecule interacts via a pair of C-...H-O hydrogen bonds with two gossypol molecules of the same chirality and belonging to the same tetramer unit. The amyloxy group of the ester molecule shows a very large thermal motion. It adopts a non-extended conformation in which it can be fitted into the cavity formed by the host molecules. 相似文献
5.
Queiroz MJ Abreu AS Ferreira PM Oliveira MM Dubest R Aubard J Samat A 《Organic letters》2005,7(22):4811-4814
[structure: see text] A new photochromic thieno-2H-chromene alpha-amino acid derivative was prepared by C-N palladium-catalyzed cross-coupling of a bromothieno-2H-chromene with the aminated aromatic side chain of the methyl ester of a N,N-diprotected amino acid. Its good photochromic properties demonstrated by flash photolysis and continuous irradiation indicate a possible application in ophthalmic lenses. It may also be inserted into peptides to give photoinduced reversible structural changes. 相似文献
6.
M. Gdaniec B. T. Ibragimov S. A. Talipov 《Journal of inclusion phenomena and macrocyclic chemistry》1990,9(3):231-242
The crystal structures of the lattice inclusion complexes of gossypol with benzene and chloroform have been determined by X-ray structure analysis. The crystals of (C30H30O8)2 · C6H6 (GPBNZ) are triclinic, space groupPI,a = 11.241(3),b = 14.986(4),c = 17.380(4) Å, = 98.89(2), = 99.86(2), = 98.91(2)°,V = 2800(2) Å3,Z = 2,D
x = 1.32 g cm–3, (CuK
) = 7.35 cm–1. The structure has been refined to a finalR value of 0.050 for 6146 observed reflections. The crystals of C30H30O8·CHCl3 (GPCLF) are monoclinic, space groupC2/c,a = 28.464(4),b = 8.948(1),c = 26.480(4) Å, = 108.93(2)°,V = 6380(2) Å3,Z = 8,D
x = 1.33 g cm–3, (CuK) = 30.42 cm–1. The structure has been refined to a finalR value of 0.100 for 1980 observed reflections.GPCLF forms an intercalate-type structure and GPBNZ a clathrate-type structure. There are, however, some similarities in the packing mode of the host molecules in these two structures. On a basis of comparison of the crystal packing of GPCLF and GPBNZ one can postulate that in the desorption process of the intercalate-type GPCLF complex an intermediate clathrate structure of the GPBNZ-type should be formed. 相似文献
7.
S. A. Talipov B. T. Ibragimov K. M. Beketov Sh. Yu. Islambekov R. G. Mardanov A. I. Ismailov 《Chemistry of Natural Compounds》1995,31(6):685-689
The results are given of an x-ray structural investigation of hemigossypolone isolated from the stems of a wiltinfected cotton plant and of gossypolone obtained by oxidizing gossypol. 相似文献
8.
I. S. Faizrakhmanov L. F. Zainullina R. F. Talipov A. Kh. Sharipov 《Russian Journal of Applied Chemistry》2007,80(2):272-274
Catalytic oxidation of a mixture of low-molecular-weight sulfides with atmospheric oxygen was studied. The catalytic activity of poly(cobalt phthalocyanine) in this process is higher than that of monomeric cobalt phthalocyanine. 相似文献
9.
B. T. Ibragimov S. A. Talipov Yu. K. Kushmuradov T. F. Aripov 《Chemistry of Natural Compounds》1982,17(5):432-436
In an investigation of the three-dimensional structure of the alkaloid matrine by x-ray structural analysis, a new stereoisomer of it has been detected, which has been called cis-matrine. In cis-matrine rings C and D are cis-linked, while the configurations of the A, B, and C fragments in cis-matrine and in ordinary matrine are identical. The cis-matrine molecule is characterized by a greater degree of strain than the molecule by ordinary matrine.Institute of Bioorganic Chemistry of the Academy of Sciences of the Uzbek SSR, Tashkent, and V. I. Lenin Tashkent State University. Translated from Khimiya Prirodnykh Soedinenii, No. 5, pp. 597–602, September–October, 1981. 相似文献
10.
B. T. Ibragimov S. A. Talipov B. N. Dadabaev A. A. Abduvakhabov 《Chemistry of Natural Compounds》1992,28(3-4):288-292
In crystals obtained from solutions in DMSO, gossypol molecules are again present in the aldehyde tautomeric form. These crystals are H-clathrates with the channel type of structure which has much in common with the structure of the complexes of gossypol with methanol and with formic acid.Institute of Bioorganic Chemistry, Uzbekistan Academy of Sciences, Tashkent. Translated from Khimiya Prirodnykh Soedinenii, Nos. 3,4, pp. 330–334, May–August, 1992. 相似文献