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81.
B. G. Bazarov R. F. Klevtsova Ts. T. Bazarova L. A. Glinskaya K. N. Fedorov Zh. G. Bazarova O. D. Chimitova 《Russian Journal of Inorganic Chemistry》2006,51(5):794-799
Systems Tl2MoO4-E(MoO4)2 (E = Zr, Hf) are studied using X-ray powder diffraction, DTA, and IR spectroscopy. Compounds Tl8E(MoO4)6 and Tl2E(MoO4)2 are found in these systems. T-x diagrams for the Tl2MoO4-Zr(MoO4)2 system are designed. Single crystals are grown and structure is solved for Tl8Hf(MoO4)6. The compound crystallizes in a monoclinic structure with the unit cell parameters a = 9.9688(6) Å, b = 18.830(1) Å, c = 7.8488(5) Å, β = 108.538(1)°, Z = 2, space group C2/m. The main structural fragment is a [HfMo6O24]8? isle group. Three crystallographically independent types of Tl polyhedra uniformly fill spaces between [HfMo6O24]8? fragments to form a three-dimensional framework. 相似文献
82.
Zh. A. Krasnaya E. P. Prokof'ev M. Sh. Zaripova V. F. Kucherov 《Russian Chemical Bulletin》1973,22(10):2301-2303
Conclusions A number of dienic– keto esters was synthesized and it was shown that a labile equilibrium exists in them between the cis-dienones and -pyrans, and also between the cis- and trans-isomers at the , double bond.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 10, pp. 2356–2359, October, 1973. 相似文献
83.
G. E. Zhusupova N. A. Artamonova Zh. A. Abilov Zh. K. Orazbaeva 《Chemistry of Natural Compounds》2006,42(5):512-514
Pigments and lipids from the aerial parts of six plant species from the genus Limonium (Plumbaginaceae, Limoniacea) were studied. Xanthophylls dominated among the carotinoids; chlorophyll, the chlorophylls, according
to spectrophotometry. Unsaturated fatty acids, the content of which reached 80%, dominated in all samples according to GC.
The principal fatty acids were 18:1 and 18:2.
__________
Translated from Khimiya Prirodnykh Soedinenii, No. 5, pp. 412–414, September–October, 2006. 相似文献
84.
S. A. Zinova V. V. Isakov A. I. Kalinovskii Zh. I. Ul'kova K. P. Ulanova L. I. Glebko 《Chemistry of Natural Compounds》1992,28(3-4):305-311
The isolation of four triterpene glycosides from the roots of the dahurian anemonePulsatilla dahurica (Fisch. ex DC) Spreng, is described together with their identification, on the basis of chemical transformations, spectral characteristics, and literature analogies, as hederagenin 3-O--L-arabinoside, hederagenin 3-O-[O--D-glucopyranosyl-(12)--L-arabinopyranoside], hederagenin 3-O--L-arabinopyranoside 28-O-[O--L-rhamnopyranosyl-(14)--D-glucopyranosyl-(16)--D-glucopyranoside], and hederagenin 3-O-[O--D-glucopyranosyl-(14)--L-arabinopyranoside] 28-O-[O--L-rhamnopyranosyl-(14)--D-glucopyranosyl-(16)--D-glucopyranoside].Pacific Ocean Institute of Bioorganic Chemistry, Far Eastern Branch, Russian Academy of Sciences, Vladivostok. Translated from Khimiya Prirodnykh Soedinenii, Nos. 3,4, pp. 349–356, May–August, 1992. 相似文献
85.
M. Zh. Ovakimyan S. K. Barsegyan N. M. Kikoyan M. G. Indzhikyan 《Russian Journal of General Chemistry》2005,75(7):1069-1073
Triphenyl- and tributyl[2-(2-phenylhydrazino)ethyl]phosphonium salts undergo dehydrogenation on heating to form the corresponding phenylhydrazones in high yields. The phenylhydrazone formed from the triphenylphosphonium salt can also be prepared from triphenyl(1-alkoxy-2-bromoethyl)phosphonium bromides. The latter reaction is proposed to involve reduction of the COC group with phenylhydrazine. N,N-Diphosphonioethylation and N,N-diphosphoniopropylation of hydroxylamine are performed. Alkaline hydrolysis of the resulting diphosphonium salts gave N, N-bis[2-(diphenylphosphoryl)ethyl(propyl)]hydroxylamines in high yields.__________Translated from Zhurnal Obshchei Khimii, Vol. 75, No. 7, 2005, pp. 1132–1136.Original Russian Text Copyright © 2005 by Ovakimyan, Barsegyan, Kikoyan, Indzhikyan. 相似文献
86.
Sh. A. Alieva Zh. M. Putieva E. S. Kondratenko N. K. Abubakirov 《Chemistry of Natural Compounds》1978,13(5):546-549
Summary Six new diterpene glycosides — doronicosides A, B, C, D, E, and F — have been detected in the roots ofDoronicum macrophyllum Fisch. The qualitative and quantitative composition of the sugar chain of doronicoside D has been established. It has been shown that the negative aglycone of all the doronicosides is 15-hydroxy-(–)-kaur-16-en-19-oic acid, which, in the process of hydrolysis, is converted into 15-oxo-(–)-kauran-19-oic acid.Institute of the Chemistry of Plant Substances, Academy of Sciences of the Uzbek SSR, Tashkent. N. Narimanov Azerbaidzhan State Medical Institute, Baku. Translated from Khimiya Prirodnykh Soedinenii, No. 5, pp. 658–662, September–October, 1977. 相似文献
87.
O. V. Surov N. Zh. Mamardashvili G. P. Shaposhnikov O. I. Koifman 《Russian Journal of General Chemistry》2006,76(6):974-979
The temperature dependences of the vapor pressure of calix[4]arenes were determined by the Knudsen effusion method. Some calix[4]arenes can form congruently subliming intramolecular compounds with a solvent. The thermodynamic parameters of the sublimation of the compounds were calculated. Molecules of organic solvents incorporated in the cavity of calix[4]arenes stabilize the crystal lattice, increasing the enthalpy of sublimation. The electrostatic interactions presumably make a significant contribution to stabilization of the crystal lattice of stoichiometric complexes of calix[4]arenes with solvents. 相似文献
88.
N. Zh. Mamardashvili G. M. Mamardashvili 《Russian Journal of Inorganic Chemistry》2006,51(8):1270-1275
The formation of host-guest complexes between zinc diphenylporphyrinates of dimeric diphenylporphyrins and pyridine in toluene has been studied by the spectrophotometric titration method and 1H NMR spectroscopy. The zinc porphyrinates with pyridine form “internal” or “external” 1: 1 or 1: 2 complexes, depending on the length of binding ether O(CH2)nO bridges (n = 2, 3) of the cyclophane dimers and the reactant concentration. The stability constants of the porphyrinate-ligand complexes and concentration ranges of their formation have been determined. 相似文献
89.
Five-component reciprocal systems Na,K∥Cl,CO3,MoO4,WO4 and Na,K∥F,CO3,MO4,WO4 have been studied by differential thermal analysis (DTA) and X-ray powder diffraction (XPD). The systems have been triangulated to phase simplexes. The main reciprocal and complex-formation reactions have been revealed. The stability of [Na,K]2CO3, Na2[Mo,W]O4, and K2[Mo,W]O4 binary solid solutions and the nonexistence of quintuple invariant points in the title systems have been verified. 相似文献
90.
A. F. Prokof'eva Zh. Z. Sapozhnikova V. N. Volkova V. V. Negrebetskii L. A. Pokrovskaya N. N. Mel'nikov 《Chemistry of Heterocyclic Compounds》1991,27(7):772-778
A study was carried out of alkylation, acylation and aminomethylation reactions were studied in the 5-alkyl-4,5-dihydro-1,2,4-triazin-4-one series. Alkylation by alkyl halides proceeds in the presence of sodium methylate at the N
(1)
and N
(4)
atoms with the formation of a mixture of alkylated compounds of three types: derivatives of 4,5-dihydrotriazine, unsaturated triazine, and their dimers. Acylation with isocyanates leads to the formation of heterocyclic ureas — derivatives at the N
(4)
atom. Mono- and bisaminals were obtained by the reaction of triazines with ethoxymethyldiethylamine.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 7, pp. 963–970, July, 1991. 相似文献