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101.
X-ray structural analysis has revealed that reaction of (BEDT-TTF)[HgCl3] with PhCl leads to the formation of a cation-radical salt (BEDT-TTF)4[Hg2Cl6]· PhCl, which exhibits a laminar crystal structure. The cationic layer is characterized by a grid or lattice network of contracted S...S intermolecular distances (3.396(4)–3.647(5) Å), which unite the BEDT-TTF cations in ribbons or bands, parallel to the [014] direction, and which also bind the ribbons together in a direction close to the [010] axis. The presence of this type of lattice network explains the metallic nature of the conductivity of this salt (BEDT-TTF)4Hg2Cl6]·PhCl in the temperature range 300.0–1.5 K, and is the basis of assigning this salt to a new class of organic, two-dimensional conductors. The [Hg2Cl6]2– anions and PhCl solvent molecules are united via secondary Hg...Cl 3.176(5) Å and Cl...Cl 3.480(6) Å interaction forces to form centrosymmetric tetramers [Hg2Cl6PhCl]2 4–, stretched out along the [014] axis direction.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 9, pp. 2062–2070, September, 1991.The authors wish to acknowledge R. N. Lyubovskaya for supplying the crystals and for helpful discussion of the results.  相似文献   
102.
Institute of the Chemistry of Plant Substances, Academy of Sciences of the Republic of Uzbekistan. Tashkent Pharmaceutical Institute. Translated from Khimiya Prirodnykh Soedinenii, No. 4, pp. 621–622, July–August, 1993.  相似文献   
103.
The preparation and spectral properties of rhamnose orthoacetates of aconitine and imperialine are described.Tashkent Pharmaceutical Institute. Institute of the Chemistry of Plant Substances, Academy of Sciences of the Republic of Uzbekistan, Tashkent. Translated from Khimiya Prirodnykh Soedinenii, No. 5, pp. 743–746, September–October, 1993.  相似文献   
104.
105.
This review gives information on the distribution of flavonoids (flavonol and anthocyanin glycosides, catechins, and proanthocyanidins in plants of the family Malvaceae, namely the various species of the genera Gossypium, Hibiscus, Altheae, etc. It is shown that the flavonols are represented by glycosides of kaempferol, quercetin, myricetin, herbacetin. gossypetin, and hibiscetin, the most widespread being glycosides of quercetin and kaempferol. Characteristic for the majority of representatives of the families that were studied are flavonols having a hydroxy group in the C-8 position. Anthocyanins are represented by glycosides of cyanidin and of delphinidin. However, together with these, glycosides of methoxylated anthocyanins have also been detected — peonidin, petinidin, and malvidin. Sources of a food dye have been revealed among representatives of the family. Literature sources up to 1991 have been included.A. S. Sadykov Institute of Bioorganic Chemistry, Academy of Sciences of the Republic of Uzbekistan, Tashkent, fax 627071. Translated from Khimiya Prirodnykh Soedinenii, No. 1, pp. 3–19, January–February, 1994.  相似文献   
106.
Equimolar mixtures of aromatic aldehydes with thioglycolic acid and thiosemicarbazide in H2SO4 transform into 2-amino-5-aryl-5H-thiazolo[4,3-b]-1,3,4-thiadiazoles.Translated fromIzvestiya Akademioi Nauk. Seriya Khimicheskaya, No. 3, pp. 763–764, March, 1996.  相似文献   
107.
108.
The Raman spectra of ClOF2 + cation in solutions of anhydrous HF were studied. In the ClOF2 +HF2 and ClOF2 +BF4 −HF systems, this cation exists as a pyramidal structure (C s symmetry), while in the ClOF2 +AuF6 −HF system, it exists as a planar structure (C 2v symmetry). Based on nonempirical calculations by the Hartree-Fock-Roothaan method, an explanation for the dependence of the structure of the ClOF2 + cation on the nature of the anion was proposed. For the Cl−O bond vibrations, the correlation functions of vibrational and rotational relaxations were calculated, and the characteristic times of these processes were determined. The main contribution to the formation of the band contours corresponding to the above-mentioned modes is made by the vibrational dephasing. Translated fromIzvestiya Akademii Nauk, Seriya Khimicheskaya, No. 3, pp. 432–437, March, 1998.  相似文献   
109.
The behavior of153Sm-EDTMP in vitro and vivo is analyzed by the size exclusion HPLC. The experimental results show that EDTMP amounts have an obvious effect on the stability in vitro and uptake of153Sm-EDTMP in the liver. HPLC analysis of urine sample indicates that153Sm-EDTMP es excreted in the original form. The behavior in vivo of153Sm-EDTMP containing 4 μg is similar to that of153Sm-EDTMP containing 50 μg EDTMP at 1 h post-injection.  相似文献   
110.
As shown by IR-spectroscopic studies, pyridine bases interacting with V2O5 and MoO3 supported on MgO form hydrogen bonds with surface hydroxyls and coordinate bonds with V and Mo ions. The interaction of 2,6-dimethylpyridine adsorbed on the surface with oxygen leads to the formation of 6-methylpyridine-2-carboxaldehyde, whose formyl group interacts with surface hydroxyls.
, V2O5 MoO3, MgO, V Mo. 2,6- 6--2-, OH-.
  相似文献   
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