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1.
Summary A polarographic method for the quantitative determination of narwedine inUngernia victoris and a chromatopolarographic method for its determination inU. severtzovii have been proposed.Institute of the Chemistry of Plant Substances, Academy of Sciences of the Uzbek SSR. Translated from Khimiya Prirodnykh Soedinenii, No. 5, pp. 610–612, September–October, 1975.  相似文献   

2.
The following substances have been isolated from an acetone extract ofFerula gigantea B. Fedtsch.: a coumarin — umbelliferone, C9H6O2, mp 230–233°C; and sesquiterpene lactones — talassin A, C25H30O7, mp 188–191°C; malaphyllinin, C24H24O7, mp 231–235°C; malaphyll, C29H32O9, mp 212–213°C; and malaphyllin, C26H28O9, mp 216–218°C. Structures have been proposed for three new sesquiterpene lactones on the basis of an analysis of their spectral characteristics.All-Union Scientific-Research Institute of Medicinal Plants, Moscow. M. V. Lomonosov Moscow State University, Botanical Garden, Moscow. Translated from Khimiya Prirodnykh Soedinenii, No. 4, pp. 490–495, July–August, 1979.  相似文献   

3.
The atomic inner-shell vacancy decay processes comprised of radiative and nonradiative transitions are characterized by the fluorescence, Auger and Coster-Kronig yields. We present a review of our recent measurements of the Li (i=1, 2, 3) sub-shell fluorescence yields (ωi) and the L1–L3 Coster-Kronig transition probabilities (f13) for elements with 70Z92 following photoionization. The comparison of the measured ωi and f13 values with the theoretical ones, based on the relativistic Dirac–Hartree–Slater (RDHS) model calculations, indicated the need for more refined calculations of transition probabilities for different Coster-Kronig transitions.  相似文献   

4.
Summary Fifteen bases have been isolated from three species ofCorydalis. Dihydrosanguinarine has been isolated from a plant of the genusCorydalis for the first time.Institute of the Chemistry of Plant Substances, Academy of Sciences of the Uzbek SSR. Translated from Khimiya Prirodnykh Soedinenii, No. 5, pp. 612–615, September–October, 1975.  相似文献   

5.
In addition to the alkaloids known previously from this plant, haplofoline and folifine, from the epigeal part ofHaplophyllum foliosum we have isolated norgraveoline with mp 288–289°C (decomp. from acetone), and myrtopsine with mp 201–202°C (from chloroform), []D-5° (c 0.05; methanol), which were first obtained fromHaplophyllum dubium andMyrtopsis sellingii, respectively. We have confirmed by the PMR-spectroscopic method the positions of the substituents in the dihydrofuran ring of myrtopsine suggested previously on the basis of biogenetic considerations. In addition, it has been established that the substituents are present in the trans form. This is the first time that myrtopsine has been detected in plants of the genusHaplophyllum.Institute of the Chemistry of Plant Substances of the Academy of Sciences of the Uzbek SSR, Tashkent. Translated from Khimiya Prirodnykh Soedinenii, No. 5, pp. 613–616, September–October, 1981.  相似文献   

6.
Water-soluble polysaccharides have been isolated from two species ofEremurus — E. lactiflorus andE. luteus — with yields of 13.5% and 20.5%, respectively. They contained mainly glucose and mannose in ratios of 1:5 and 1:3.1. The polysaccharides ofE. lactiflorus were separated from a column of DEAE-cellulose. The yield of neutral fraction was 10.3%. Gel filtration of the polysaccharides on Sephadex G-200 showed their polydispersity. Homogeneous fractions were obtained by fractional precipitation with ethanol. They have been characterized with respect to monosaccharide composition, molecular weight, and IR spectra.Institute of the Chemistry of Plant Substances, Academy of Sciences of the Uzbek SSR, Tashkent. Translated from Khimiya Prirodnykh Soedinenii, No. 5, pp. 604–608, September–October, 1979.  相似文献   

7.
The optimum conditions for extracting flavonols fromAlhagi pseudoalhagi has been determined. A method for the UV-spectrometric identification of the total alkaloids has been developed which permits reliable reproducible results to be obtained. The relative error of the determination does not exceed ±1.7%.Tashkent State University. Translated from Khimiya Prirodnykh Soedinenii, No. 5, pp. 664–667, September–October, 1993.  相似文献   

8.
The equilibrium structures, binding energies, and vibrational spectra of the clusters CH3F(HF)1 n 3 and CH2F2(HF)1 n 3 have been investigated with the aid of large-scale ab initio calculations performed at the Møller–Plesset second-order level. In all complexes, a strong C–FH–F halogen–hydrogen bond is formed. For the cases n = 2 and n = 3, blue-shifting C–HF–H hydrogen bonds are formed additionally. Blue shifts are, however, encountered for all C–H stretching vibrations of the fluoromethanes in all complexes, whether they take part in a hydrogen bond or not, in particular also for n = 1. For the case n = 3, blue shifts of the ν(C–H) stretching vibrational modes larger than 50 cm−1 are predicted. As with the previously treated case of CHF3(HF)1 n 3 complexes (A. Karpfen, E. S. Kryachko, J. Phys. Chem. A 107 (2003) 9724), the typical blue-shifting properties are to a large degree determined by the presence of a strong C–FH–F halogen–hydrogen bond. Therefore, the term blue-shifted appears more appropriate for this class of complexes. Stretching the C–F bond of a fluoromethane by forming a halogen–hydrogen bond causes a shortening of all C–H bonds. The shortening of the C–H bonds is proportional to the stretching of the C–F bond.  相似文献   

9.
FromFumaria vaillantii, collected in the Tashkent province, 18 alkaloids have been isolated of which N-methyladlumine with mp 198–199°C, []D-45° (c 0.5; methanol) has proved to be new. Its structure has been established on the basis of spectral characteristics and a direct comparison withl-adlumine methiodide.Institute of the Chemistry of Plant Substances of the Academy of Sciences of the Uzbek SSR, Tashkent. Translated from Khimiya Prirodnykh Soedinenii, No. 5, pp. 602–604, September–October, 1981.  相似文献   

10.
Summary A chromatographic method has been developed for the quantitative determination of the alkaloids ofAnabasis aphylla — anabasine, aphylline, lupinine, aphyllidine, and anabasamine — and also pachycarpine in the mixture of reduction products of the high-boiling fraction of alkaloids, in a thin layer of alumina.V. I. Lenin Tashkent State University. Translated from Khimiya Prirodnykh Soedinenii, No. 6, pp. 772–776, November–December, 1976.  相似文献   

11.
A method has been developed for isolating ecdysterone from the inflorescences ofRh. integrifolium. The yield is 0.15% on the weight of the raw material.Institute of the Chemistry of Plant Substances, Academy of Sciences of the Uzbek SSR, Tashkent. Translated from Khimiya Prirodnykh Soedinenii, No. 5, pp. 667–668, September–October, 1979.  相似文献   

12.
A spectrophotometric method has been developed for the quantitative separate determination of the total flavonones and isoflavones when they are present together in an extract ofThermopsis alterniflora.Institute of the Chemistry of Plant Substances, Academy of Sciences of the Republic of Uzbekistan, Tashkent. Translated from Khimiya Prirodnykh Soedinenii, No. 5, pp. 667–669, September–October, 1993.  相似文献   

13.
A method is described for the isolation and purification of lipoprotein lipase activity from the culture liquid of the fungusRhizopus microsporus. Some properties of the homogeneous enzyme have been studied: molecular weight 43,000, pI 3.7.Institute of Microbiology, Academy of Sciences of the Uzbek SSR, Tashkent. Translated from Khimiya Prirodnykh Soedinenii, No. 3, pp. 373–376, May–June, 1981.  相似文献   

14.
Two aromatic polyaminocarboxylate ligands, ethylenediaminedi(o-hydroxyphenylacetic acid) (EDDHA) and N,N′-bis(hydroxybenzyl)ethylenediamine-N,N′-diacetic acid (HBED), were applied for the separation of transition and heavy metal ions by the ion-exchange variant of electrokinetic chromatography. EDDHA structure contains two chiral carbon centers. It makes it impossible to use the commercially available ligand. All the studied metal ions showed two peaks, which correspond to meso and rac forms of the ligand. The separation of metal–HBED chelates was performed using poly(diallyldimethylammonium) polycations in mixed acetate–hydroxide form. Simultaneous separation of nine single- and nine double-charged HBED chelates, including In(III), Ga(III), Co(II)–(III) and Mn(II)–(III) pairs demonstrated the efficiency of 40 000–400 000 theoretical plates. The separation of Co(III), Fe(III) complexes with different arrangements of donor groups and oxidation of Co(II), Mn(II), Fe(II) ions in reaction with HBED have been discussed.  相似文献   

15.
A sesquiterpene lactone with mp 97–99°C, C15H20O3, identified as deoxy--santonin, has been isolated from the epigeal part ofArtemisia hanseniana var.phylostachus.V. L. Komarov Institute of Botany of the Academy of Sciences of the Azerbaidzhanian SSR, Baku. Translated from Khimiya Prirodnykh Soedinenii, No. 5, pp. 564–568, September–October, 1981.  相似文献   

16.
Summary From the epigeal part ofStizolophus balsamita (Lam.) Cass. ex Takht. a new sesquiterpene lactone balsamin has been isolated with the composition C20H26O6, mp 242–244°C (from ethanol), [] D 17 –45.70° (c 1.9; chloroform). Do the basis of the basis of the IR, UV, and PMR spectra of balsamin and its acetate, a stereochemical structure has been proposed for balsamin, and the structures of stizolin and stizolicin isolated previously from the same plant have also been supplemented by stereochemistry.All-Union Scientific-Research Institute of Medicinal Plants, Moscow. Translated from Khimiya Prirodnykh Soedinenii, No. 4, pp. 467–472, July–August, 1976.  相似文献   

17.
From the total extractive substances of the roots ofFerula stylosa two esters have been isolated: chimganin and a new one — stylosin. The structure of stylosin is suggested as the ester of 4-hydroxy-3-methoxybenzoic acid and the monoterpene alcohol fenchol.Azerbaidzhan SSR, Baku, and All-Union Scientific-Research Institute of Medicinal Plants, Moscow. Translated from Khimiya Prirodnykh Soedinenii, No. 6, pp. 789–791, November–December, 1980.  相似文献   

18.
Ten oligosaccharides have been isolated from the products of the partial hydrolysis of a native acetylated glucomannan obtained fromEremurus lactiflorus O. Fedtsch. Their structures have been studied with the aid of acid hydrolysis before and after reduction with NaBH4, by the GLC method, and also by chromatography with markers. The compositions and sequence of the monomers in tetra- and heptaoligo-saccharides have been determined by the13C NMR method. The glucommannan ofE. lactiflorus differs from theEremurus glucomannans studied previously by the ratio of monosaccharides, the presence of 0-Ac groups, the degree of polymerization, and the presence of a cellobiose unit (Glcp-Glcp) in the polymer chain. The repeating unit consists of 14 hexose residues.Institute of the Chemistry of Plant Substances, Academy of Sciences of the Uzbek SSR, Tashkent. Translated from Khimiya Prirodnykh Soedinenii, No. 6, pp. 680–684, November–December, 1982.  相似文献   

19.
A new ecdysteroid with the composition C27H44O6 which has been called brahuisterone has been isolated from the epigeal part of the plantSilene brahuica Boiss. Its chemical and complete spatial structures have been established by spectral studies and the x-ray structural method (diffractometer, Cu-K radiations, 996 reflections, direct method, R=0.119).Institute of the Chemistry of Plant Substances, Academy of Sciences of the Uzbekistan Republic, Tashkent. Translated from Khimiya Prirodnykh Soedinenii, No. 4, pp. 553–558, July–August, 1993.  相似文献   

20.
A novel method for the synthesis of N-alkyl-3-acyl-4-alkoxycarbonylmethylpyrrolidine-2,5-diones (3) was accomplished. α-Oxoketene O,N-acetals (1) reacted with maleic anhydride (2) at 80–110 °C for 5 h without solvent to give 3 in moderate to good yield (36–74%). Single X-ray crystallographic analysis showed that the two substituents on C-3 and C-4 were trans.  相似文献   

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