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1.
Summary From a methanolic extract of the roots ofPrangos ferulacea (L) Lindl., growing in the Nakhichevan ASSR, in addition to the compounds found previously, another six substances (I–VI) have been isolated, of which (I) and (VI) have been identified as, respectively, meransin hydrate monoacetate, found for the first time in nature, and umbelliferone: and in the study of a crystalline mixture obtained from the resin of the roots of the plant under investigation collected in Armenia, two coumarins — (VII) and (VIII) — have been isolated.On the basis of a study of IR, NMR, and mass spectra and chemical properties, the structures of the six new cumarin derivatives (II–V, VII, and VIII) have been established. Compound (II) has the structure of 8-(3-methylbutenyloxy)furo-2,3:7,6-coumarin and has been called feruliden; (III) is 7-hydroxy-8-(3-hydroxy-2-senecioyloxyisopentyl) coumarin and has been called ferudiol; (IV) is 7-hydroxy-8-(3-methoxy-2-senecioyloxyisopentyl) coumarin; (V) is 5-[1-(2,3-dihydroxy-3-methylbutyroyloxy)-1-methylethyl]-4,5-dihydrofuro-2,3:7,6-coumarin and has been called lindiol; (VII) is 8-(2-hydroxy-3-methylbut-3-enyloxy)-7-methoxycoumarin and has been called ferudenol; (VIII) is 7-methoxy-8-(3-methyl-2-oxobut-3-enyl)coumarin and has been called prangone.Leningrad Sanitary-Hygenic Medical Institute. Translated from Khimiya Prirodnykh Soedinenii, No. 5, pp. 568–574, September–October, 1974.  相似文献   

2.
Conclusions For the first time in the isoflavone series, a compound which has the structure of 5,7-dihydroxy-3,4-methylenedioxyisoflavone (3,4-methylenedioxyorobol) and two of its glucosides — 3,4-methylenedioxyorobol 7-O--D-glucoside and 3,4-methylenedioxyorobol 7-O--D-glucosylglucoside — and also a genistein C-monoglucoside, have been described. The isoflavones were isolated from the roots ofLupinus luteus L. by preparative chromatography on paper and on columns of polyamide. In addition, the previously known genistein, genistein 7-O--D-glucoside (genistin), and genistein 7-O--D-glucosylglucoside have been obtained.V. F. Kuprevich Institute of Experimental Botany, Academy of Sciences of the Belorussian SSR. Translated from Khimiya Prirodnykh Soedinenii, No. 2, pp. 162–166, March–April, 1974.  相似文献   

3.
Conclusion The reaction of 20,20-dimethoxy-16,17-epoxypregn-5-ene-3,21-diol-20-one with pyridine thiocyanate in the presence of carbethoxyhydrazine proceeds by two competing paths: cisopening of the oxide ring by a -SCN ion at the C17 atom, and substitution of one of the methoxyl groups by -NCS ion. As a result 2,20-dicarbethoxyhydrazones of pregn-5-ene-3,21-diol-20-one-[17,16-d]-1,3-oxathiolan-2-one and 20-methoxy-16,17-epoxypregn-5-ene-3-ol-[20,21-d]-1,3-oxazolidine-2-thione are formed.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 4, pp. 911–914, April, 1987.  相似文献   

4.
Hydrogen desorption proceeds in several temperature regions and differs by its order of magnitude and activation energy. Differential curves of adsorbed hydrogen distribution with respect to the desorption activation energy, dN/dE (E), show a considerable inhomogeneity of adsorbed atomic species and the energetic homogeneity of molecular species.
. dN/dE (E) .
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5.
A new numerical method for the determination of thermokinetics is proposed. This is based on the spectral resolution of a thermal curve into the basic set of unit rectangular pulse curves orthogonalized by Löwdin's transformation. A numerical example shows that the present method can be successfully applied to experimental curves.
Zusammenfassung Eine neue numerische Methode zur Bestimmung von Thermokinetika wird vorgeschlagen. Sie beruht auf der spektralen Auflösung einer thermischen Kurve in die Grundfolge von Einheiten rechteckiger Pulskurven, welche durch eine Löwdins Transformation orthogonalisiert worden sind. Ein numerisches Beispiel zeigt, dass diese Methode bei experimentellen Kurven mit Erfolg eingesetzt werden kann.

ë- . , .
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6.
Propylene metathesis over catalysts prepared by coordination of Mo(V) oxalate to -Al2O3 has been studied.
, (V) -Al2O3.
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7.
A new low-cost, simple cell for transmission IR or UV/VIS measurements on solid catalysts is described. The cell may be easily adapted to various applications by simple replacing of some its elements by others.
, . , .
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8.
As shown by temperature-programmed desorption (TPD), the quantity of reversibly chemisorbed propane on MoO3 passes through a maximum depending on the degree of surface reduction. Using the ESR method, it is shown that the centers of propene chemisorption do not contain Mo5+ ions but presumably isolated Mo4+ ions.
, MoO3 . , Mo+5. , Mo+4.
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9.
Summary 1. The synthesis of the following neutral plasmalogens has been effected: -O-(octadec-1-enyl)-, distearoylglycerol, -O-(octadec-1-enyl)-, -dipalmitoylglycerol, -O-(hexadec-1-enyl)-, -distearoylglycerol, and -O-(pentadec-1-enyl)-, -dipalmitoylglycerol.2. During the synthesis, the following compounds were isolated and characterized by their physicochemical constants: the -octadec-1-enyl ether of glycerol, -(2-hydroxyoctadecyl) , -isopropylideneglyceryl ether, the tosylate of -(2-hydroxyoctadecyl) , -isopropylideneglyceryl ether, and -O-(2-tosyloxyoctadecyl) glycerol.3. The IR spectra of the -octadec-1-enyl ether of glycerol and the neutral plasmalogens have been studied.Khimiya Prirodnykh Soedinenii, Vol. 2, No. 6, pp. 367–371, 1966  相似文献   

10.
It has been established that at low temperatures of TiCl4+AOC catalyst preparation in solution (with Ti/Al1/15), ESR spectra exhibit rhombic anisotropy of the g-factor. Experiments with the sample having 61 % concentration of47Ti isotopes suggest the formation of associates of Ti3+ with magnetic ordering, apparently due to the Jahn-Teller cooperative effect.
TiCl4+ AOC ( Ti/Al1/15) g-. 47Ti (61%) Ti3+ , , -.
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