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1.
One- and two-dimensional homo- and heteronuclear correlation proton, carbon, proton—proton, and proton—carbon NMR spectra of fifteen drimanic sesquiterpenoids: 11,12-dibromodrima-5,8-dien-7-one, drim-8-en-7-one, 11-hydroxydrim-8-en-7-one, 11,12-dihydroxydrim-8-en-7-one, 11-hydroxy-11,12-epoxydrim-8-en-7-one, 11-hydroxy-11,12-epoxydrim-8-en-7-one, 8,9-epoxydriman-7-one, 8,9-epoxydriman-7-ol, 11,12-diacetoxydrim-8-en-7-ol, drimane-7,8,11-triol, 7,8-isopropylidenedioxydriman-11-al, 9, 11-dihydroxydrim-7-en-6-one, drimane-7,8,9-triol, drimane-7,8,11-triol, and drim-8-ene-7,11,12-triol were studied. The proton and carbon chemical shifts were assigned.__________Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 12, pp. 2589–2594, December, 2004.  相似文献   

2.
Zusammenfassung Analog wie in vorherigen Mitteilungen1–4 wurden -Pyridyl-hydrazono-cyanacetylcarbamidsäureäthylester (1), 1-(-Pyridyl)-5-cyan-6-azauracil (2), 1-(-Pyridyl)-6-azauracil-5-carbonsäure (3), deren Thioamid (4), und Amidoxim (5), welches in 1-(-Pyridyl)-5-[5-methyl-1,2,4-oxdiazolyl(3)]-6-azauracil (6) überge-führt wurde, hergestellt.
-Pyridylhydrazono-cyanacetylcarbamic acid ethyl ester (1), l-(-pyridyl)-5-cyano-6-azauracil (2), 1-(-pyridyl)-6-azauracil-5-carboxylic acid (3), its thioamide (4) and amidoxime (5) were prepared as described in preceding communications. (5) was converted into l-(-pyridyl)-5-[5-methyl-1,2,4-oxdiazolyl(3)]-6-azauracil (6).
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3.
Two new glycosides have been isolated from the seeds ofCoronilla glauca L. and C. scorpioides Koch: 3-(0-D-glucopyranosyloxy)-14. 15-dihydroxy-19-oxo-5-card-20(22)-enolide (alloglaucoside) and 3-(-D-gluco-ucofuranosyloxy)-5,14,19-trihydroxy-5-card-20(22)-enolide (scorpiosidol), together with a glycoside previously unknown for theCoronilla genus — 3-(-D-glucopyranosylo)g)-14-hydroxy-5-card-20(22)-enolide (desglucouzarin) and known aglycons (corotoxigenin, alloglaucotoxigenin, coroglaucigenin) and glycosides (glucocorotoxigenin, coronillobioside, glucocoroglaucigenin, coronillobiosidol and scorpioside).Ukraine Pharmaceutical Academy, Kharkov–2. Translated from Khimiya Prirodnykh Soedinenii, No. 3, pp. 372–376, May–June, 1996. Original article submitted August 14, 1995.  相似文献   

4.
The apparent kinetic parameters of the thermal decomposition of the-cyclodextrin-water complex were estimated from thermogravimetric data. Various calculation methods were used and the results compared. All methods except the Kissinger method gave a reaction order near to zero and an activation energy in the range 60 to 65 kJ/mol. Some trials were made to extrapolate the activation energy values to semi-isothermal conditions (65.7 kJ/mol). The loss in weight indicated the presence of 11 water molecules in the complex. This was liberated in single stage, despite its occurrence as two distinct types, as shown by crystallographic studies.
Zusammenfassung Auf Grundlage von thermogravimetrischen Daten wurden die scheinbaren kinetischen Parameter des Thermozerfalles von-Cyclodextrin-Wasser- Komplexen geschätzt. Die durch verschiedene Rechenmethoden erhaltenen Ergebnisse wurden in Tabelle 3 verglichen. Mit Ausnahme der Kissinger-Methode ergaben alle Verfahren eine Reaktionsordnung von annähernd Null und eine Aktivierungsenergie im Bereich 60–65 kJ/mol. Ausserdem wurde versucht, die Aktivierungsenergiewerte auf halbisotherme Bedingungen zu extrapolieren (65.7 kJ/mol). Der Masseverlust weist elf Wassermoleküle im Komplex nach, die in einem einzigen Schritt abgegeben werden, ungeachtet dessen, dass kristallographische Untersuchungen die Wassermoleküle zwei verschiedenen Typen zuordnen.

-- . , . , , — 60–65 · –1. (65,7 · –1). , , , , .
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5.
Solasodine (I) has been subjected to a number of transformations. The following compounds have been obtained from it by described procedures: 3-acetoxypregna-5,16-dien-20-one (II), 3-acetoxypregn-5-en-20-ol (III), and 3-acetoxypregn-5-en-20-ol (IV). The oxidation of (III) and (IV), the formation of an oxime, and the reduction of the oxime with sodium in ethanol, followed by Hess methylation, has led to 20-dimethylaminopregn-5-en-3-ol (IX) and to 20-dimethylaminopregn-5-en-3-ol (X). From compounds (IX) and (X), by analogy with (III) and (IV) by their oxidation and the preparation of oximes, which were then reduced and methylated, the following were obtained: 3,20-bisdimethylaminopregnane (XVII) and 3,20-bisdimethylaminopregnane (XVIII), and also quaternary salts of the latter.Institute of the Chemistry of Plant Substances, Academy of Sciences of the Uzbek SSR, Tashkent. Translated from Khimiya Prirodnykh Soedinenii, No. 3, pp. 370–374, May–June, 1980.  相似文献   

6.
New triterpene glycosides — salsolosides C and D — have been isolated from the epigeal part ofSalsola micranthera Botsch. On the basis of chemical transformations and physicochemical measurements, salsoloside C has been assigned the structure of oleanolic acid 28-0--D-glucopyranoside 3-0-[0--D-xylopyranosyl-(1 4)--D-glucuropyranoside], and salsoloside D has the structure of hederagenin 28-0--D-glucopyranoside 3-0-[0--D-xylopyranosyl-(1 4)--D-glucuropyranoside].Institute of the Chemistry of Plant Substances, Academy of Sciences of the Uzbek SSR, Tashkent. Translated from Khimiya Prirodnykh Soedinenii, No. 6, pp. 727–732, November–December, 1983.  相似文献   

7.
Hydroperoxide-dependent naphthalene hydroxylation involving rat liver microsomes has been studied. The direct interaction between cytochrome p-450 and cumyl hydroperoxide (CHP) has been demonstrated. Km values with respect to both the substrate and CHP have been determined using intact and induced enzyme systems. The nature of the hydroxylating agent and the possible role of high-valence iron in the processes of hydroxylation by microsomal systems is discussed.
. P-450 . Km . , .
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8.
In order to further explore the inclusion complexation behavior with -cyclodextrin dimers, the binding constants (KS) of three organoselenium bridged bis(-cyclodextrin)s (2ndash;4) tethered with a short linker were determined with some representative dye molecules in aqueous phosphate buffer solution (pH 7.20) at 25 °C by fluorescence and UV-vis spectrometry. As compared with the parent -cyclodextrin (1), the bridged bis(-cyclodextrin)s (2ndash;4) can not only significantly enhance the original binding affinity of the parent -cyclodextrin by the cooperative binding of one guest molecule in the closely located two -cyclodextrin cavities but also remarkably extend its molecular recognition abilities towards the different size/shape or substituent of model substrates. The higher binding ability and selectivity of dye molecules by bridged bis(-cyclodextrin)s (2ndash;4) are discussed from the viewpointof the size/shape-fit concept and multiple recognition mechanism.  相似文献   

9.
Two new steroid glycosides have been isolated from the leaves of aloe yucca and their structures have been established. Glycosides B and C are tigogenin penta-and hexaosides. Glycoside B, which we have called yuccaloeside B is (25R)-5-spirostan-3-ol 3-{[O--D-glucopyranosyl-(12)]-[O--L-rhamnopyranosyl-(14)-O--D-glucopyranosyl-(13)]-O--D-glucopyranosyl-(14)--D-galactopyranoside}, and glycoside C, which we have called yuccaloeside C is (25R)-5-spirostan-3-ol 3-{[(O--D-glucopyranosyl-(13)-O--D-glucopyranosyl-(12)]-[O--L-rhamnopyranosyl-(14)-O--D-glucopyranosyl-(13)]-O--D-glucopyranosyl-(14)--D-galactopyranoside}.N. G. Kutateladze Institute of Pharmacochemistry of the Georgian SSR Academy of Sciences, Tbilisi. Translated from Khimiya Prirodnykh Soedinenii, No. 4, pp. 537–542, July–August, 1987.  相似文献   

10.
The precipitates containing mainly iron, aluminium and magnesium hydroxides, obtained from phlogopite dissolved in nitric acid by means of the neutralization procedure with ammonia, have been investigated by thermal analysis (TG, DTG and DTA). According to the present study, which is part of a larger investigation into the chemical utilization of Finnish mica minerals, the formation of solid solutions between iron and aluminium hydroxides in silt increases with an increasing neutralization temperature. Nitrogen exists mainly in the form of nitrate in silts, and magnesium forms mixed hydroxides with aluminium, which causes a separation between the iron hydroxide and magnesium aluminium hydroxide phases.
Zusammenfassung Die von in Salpetersäure gelöstem Phlogopit durch Neutralisierung mit Ammoniak erhaltenen, hauptsächlich Eisen-, Aluminium- und Magnesiumhydroxid enthaltenden Niederschläge wurden thermoanalytisch (TG, DTG und DTA) untersucht. In der vorliegenden Arbeit, die Teil einer grossangelegten Untersuchung zur chemischen Nutzung finnischer Glimmermineralien ist, wird gezeigt, dass die Bildung fester Lösungen von Eisen- und Aluminiumhydroxiden in Schluff mit zunehmender Neutralisationstemperatur ansteigt. Stickstoff kommt in Schluff hauptsächlich in Form von Nitraten vor, und Magnesium bildet Mischhydroxide mit Aluminium, was eine Trennung der Eisenhydroxidphase von der Magnesium-Aluminium-Hydroxidphase bewirkt.

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