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1.
Conclusions The triterpene glycosides scabiosides D, E, F, and G have been isolated from the roots ofPatrinia scabiosofolia Fisch. et Link. It has been established that scabioside D is O--D-glucopyranosyl-(1 4)-O--L-arabopyranosyl-(1 3)-O-oleanoloyl-(28 1)--D-xylopyranose, and scabioside E is O--D-glucopyranosyl-(1 4)-O--L-arabopyranosyl-(1 3)-O-oleanoloyl-(28 1)-O--D-xylopyranosyl-(4 1)--L-rhamnopyranose.  相似文献   

2.
Two new steroid glycosides have been isolated from the generative organs (pericarps and peduncles) ofAllium cepa L.: alliospiroside A and alliofuroside A. According to chemical transformations and spectral characteristics, alliospiroside A has the structure of (25S)-spirost-5-ene-1,3-diol 1-O-[O--L-rhamnopyranosyl-(1 2)--L-arabinopyranoside]. The structure of (25S)-furost-5-ene-1,3,22,26-tetraol 20-O--D-glucopyranoside 1-O-[O--L-rhamnopyranosyl-(1 2)--L-arabinopyranoside] has been established for alliofuroside A.Institute of the Chemistry of Plant Substances of the Academy of Sciences of the Uzbek SSR, Tashkent. Translated from Khimiya Prirodnykh Soedinenii, No. 2, pp. 188–196, March–April, 1986.  相似文献   

3.
Two new terpene glycosides have been isolated from the leaves of the foxgloveDigitalis ciliata Trautv.: -D-glucopyranosyl oleanolate 3-O-[O--D-xylopyranosyl-(1 4)--L-rhamnopyranoside] and oleanolic acid 3-O-[O--D-xylopyranosyl-(1 4)--L-rhamnopyranoside].I. G. Kutateladze Institute of Pharmacochemistry Academy of Sciences of the Georgian SSR, Tbilisi. Translated from Khimiya Prirodnykh Soedinenii, No. 2, pp. 246–251, March–April, 1991.  相似文献   

4.
Conclusions From the fraction of the feebly polar saponins ofPatrinia scabiosofolia Fisch. et Link oleanolic acid, hederagenin, -sitosterol, -D-glucopyranoside, and hederagenin 3--L-arabopyranoside have been isolated.The polar fraction has yielded two triterpene glycosides. It has been established that one of them is oleanolic acid 3-O--D-glucopyranosyl-(1 4)--L-arabinopyranoside, and the other is hederagenin 3-O--D-glucopyranosyl-(1 4)--L-arabopyranoside.Khimiya Prirodnykh Soedinenii, Vol. 6, No. 1, pp. 69–74, 1970  相似文献   

5.
    
Two new triterpene glycosides — cucmariosides C1 and C2 — have been isolated from the Far Eastern holothurianEupentacta (=Cucumaria)fraudatrix Djakonov et Baranova. Their structures have been established with the aid of13C NMR and PMR spectroscopy, partial acid hydrolysis, periodate oxidation, and methylation as 16-acetoxy-3-{[3-O-methyl--D-xylopyranosyl-(13)--D-glucopyranosyl-(14)] [-D-xylopyranosyl-(12)]--D-quinovopyranosyl-(12)--D-xylopyranosyloxy}holosta-7,23,24(cis)-triene and 16-acetoxy-3-{[3-O-methyl--D-xylopyranosyl-(13)--D-glucopyranosyl-(14)] [-D-xylopyranosyl-(12)]--D-quinovopyranosyl-(12)--D-xylopyranosyloxy}holosta-7,22,24(trans)-triene, respectively.Pacific Ocean Institute of Bioorganic Chemistry of the Far-Eastern Scientific Center of the USSR Academy of Sciences, Vladivostok. Translated from Khimiya Prirodnykh Soedinenii, No. 6, pp. 831–837, November–December, 1987.  相似文献   

6.
Conclusions Two additional cardiac glycosides, glucoerysimoside and glucoerysimosol, have been isolated from the seeds ofCheiranthus allioni Hort. Glucoerysimoside is strophanthidin 3-[O--D-digitoxopyranosyl-(4 1)-O--D-glucopyranosyl-(4 1)--D-glucopyranoside]. Glucoerysimosol is a new cardenolide having the same carbohydrate component, but its aglycone is strophanthidol. From these glycosides a new trisaccharide has been obtained which has been characterized as 4-O--cellobiosyl-D-digitoxose.Khar'kov Scientific-Research Institute of Pharmaceutical Chemistry. Translated from Khimiya Prirodnykh Soedinenii, No. 5, pp. 566–571, September–October, 1970.  相似文献   

7.
Conclusions The structure of two triterpone glycosides fromSapindus mukorossi Gaertn. has been established. It has been shown that sapindoside A is hederagenin 3-O--L-arabinosyl-(2 1)--L-rhamnopyranoside and sapindoside B is the 3-O--L-arabopyranosyl-(2 1)-O--L-rhamnopyranosyl-(3 1)--D-xylopyranoside.  相似文献   

8.
In order to elucidate the role of water in the basic condensation of triphenylsilane in moist ethanol, the kinetic law, the activation energy and entropy were determined. A two-step mechanism discarding ethanol as reactant is proposed.
- , , . , .
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9.
Summary The virtual charge model (Tapia model) in conjunction with the CNDO/S-CI approximation in the frame of SCF-MO theory was employed to study the effects of solvent on the electronic structures and spectra of benzaldehyde and acetophenone molecules. The CNDO/S calculations in presence of solvation indicate a satisfactory interpretation of the medium effects on the electronic structures and spectra of the molecules investigated. The prediction of our MO calculations by means of the Tapia model concerning the solvochromic shifts of n * and * transitions are in accord with the observed trends which indicate a blue shift for the n * band and a red shift for the * band upon a change of solvent from non-polar to polar solvents.
Anwendung des Virtual Charge-Modells auf die Elektronenstrukturen und Spektren von Benzaldehyd und Acetophenon
Zusammenfassung Das Virtual-Charge-Modell (Tapia-Modell) im Zusammenhang mit der CNDO/S-CI-Näherung im Rahmen der SCF-MO-Theorie wurde zum Studium der Lösungsmitteleffekte auf die Elektronenstrukturen und Spektren von Benzaldehyd und Acetophenon herangezogen. Die CNDO/S-Rechnungen bei Anwesenheit von Solvens erlauben eine befriedigende Interpretation der Mediumeffekte auf Elektronenstrukturen und Spektren der untersuchten Verbindungen. Die aus MO-Rechnungen folgenden Voraussagen ergeben auf Basis des Tapia-Modells solvatochrome Verschiebungen für die n *- und *-Übergänge. Die vorausgesagten Effekte stehen im Einklang mit den experimentell beobachteten Trends: Blauverschiebung für die n *-Bande und Rotverschiebung für die *-Bande beim Wechsel von nichtpolarem zu polarem Lösungsmittel.
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10.
The kinetics of curing of triglycidyl-p-aminophenol with four different diamines in stoichiometric amounts were investigated by means of differential scanning calorimetry. The results indicated that the curing reaction follows first-order Arrhenius kinetics with an activation energy in the range 40–70 kJ · mol–1. The effect of the structure of the curing agent on the curing characteristics is discussed on the basis of the curing characteristics and the kinetic parameters. An epoxy fortifier was observed to lower the curing temperature of an epoxy-amine system when incorporated prior to curing.
Zusammenfassung Mittels Differential-Scanning-Kalorimetrie wurde die Kinetik der Vernetzung von Triglycidyl-p-aminophenol mit stöchiometrischen Mengen vier verschiedener Amine untersucht. Laut den Ergebnissen verläuft die Vernetzungsreaktion mit einer Arrhenius-Kinetik erster Ordnung, wobei die Aktivierungsenergie im Bereich von 40–70 kJ/mol liegt. Auf Grundlage der Vernetzungscharakteristika und der kinetischen Parameter wird der Einfluss der Struktur des Vernetzungsreagenz auf die Vernetzungskenndaten beschrieben. Mit einem vor der Vernetzung eingebrachten Epoxyfortifyers konnte die Vernetzungstemperatur eines Epoxy-Amin-Systemes heruntergesetzt werden.

-- , . , 40–70 ·–1. . , , , .


One of the authors (R.D.P.) is grateful to the University Grants Commission, New Delhi, for the award of a Research Associateship under the Special Assistance Programme.  相似文献   

11.
Echinocystic acid 3-sulfate and new 3-sulfates — of the 28-O-[O--L-rhamnopyranosyl-(14)-O--D-glucopyranosyl-(16)--D-glucopyranosyl esters of oleanolic and echinocystic acids have been isolated from the leaves of Crimean ivyHedera taurica Carr. (fam. Araliaceae).M. P. Frunze Simferopol' State University. Translated from Khimiya Prirodnykh Soedinenii, No. 6, pp. 683–686, November–December, 1992.  相似文献   

12.
The structure of an extracellular mannan formed by the yeastBullera tsugae has been studied. It has been shown that the repeating unit of this polysaccharide contains -(13)- and -(14)-bound D-mannopyranose residues in equimolar ratio. A comparison has been made of the polymer under investigation with the extracellular mannan from a yeast of the genusRhodotorula. Leningrad Institute of Pharmaceutical Chemistry. Translated from Khimiya Prirodnykh Soedinenii, No. 6, pp. 746–750, November–December, 1985.  相似文献   

13.
Summary FromAllium narcissiflorum Wells have been isolated for the first time trillin and a glycoside B, which proved to be 3-O-[-O-D-glucopyranosyl-(1 3)-O--D-glucopyranosyl-(1 6)-O--D-glucopyranosyl-(1 ]-26-O-[-D-glucopyranosyl-(1 ]-25R-furost-5-ene-3,22 , 26-triol.Institute of Chemistry, Academy of Sciences of the Moldavian SSR, Kishinev. Translated from Khimiya Prirodnykh Soedinenii, No. 1, pp. 55–58, January–February, 1976.  相似文献   

14.
Summary 7-(3,3-Dimethylallyloxy)-6-methoxycoumarin and two new coumarins — ramosin and ramosinin — have been isolated from the epigeal part ofHaplophyllum ramosissimum.On the basis of IR, PMR, and mass spectroscopy and chemical reactions, the structure of 8-(3,3-dimethylallyl)-7-(3,3-dimethylallyloxy)coumarin (II) has been proposed for ramosin and that of 3-(1,1-dimethylallyl)-8-(3,3-dimethylallyl)-7-methoxycoumarin (III) for ramosinin.Leningrad Sanitary-Hygienic Medical Institute. Institute of Chemistry, Academy of Sciences of the Turkmen SSR, Ashkhabad. Translated from Khimiya Prirodnykh Soedinenii, No. 1, pp. 15–17, January–February, 1979.  相似文献   

15.
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   

16.
We have isolated from Crimean ivy berries in addition previously known triterpene glycosides — 3-O--L-arabinopyranosyl-28-O-[O--L-rhamnopyranosyl-(1 4)-O--D-glycopyranosyl-(1 6)--D-glucopyranosyl]hederagenin, 3-O-[O--L-rhamnopyranosyl-(1 2)--L-arabinopyranosyl]-28-O-[O--L-rhamnopyranosyl-(1 4)-O--D-glucopyranosyl-(1 6)--D-glycopyranosyl]hederagenin, the new triterpene glycosides hederoside H2-3-O-[O--D-glycopyranosyl-(1 2)--D-glycopyranosyl-(1 2)--D-glucopyranosyl]-28-O-[O--D-glucopyranosyl-(1 6)--D-glucopyranosyl]oleanolic acid- and hederoside I-3-O-[O--D-glucopyranosyl-(1 2)--D-glucopyranosyl]-28-O-[O--D-glucopyranosyl-(1 6)--D-glucopyranosyl]hederagenin. Details of their13C NMR spectra are given.M. V. Frunze Simferopol' State University. Translated from Khimiya Prirodnykh Soedinenii, No. 6, pp. 779–783, November–December, 1990.  相似文献   

17.
Two new glycosides have been isolated from the total triterpene glycosides of the holothurianDuasmodactyla kurilensis: kurilosides A (III) and C (IV). It has been established that (III) is 16-acetoxy-3-{[O--D-glucopyranosyl-(1 4)-O--D-quinovopyranosyl-(1 2)]-[O-(3-O-methyl--D-glucopyranosyl)-(1 3)-O-(6-O-(sodium sulfato)--D-glucopyranosyl)-(1 4)]--D-xylopyranosyloxy}-4,4,14-trimethylpregen-9(11)-en-20-one, while the minor glycoside (IV) is 16-acetoxy-3-{O--D-quinovopyranosyl-(1 2)-[O-(3-O-methyl--D-glucopyranosyl-(1 3)-O-(6-O-(sodium sulfato)--D-glucopyranosyl)-(1 4)]--D-xylopyranosyloxy}-4,4,14-trimethylpregn-9(11)-en-20-one.Pacific Ocean Institute of Bioorganic Chemistry, Far Eastern Branch, Academy of Sciences of the USSR, Vladivostok. Translated from Khimiya Prirodnykh Soedinenii, No. 2, pp. 221–226, March–April, 1991.  相似文献   

18.
Studies of the effect of zinc chloride and aluminium additives on the activity of a Pd/Al2O3 catalyst (5 wt.%Pd) in the isomerization of heptene-1, allylbenzene,p-allylphenol and 4-allyl-2-methoxyphenol (eugenol) indicate that the rate and selectivity of isomerization depend on the sequence of addition of salts and reagent to the catalytic system. The simultaneous addition of ZnCl2 or AlCl3 with olefin, produces a 2–3 fold increase in the isomer yield compared to ethanol.
Pd/Al2O3- (5 .% Pd) -1, , -, 4--2- (). , . ZnCl2 AlCl3 2–3 .
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19.
Zusammenfassung 4-Hydroxy-2-alkenale verschiedener Kettenlänge (C5–C10) werden in einer mehrstufigen Synthese hergestellt: Alkanal 2-Bromalkanaldimethylacetal 2-Alkenaldimethylacetal 4-Brom-2-alkenaldimethylacetal 4-Hydroxy-2-alkenaldimethylacetal 4-Hydroxy-2-alkenal.  相似文献   

20.
Six proanthocyanidins have been isolated from the roots ofPolygonium coriarium. The structures of three oligomeric proanthocyanidins have been established: taranin, consisting of [epigallocatechin gallate]-(48)-[epigallocatechin gallate]-(48)-[epigallocatechin-(48)-epigallocatechin2-(48)-epigallocatechin; taranoside A - [epigallocatechin gallate]-7-0-[-(16)--D-Glcp]3-(48)-[epigallocatechin-(48)-epigallocatechin]2-(48)-gallocatechin; and taranoside B - [epigallocatechin gallate]-7-O-[-(16)--D-Glcp]4-(48)-[epigallocatechin-(48)-epigallocatechin]2-(48)-epigallocatechin-(48)-[epigallocatechin gallate).Institute of the Chemistry of Plant Substances, Uzbekistan Republic Academy of Sciences, Tashkent. Translated from Khimiya Prirodnykh Soedinenii, No. 1, pp. 59–67, January–February, 1992  相似文献   

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