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1.
The holothurianEupentacta pseudoquinquisemita Deichmann collected in Kraternaya Bay, Ushishir Islands has yielded two triterpene pentaosides — the previously known cucumarioside C2, and cucumarioside H, which is a new glycoside. With the aid of13C NMR spectroscopy and solvolytic desulfation its structure has been determined as 6-acetoxy-3-([3-O-methyl--D-xylopyranosyl-(1 3)--D-glucopyranosyl-(1 4)] [-D-xylopyranosyl-(1 4)] [-D-xylopyranosyl-(1 2)]--D-quinovopy-ranosyl-(1 2)-(4-O-sulfato--D-xylopyranosyloxy)holosta-7,22,24(trans)-triene. Cucumarioside H was also identified inEupentacta (=Cucumaria)fraudatrix from Posyet Bay, Sea of Japan.Pacific Ocean Institute of Bioorganic Chemistry, Far Eastern Branch, USSR Academy of Sciences, Vladivostok. Translated from Khimiya Prirodnykh Soedinenii, No. 2, pp. 221–225, March–April, 1988.  相似文献   

2.
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   

3.
Summary The chemical structures of two new steroid glycosides from the leaves ofPolygonatum latifolium have been shown. Polygonatoside E is 3-[0--D-glucopyranosyl-(1 3)-0--D-glucopyranosyl-(1 4)-0--d-galactopyranosyl-(1 3)--D-glucopyranosyloxy]-(25R)-spirost-5-ene, and protopolygonatoside E is 26--D-galactopyranosyl-(1 3)--D-glucopyranosyloxy]-(25R)-furost-5-en-22-ol.Institute of Chemistry, Academy of Sciences of the Moldavian SSR, Kishenev. Translated from Khimiya Prirodnykh Soedinenii, No. 3, pp. 350–354, May–June, 1978.  相似文献   

4.
A new hederagenin pentaoside — glycoside L-6d — has been isolated from the leaves of common ivyHedera helix L., fam. Araliaceae, and its structure has been determined by using various NMR-spectroscopic methods. Glycoside L-6d is hederagenin 3-O-[O--L-rhamnopyranosyl-(14)-O--D-glucopyranosyl-(16)-O--D-glucopyranosyl-(14)-O--L-rhamnopyranosyl-(12)--L-arabinopyranoside.Simferopol' State University. Translated from Khimiya Prirodnykh Soedinenii, No. 6, pp. 746–752, November–December, 1994.  相似文献   

5.
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   

6.
Summary Two triterpene glycosides — caulosides b and c — have been isolated from a methanolic extract of the leaves ofCaulophyllum robustum maxim. Cauloside b has been identified as hederagenin 3--L-rhamnopyranosyl-(12)--L-arabinopyranoside, while cauloside c has the structure of hederagenin 3-0--L-arabinopyranosyl(13)--L-pyranosyl-(12)--L-arabinopyranoside.Pacific Ocean Institute of Bioorganic Chemistry, Far Eastern Scientific Center of the Academy of Sciences of the USSR, Vladivostok. Translated from Khimiya Prirodnykh Soedinenii, No. 2, pp. 174–176, March–April, 1979.  相似文献   

7.
Conclusions It has been established that patrinoside D1 is the -D-glucopyranosido(13) -D-xylopyranosido(12) -L-rhamnosido(14)--D-xylopyranoside (13) of oleanolic acidKhimiya Prirodnykh Soedinenii, Vol. 5, No. 2, pp. 84–89, 1969  相似文献   

8.
To obtain the kinetic curves of thermal decomposition of ammonium nitrate occurring together with decomposition of metal nitrates contained in a mixture, the ammonia contents evolved from samples heated under thermoanalytical conditions were determined by the Kjeldahl method.
Zusammenfassung Der aus unter thermoanalytischen -Bedingungen erhitzten Proben freigesetzte Ammoniakgehalt wird durch das Kjeldahlverfahren bestimmt, um die kinetischen Kurven der thermischen Zersetzung von Ammoniumnitrat zusammen mit der Zersetzung von Metallnitraten in Gemischen zu erhalten.

, , , .
  相似文献   

9.
Summary Various routes for the synthesis of the methyl ether of d,l-estrone (XI) and of d,l-estrone itself (XIII) have been investigated. The best results were obtained by synthesis according to the route IV V VI I X XI XIII, when the yield of the methyl ether of d,l-estrone (XI) was 25% and that of d,l-estrone 13%, calculated on the basis of 6-methoxytetralone.Khimiya Prirodnykh Soedinenii, Vol. 1, No. 3, pp. 172–180, 1965  相似文献   

10.
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   

11.
In an attempt to clarify the origin of the dual phosphorescence in phenyl alkyl ketones, we have made some calculation (within the C.I.P.S.I. method in an excitonic scheme) to elucidate the conformation of both ground states and excited states of propiophenone. Our calculations have shown the presence of two stable isomers in the ground state, first n * state, and first * singlet and triplet states. So our work suggests that the origin of the dual phosphorescence of propiophenone could be related to the conformational change of the molecule in the n * state, because the most stable conformations in the n * state and in the ground state are different.  相似文献   

12.
Catalytic activities for CO oxidation of a series of LaMeO3(Me3+=V3+, Cr3+, Mn3+, Fe3+, Co3+, Ni3+) perovskite-type oxides were measured. Maxima for Mn3+ and Co3+ were found. The relation between local symmetry of solid surfaces and chemisorption and catalysis is discussed.
, LaMeO3 (Me+3=V+3, Cr+3, Mn+3, Fe+3, Co+3, Ni+3) CO. Mn+3 Co+3. , .
  相似文献   

13.
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   

14.
Bioaccumulation of six metals (Cu2+, Cu+, Mo6+, Mn2+, V5+, Ni2+) and their combinations by algaScenedesmus quadricauda was determined by using radio nuclide X-ray fluorescence (RXFA). The metals were added into the cultivation medium in concentrations corresponding with EC50 value for each metal. The obtained results indicate that Ni2+, Cu2+ and Cu+ were accumulated in high amounts (20%, 17.5% and 15.19%) the Mo6+ ion (<0.2%) was accumulated in the lowest amount. For metal-metal interactions in accumulation of metal ions by algaS. quadricauda three types of answers were determined: inhibition (MoCu2+, Ni, Mn, V; VNi, Mn; MnNi, Cu2+, Cu+; Cu+Ni; Cu2+Ni; NiMn, V), enhancement (VCu+; Cu2+Mn;Cu+V, Mn; MnV; NiCu2+, Cu+) and neutral effect (VMo; Cu2+Mo; Cu+Mo; MuMo; NiMo).  相似文献   

15.
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   

16.
The synthesis of the 17(20)-16 analog of natural chiogralactone is described. Attempts to introduce a 6-oxo group directly into the -lactone proved unsuccessful, since the first stage — saponification — took place with the formation of three products: the 3-hydroxy--lactone, the 3-hydroxy-20(22)-lactone, and the 15,17(20)-dienoic acid. The synthesis of the desired compound was effected from the ethyl ester of the 5,16-dienoic acid by the scheme 3-acetate3-tosylate6-hydroxy-3,5-cyclosteroid6-oxo-3,5-cyclosteroid6-oxo-5H--lactone. It has been shown that the cyclopropane ring in the 3,5-cyclosteroid -lactone is extremely stable under the conditions of acid treatments.N. D. Zelinskii Institute of Organic Chemistry, Academy of Sciences of the USSR, Moscow. Translated from Khimiya Prirodnykh Soedinenii, No. 2, pp. 184–187, March–April, 1981.  相似文献   

17.
A wide range of halogen containing reagents (metal halides, oxyhalides, acid halides, etc.) are found to interact from the gas phase with exchange ions of zeolites and to effect dealumination at elevated temperatures. The incorporation of extraneous ions into the framework by this technique is not impossible theoretically. The importance of the method in the preparation of dealuminated and/or metal containing catalysts is discussed.
, , ( , , ), , . . / , .
  相似文献   

18.
A modern kinetic evaluation method for nonisothermal reactions measured with TG or DSC is presented. The obtained kinetic data are the basis for computation of a reaction process under any condition, e.g. isothermal or adiabatic. The measurements were performed on a Mettler TA3OOO system with built-in evaluation software. Mainly the following reactions are discussed: polyaddition of an epoxy premix and pyrolysis of polystyrene. To judge the reliability of the results, 4 check procedures are recommended.
Zusammenfassung Es wird eine moderne kinetische Auswertungsmethode für durch TG oder DSC verfolgte nichtisotherme Reaktionen vorgestellt. Die erhaltenen kinetischen Daten stellen die Basis der Berechnung der Reaktionsprozesse unter jeder, z.B. isothermer oder isobarer Bedienung dar. Die Messungen wurden mit dem Mettler-System TA3000 mit Auswertungs-software ausgeführt. In erster Linie werden die folgenden Reaktionen diskutiert: Polyaddition eines Epoxy-Vorgemisches, Pyrolyse von Polystyrol. Zur Beurteilung der Zuverlässigkeit der Ergebnisse werden 4 Testverfahren empfohlen.

, . - , , . TA 3000 . - . .
  相似文献   

19.
Most optimized vitreous electrolytes are obtained by doping an oxide glass with a salt (MX); the resulting substance has an increased ionic conductivity, but a reduced thermal stability. On the other hand, this paper shows that it is possible to obtain vitreous electrolytes with enhanced electrical and thermal performances by mixing two glass formers. This phenomenon may be called the mixed anion effect. The Ag2OB2O3P2O5 system is shown to offer a very interesting example of such a phenomenon.
Zusammenfassung Optimale glasartige Elektrolyte werden durch Dopen eines Oxydglases mit einem Salz (MX) erhalten; die Produkte weisen eine erhöhte ionische Leitfähigkeit, jedoch auch eine verminderte thermische Stabilität auf. Andererseits wird gezeigt, daß glasartige Elektrolyte mit besseren elektrischen und thermischen Eigenschaften durch Mischen von zwei Glasbildnern erhalten werden können. Für dieses Phänomen wird die Bezeichnung mixed anion effect in Vorschlag gebracht. Es wird gezeigt, daß das System Ag2OB2O3P2O5 ein sehr interessantes Beispiel dieses Phänomens bietet.

MX. , . . . , Ag2O2325 .


The NMR data were collected at the Regional NMR Center of the Colorado State University (Fort Collins, Co, USA), funded by NSF Grant CHE-8208821). This research was funded in part by the Italian Department of Education (MPI 40%).  相似文献   

20.
Two new steroid glycosides of the spirostan series have been isolated from the fruit ofAllium cepa L. (family Liliaceae): alliospirosides C and D. On the basis of chemical transformations and spectral characteristics it has been established that the aglycon of both glycosides is a new steroid sapogenin — cepagenin — having the structure of (24S,25R)-spirost-5-ene-1,3,24-triol. Alliospirosides C and D are cepagenin 1-O-[O--L-rhamnopyranosyl-(12)-L-arabinopyranoside] and 1-O-[O--L-rhamnopyranosyl-(12)-O--D-galactopyranoside], respectively.Institute of the Chemistry of Plant Substances, Uzbek SSR Academy of Sciences, Tashkent. Translated from Khimiya Prirodnykh Soedinenii, No. 6, pp. 843–849, November–December, 1987.  相似文献   

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