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1.
A new ecdysteroid (rhapisterone B) has been isolated from the seeds ofRhaponticum cathamoides (Willd.) Iljin. (familyCompositae). It has been shown that it is 2, 3, 11, 14, 20R, 24-hexahydroxy-5-cholest-7-en-6-one.Institute of the Chemistry of Plant Substances, Uzbek Academy of Sciences, Tashkent. Translated from Khimiya Prirodnykh Soedinenii, No. 6, pp. 806–808, November–December, 1991.  相似文献   

2.
A new steroid glycoside of the spirostan series, anzuroside, has been isolated from the collective fruits of the cocultivatedAllium suvorovii Rgl. andA. stipitatum Rgl. (family Liliaceae, local name anzur). Enzymatic cleavage of the glycoside has given the previously undescribed steroid sapogenin anzurogenic C, which has the structure of (24S, 25S)-2,3,5,24-tetrahydroxy-5-spirostan-6-one. Anzuroside is the 24-O--D-glucopyranoside of anzurogenin C.Institute of the Chemistry of Plant Substances, Uzbek SSR Academy of Sciences, Tashkent. Translated from Khimiya Prirodnykh Soedinenii, No. 4, pp. 505–510, July–August, 1989.  相似文献   

3.
Summary From the roots ofSeseli grandivittatum, together with -sitosterol and (–)-3R-decursinol, found in nature for the first time, and its angelate, we have isolated two new compounds which we have called grandivittin and grandivittinol.On the basis of IR, PMR, and mass spectra and chemical transformations, the structure of 3-senecioyloxy-3,4-dihydro-3R-xanthyletin is proposed for grandivittin, and 7-hydroxy-6-(3-hydroxy-2-senecioyloxyisopentyl) coumarin for grandivittinol.Leningrad Sanitary-Hygienic Medical Institute. Translated from Khimiya Prirodnykh Soedinenii, No. 5, pp. 640–646, September–October, 1977.  相似文献   

4.
The stoichiometry of the oxidation of rhamnose by periodate has been studied using a method based on the determination of iodate. Conditions have been found under which one mole of rhamnose stoichiometrically reduces six moles of periodate. An amplification method for the titrimetric determination of rhamnose is proposed in which one mole of rhamnose reacts with 6 moles of periodate with the formation of six moles of iodate, which is equivalent to 18 moles of triiodide, in the titration of which 36 gram-equivalents of sodium thiosulfate are consumed. The method is distinguished by high sensitivity and accuracy. The relative standard deviation in the determination of 2–3.5 mg of rhamnose does not exceed 0.5–1%.Biokhimreaktiv Scientific Production Association. All-Union Scientific-Research Institute of Applied Biochemistry, Olaine. Translated from Khimiya Prirodnykh Soedinenii, No. 1, pp. 21–24, January–February, 1984.  相似文献   

5.
The structure of a new cycloartane glycoside, cycloaraloside B, isolated from the roots ofAstragalus amarus Pall. (Leguminosae) has been established on the basis of chemical transformations and spectral characteristics: it is 20R,24S-epoxycycloartane-3,6,16,25-tetraol 3-O-[O--L-rhamnopyranosyl-(12)-(6-O-acetyl--D-glucopyranoside)].Institute of Chemistry of Plant Substances, Uzbekistan Academy of Sciences, Tashkent. Translated from Khimiya Prirodnykh Soedinenii, No. 5, pp. 528–531, September–October, 1992.  相似文献   

6.
A new genin of the spirostan series — anzurogenin B having the structure of 2,5-epoxy-(25R)-spirostan-3,6-diol — has been isolated form the collective fruit of the cocultivatedAllium suvorovii Rgl. andAllium stipitatum Rgl. (family Liliaceae).Institute of the Chemistry of Plant Substances, Uzbek SSR Academy of Sciences, Tashkent. Translated from Khimiya Prirodnykh Soedinenii, No. 2, pp. 218–221, March–April, 1988.  相似文献   

7.
Conclusions Based on the data of selective cleavage, methylation, and oxidation with CrO3 it was shown that the repeating unit of the polysaccharide chain of the liposaccharide from type 6Sh. dysenteriae is the trisaccharide-D-N-acetylgalactosaminyl-(1–3)--D-galactopyranosyl-(1–6)--D-glucopyranose, to the galactose residue of which is attached an unindentified acid component in the 4 position.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 10, pp. 2302–2308, October, 1975.The authors express their gratitude to G. V. Vikha for graciously supplying the-hexosaminidase and to B. M. Zolotarev for taking the mass spectra.  相似文献   

8.
The roots ofPolygonum coriarum have yielded two oligomeric proanthocyanidins, T1 and T2, and their structures have been established: 3-O-galloyl-7-O-[O-(6-O-galloyl)--D-glucopyranosyl]-(–)-epigallocatechin-(4-8)-(–)-epicatechin-(4-8)-(–)-epicatechin-(4-8)-(–)-epigallocatechin 3-O-gallate (T1) and (–)-epicatechin-(4-8)-[3-O-galloyl-(–)-epigallocatechin]-(4-8)-(–)-epicatechin-(4-8)-(+)-catechin (T2).The material of this paper were presented at the IInd International Symposium on the Chemistry of Natural Compounds (SCNC, Eskisehir, Turkey, October 22–24, 1996).Translated from Khimiya Prirodnykh Soedinenii, No. 4, pp. 588–593, July–August, 1977.  相似文献   

9.
The kinetics of the oxidation of thiourea to sulfate by octacyanomolybdate(V) and octacyanotungstate(V) ions have been studied in an alkaline medium. The reactions are first order with respect to thiourea, octacyanomolybdate(V) or octacyanotungstate(V), hydroxide and sodium ions. The observed fourth order rate constants are ca. 1.20×107 and ca. 9.80×103 M–3 min–1 for oxidation by Mo(CN) 8 3– and W(CN) 8 3– , respectively at 298K. A reaction mechanism is proposed.
(V) (V) . , (V) (V), . 1,2·107 9,8·103 M–3 –1 Mo(CN)8 –3 W(CN)8 –3 298 . .
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10.
The collective fruit of the cocultivatedAllium suvorovii Rgl. andA. stipitatum Rgl. (familyLiliaceae) has yielded a new genin of the spirostan series — anzurogenin A, which is 2,3,5-trihydroxy-(25R)-spirostan-6-one.Institute of the Chemistry of Plant Substances, Academy of Sciences of the Uzbek SSR, Tashkent. Translated from Khimiya Prirodnykh Soedinenii, No. 1, pp. 68–73, January–February, 1988.  相似文献   

11.
The changes in surface area and density which occur during the decomposition of eight nickel oxysalts have been reported. Surface area peaks were observed in the temperature range 473 K to 673 K. An equation relating to the number of product particles (n) produced from a single particle of original material has been derived. Logn was shown to vary linearly with temperature, wheren is the number of product particles formed from one original reactant particle.
Zusammenfassung Es wird über die Veränderungen der Oberfläche und Dichte berichtet, welche bei der Zersetzung von acht Nickeloxysalzen auftreten. Oberflächenpeaks wurden im Temperaturbereich von 473 K bis 673 K beobachtet. Eine Gleichung wurde abgeleitet, welche sich auf die Zahl (n) der sich aus einem einzigen Partikel der Ausgangssubstanz bildenden Produktpartikel bezieht. Es wurde bewiesen, daß sich logn linear zur Temperatur ändert, wobein die Zahl der sich aus einem reagierenden Ausgangspartikel bildenden Produktpartikel ist.

Résumé Etude des changements de surface spécifique et de densité pendant la décomposition de huits oxysels du nickel entre 473 K à 673 K. En désignant parn le nombre de particules issues d'une particule unique du matériau initial, on montre que logn varie linéairement avec la température.

8 - , . , , 473–673 . , (), . logn .
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12.
The structure of psolusoside B — a minor triterpene oligoglycoside from the holothurianPsolus fabricii and the main glycoside fromPsolus sp. has been determined by the methods of partial acid hydrolysis, methylation,13C NMR, and FAB mass spectrometry as 20S-acetoxy-3-{2-O-[O--D-glucopyranosyl-(1 4)-O--D-glucopyranosyl]-4-O-(6-O-sulfato--D-glucopyranosyl)--D-xylo-pyranosyloxy}holosta-7,25-diene-18,16-carbolactone. 3-[O-(3-O-Methyl-6-O-sulfato--D-glucopyranosyl)-(1 3)-O-(6-O-sulfato--D-glucopyranosyl)-(1 4)-O--D-quinovopyranosyl-(12)--D-xylopyranosyloxy]holosta-9(11),25-dien-16-one (psolusoside A), known previously forPsolus fabricii, has been identified in a holothurian —Psolus sp. — from Kraternaya Bay (island of Ushishir).Pacific Ocean Institute of Bioorganic Chemistry, Far Eastern Branch, Academy of Sciences of the USSR, Vladivostok. Translated from Khimiya Prirodnykh Soedinenii, No. 3, pp. 361–368, May–June, 1989.  相似文献   

13.
Under the experimental conditions [DMSO]T [CeIV]T [Os]T the kinetics of oxidation of dimethylsulfoxide (DMSO) to dimethylsulfone (DMSO2) have been followed at different temperatures (40–55°C) in 1.0 mol dm–3 sulfuric acid media. The rate of disappearance of [CeIV] shows a first-order dependence on both [Os]T and [DMSO]T and zeroth-order kinetics with respect to [CeIV]. The suggested mechanism involves oxidation of DMSO by OsVIII in a rate-determining step through an outer-sphere mechanism, followed by rapid regeneration of OsVIII by CeIV from OsVI. The rate law conforms to: –d[CeIV]/dt=k0=k[Os]T[DMSO]T. The values of k and the activation parameters are: 102k=(4.9 ± 0.10) mol–1 dm3 s–1 at 40°C, [H2SO4] =1.0 mol dm–3;H=58±3kJmol–1, S= –88 ±5JK–1mol–1.  相似文献   

14.
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   

15.
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   

16.
Using the method of analytical GLC in a glass capillary column, the compositions have been studied of the volatile fractions of the oleoresins of five species of conifers:Larix decidua,Pinus strobus,Pinus mugo,Picea excelsa, andPinus abies. In the oleoresins 21 monoterpene and 22 sesquiterpene compounds were identified from their relative retention times and with the aid of additives. The main components of the volatile fractions of the oleoresins were - and -pinenes and 3-carene among the monoterpenes, and longifolene caryophyllene, - and -cadinenes and -murolene among the sesquiterpene compounds. The quantitative analysis of the fractions was carried out by the method of internal normalization from averaged correlation coefficients.Institute of Organic Chemistry, Siberian Branch, Academy of Sciences of the USSR, Novosibirsk. Translated from Khimiya Prirodnykh Soedinenii, No. 5, pp. 629–632, September–October, 1990.  相似文献   

17.
The new phenolic glycoside paeonovicinoside (methyl salicylate 6--L-arabino-pyranosyl--D-glucopyranoside), and also paeoniflorin, -sitosterol, benzoic acid, and gallic acid and its methyl ester have been isolated from the roots ofPaeonia anomala.All-Union Scientific-Research Institute of Medicinal Plants Scientific Production Combine, Moscow. D. I. Ul'yanov Kuibyshev Medical Institute. All-Union Scientific-Research Institute of Pharmacy, Moscow. Translated from Khimiya Prirodnykh Soedinenii, No. 1, pp. 55–59, January–February, 1992.  相似文献   

18.
A new withasteroid — vamonolide — has been isolated from the epigeal part ofPhysalis angulata L. (Solanaceae). On the basis of spectral characteristics, its structure has been established as 5,14-dihydroxyl-l-oxo-6,7-epoxy-20R,22R-with-2-enolide.Institute of the Chemistry of Plant Substances, Uzbek SSR Academy of Sciences, Tashkent. Translated from Khimiya Prirodnykh Soedinenii, No. 6, pp. 856–858, November–December, 1987.  相似文献   

19.
Summary Six bases have been isolated from the leaves of the plantZiziphus jujuba Mill. family Rhamnaceae, cultivated in Tashkent: coclaurine, which has been isolated previously, and isoboldine, norisoboldine, asimilobine, which have been isolated for the first time, and the new juziphine and juzirine. It has been established that juziphine has the structure of 8-hydroxy-1R-(4-hydroxybenzyl)-7-methoxytetrahydroisoquinoline, and juzirine that of 7-hydroxy-1-(4-hydroxybenzyl)-6-methoxyisoquinoline.Juziphine has also been isolated from the epigeal part ofCorydalis gortschakovii.Institute of the Chemistry of Plant Substances, Academy of Sciences of the Uzbek SSR, Tashkent. Translated from Khimiya Prirodnykh Soedinenii, No. 2, pp. 239–243, March–April, 1977.  相似文献   

20.
The sodium salt of 3-sulfooxythornasterol A and a new glycoside — the disodium salt of 3-sulfooxy-6-[-D-4-sulfooxyquinovopyranosyloxy]-5-pregn-9(11)-en-20-one (cheliferoside LI) has been isolated from the starfishLethasterias nanimensis chelifera. The structures of the compounds have been established by spectral methods.Pacific Ocean Institute of Biochemistry, Far Eastern Branch, Academy of Sciences of the USSR, Vladivostok. Translated from Khimiya Prirodnykh Soedinenii, No. 4, pp. 520–523, July–August, 1991.  相似文献   

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