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1.
From a methanolic extract of the bulbs ofAllium turcomanicum Rgl. we have isolated a new furostanol glycoside, turoside C (I). An acid hydrolysate was found to contain the aglycone — neoagigenin (II) — and the sugars D-xylose, D-glucose, and D-galactose in a ratio of 1:4:1. The structure of the furostanol (I) has been established by methylation, enzymatic hydrolysis, and oxidative cleavage, and also by the oxidative cleavage of (II), as (25S)-5-furostan-2,3,6,22,26-pentaol 26-O--D-glucopyranoside 3-O-{[O--D-xylopyranosyl-(13)]-[O--D-glucopyranosyl-(12)-O--D-glucopyranosyl-(12)]-O--D-glucopyranosyl-(14)--D-galacto-pyranoside}.Institute of the Chemistry of Plant Substances, Academy of Sciences of the Uzbek SSR, Tashkent. Translated from Khimiya Prirodnykh Soedinenii, No. 4, pp. 514–522, July–August, 1979.  相似文献   

2.
Triterpene glycosides from Pulsatilla chinensis   总被引:1,自引:0,他引:1  
Four triterpene glycosides were isolated from the roots of Pulsatilla chinensis (Bunge) Regel (Ranunculaceae). Two new glycosides, chinensiosides A (1a) and B (2), were identified as 3-O-[-L-rhamnopyranosyl-(12)--L-arabinopyranosyl]-28-O-[-L-rhamnopyranosyl-(14)--D-glucopyranosyl-(16)--D-glucopyranosyl]-3,23-dihydroxylup-20(29)-en-28-oic acid and 3-O-{-L-rhamnopyranosyl-(12)-[-D-glucopyranosyl-(14)]--L-arabinopyranosyl}-28-O-[-L-rhamnopyranosyl-(14)--D-glucopyranosyl-(16)--D-glucopyranosyl]-3,23-dihydroxylup-20(29)-en-28-oic acid. The other two glycosides were identified as previously known hederasaponin C (3) from Hedera helix and glycoside III (4) from Pulsatilla cernua.  相似文献   

3.
Summary Bifunctional methylenebis(diphenylphosphine oxide) (mdpo) on reaction with iron(III) perchlorate forms the complex, [Fe(mdpo)3](ClO4)3 · H2O. This has been characterized through elemental analysis, i.r., far-i.r., u.v. and visible spectroscopy and by x-ray diffraction, magnetic moment, molar conductance and e.s.r. data. The e.s.r. spectrum consists of five lines with transitions from: ¦–5/2¦–3/2¦–3/2¦–1/2, ¦–1/2¦+1/2¦+1/2¦+3/2 and ¦+3/2¦+5/2 centred at a g-value of 2.00. On the basis of these studies, a chelated octahedral structure has been assigned to the cation, [Fe(mdpo)3]3+.  相似文献   

4.
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   

5.
Short-wavelength nSe * and long-wavelength nSe * bands are observed in the UV spectra of saturated trialkylarsine selenides in the near-UV region. The nx * band in going from arsine selenides to arsine sulfide and then to arsine oxides is shifted hypsochromically, as in the corresponding phosphorus compounds. The nx * band is only slightly sensitive to the chalcogen. Saturated trialkylarsines, in contrast to alkylphosphines, absorb in the near UV region (the nAs * band is at 208 nm).Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 4, pp. 940–942, April, 1990.  相似文献   

6.
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   

7.
The activation energy, E, of simple catalytic reactions over 3d-oxides and the initial heats of adsorption, Qads, of gases on metals are related in a complex way to the enthalpy of formation of oxides and to the electronegativity of the gases involved in the processes.
, , 3d- , Qads, , .
  相似文献   

8.
A new glycoside (cyclofoetoside B) (I) has been isolated from the epigeal part of the plantThalictrum foetidum L. (Ranunculaceae). On the basis of chemical transformations and with the aid of physicochemical characteristics it has been established that cyclofoetoside B is 24S-cycloartane-3, 16, 24, 25, 29-pentaol 3-O--L-arabinopyranoside 16-O-[O--L-rhamnopyranoside-(1 6)--D-glucopyranoside], C47-H80O17, mp 194–197°C (methanol); [] D 24 +15.7 ± 2° (c 0.88; pyridine). The enzymatic hydrolysis of (I) has yielded cyclofoetigenin B (III), 24S-cycloartane-3,16,24,25,29-pentaol 16-O--D-glucopyranoside, (IV), C36H62O10, mp 223–225°C (acetone), [] D 24 +37 ± 2° (c 0.97; methanol) and 24S-cycloartane-3,16,24,25,29-pentaol 16-O-[O--L-rhamnopyranosyl-(1 6)--D-glucopyranoside, C42H72O14, mp 229–231°C (methanol), [] D 30 +41 ± 2° (c 0.7; methanol). Details of the IR and1H and13C NMR spectra of the compounds are given.Irkutsk Institute of Organic Chemistry, Academy of Sciences of the USSR. Institute of the Chemistry of Plant Substances, Academy of Sciences of the Uzbek SSR, Trashkent. Translated from Khimiya Prirodnykh Soedinenii, No. 3, pp. 341–345, May–June, 1986.  相似文献   

9.
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   

10.
The kinetics of the oxidation of cyclohexanol by molecular O2 catalyzed by Ru(III) and Ru(III)-EDTA complexes has been investigated by oxygen absorption method in the pH range 1.75–3.00 at 30°C (=0.1M KNO3) in a 11 ethanol-water medium. In both cases the reaction was found to be first order with respect to substrate and catalyst concentration. The rate was found to decrease with the decrease of pH in case of Ru(III)-EDTA complex. Ethanol is not oxidized under the reaction conditions. A possible mechanism for the catalytic oxidation of cyclohexanol is proposed.
O2, Ru(III) Ru(III)-EDTA, pH 1,75–3,00 30°C (=0,1M KNO3) - (11). . pH Ru(III)-EDTA. . .
  相似文献   

11.
    
A holostane oligoglycoside — pseudostichoposide A — has been isolated from the holothurianPseudostichopus trachus Sluiter, collected on the oceanic side of the island of Urup (Kurile Islands). Its structure has been established with the aid of13C and1H NMR spectroscopy and partial acid hydrolysis with sulfuric acid in the presence of butanol as 3-{O-(3-O-methyl--D-quinovopyransoyl-(1 3)-O--D-xylopyranosyl-(1 4)-O--D-quinovopyranosyl-(1 2)-[4-O-(sodium sulfato)--D-xylopyranosyloxy]}-holost-7-en-22-one. Its native genin, which has been called urupogenin (3-hydroxyholost-7-en-22-one) was obtained on partial hydrolysis in the form of an individual compound. It is a new holostane derivative.Pacific Ocean Institute of Bioorganic Chemistry, Far Eastern Branch, Academy of Sciences of the USSR, Vladivostok. Translated from Khimiya Prirodnykh Soedinenii, No. 5, pp. 678–684, September–October, 1989.  相似文献   

12.
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   

13.
The chiroptical properties associated with the * transitions in dissymmetric allene systems are calculated and relationships between the chiroptical observables and the stereochemical and electronic structural features of these systems are examined. The calculations are based on the INDO and CNDO/S semiempirical molecular orbital models for the electronic structure of the molecular systems and excited states are constructed in the virtual orbital-configuration interaction approximation. The dipole strengths, rotatory strengths, and dissymmetry factors for the three lowest energy * transitions are computed and reported for eleven chiral allene structures. Relationships between absolute configuration and the signs of the * rotatory strengths are examined and discussed.  相似文献   

14.
Five minor triterpenoids have been isolated from the chloroform-soluble fraction of a methanolic extract ofThalictrum minus by chromatography on silica gel: (I) — oleanolic acid; (II) — oleanolic acid 3-0--L-arabinopyranoside; (III) — oleanolic acid 3-0-[0--D-glucopyranosyl-(1 3)--L-arabinopyranoside]; (IV) — oleanolic acid 3-0-[0--L-rhamnopyranosyl(1 2)-0--D-glucopyranosyl-(1 3)--L-arabinopyranoside]; and (V) — oleanolic acid 28-0--D-glucopyranoside 3-0-[0--D-glucopyranosyl-(1 3)--L-arabinopyranoside]. This is the first time that any of the compounds isolated have been detected in plants of the genusThalictrum. The possibility has been shown of determining the structures of triterpene glycosides on the basis of13C NMR spectroscopy and FAB mass spectrometry without chemical transformations of the glycosides.Irkutsk Institute of Organic Chemistry, Siberian Branch, Academy of Sciences of the USSR. Translated from Khimiya Prirodnykh Soedinenii, No. 1, pp. 107–111, January–February, 1987.  相似文献   

15.
    
Summary 1. The methyl esters of thymidylyl-(5N)-and thymidylyl-(3N)-phenylalanines have been obtained from the mixed anhydrides of the corresponding nucleotides with diphenyl phosphate with yields of 50–60%.2. The esters of the thymidylyl-(PN)- phenylalanines are readily hydrolyzed in an acid medium. The phosphoramide bond in the thymidylylphenylalanines is stable in the pH range from 4 to 12.3. The conversion of the ester of thymidylyl-(3N)-phenylalanine into thymidine-3, 5 cyclic phosphate shows the ease of protonation of the amide nitrogen with the participation of the 5-hydroxyl group and subsequent nucleophilic substitution on the nucleotidic phosphorus atom.Khimiya Prirodnykh Soedinenii, Vol. 2, No. 1, pp. 35–39, 1966  相似文献   

16.
The structure of psolusoside A — the main component of the glycosidic fraction from the holothurianPsolus fabricii Duben et Koren — has been determined as 3-0-[0-(3-0-methyl-6-0-sulfato--D-glucopyranosyl)-(1 3)-0-(6-0-sulfato--D-glucopyranosyl)-(1 4)-0--D-quinovopyranosyl-(1 2)--D-xylopyranosyloxy]holosta-9(11),25-dien-16-one.Pacific Ocean Institute of Bioorganic Chemistry, Far Eastern Scientific Center, Academy of Sciences of the USSR, Vladivostok. Translated from Khimiya Prirodnykh Soedinenii, No. 2, pp. 212–217, March–April, 1985.  相似文献   

17.
From a methanolic extract of the epigeal part ofRhinopetalum stenantherum have been isolated -chaconine (I) and the new glucoalkaloids stenanthine with mp 262–264°C []D 46.5°, C45H73NO15 (II), and stenanthidine with mp 269–271°C, []D –47.5°, C39H63NO11 (III). On the basis of the facts that partial hydrolysis of the trioside (II) formed the biosides (I) and (III), and that on the hydrolysis of the latter the monoside -chaconine was found, it may be assumed that stenanthine has the structure of solanidine 3-0-{[0--D-glucosyl-(1 6)]-[0--L-rhamnosyl-(1 4)]-D-glucoside}, and stenanthidine that of solanidine 3-0-[0--D-glucosyl-(1 6)-D-glucoside].Institute of the Chemistry of Plant Substances, Academy of Sciences of the Uzbek SSR, Tashkent. Translated from Khimiya Prirodnykh Soedinenii, No. 3, pp. 349–356, May–June, 1981.  相似文献   

18.
The structure of the branched polysaccharide glucoarabinogalactan was investigated by periodate oxidation, methylation, and 13C NMR spectroscopy. The main chain consists of -16-bonded galactopyranoses. 12-Bonded D-glucopyranoses and 13-bonded D-galactopyranoses are located on the unreducing ends. There is a short side chain with -13-bonded L-arabinopyranoses.  相似文献   

19.
Summary From a methanolic extract of the inflorescences ofAllium karataviense Rgl. we have isolated a new steroid glycoside of the spirostan series - karatavioside A, which is (25R)-spirost-5-ene-2,3-diol 3-0-{[0--D-xylopyranosyl-(13)-][O--D-glucopyranosyl-(12)-]-0--D-glucopyranosyl-(l4)--D-galactopyranoside}.Translated from Khimiya Prirodnykh Soedinenii, No. 6, pp. 740–746, November-December, 1978. Original article submitted June 30, 1978.  相似文献   

20.
(+)-3-Methyl-3,4-dihydroisoquinoline-1-thione was obtained by sulfuration of (+)-3-methyl-3,4-dihydroisoquinolone with phosphorus pentasulfide or by cyclization of (+)--benzylethyl isothiocyante under the influence of polyphosphoric acid. Measurements of the rotatory dispersion and circular dichroism showed the presence of two positive Cotton effects due to n* and * transitions in the thioamide chromophore, as well as Cotton effects apparently due to * transitions in the aromatic chromophore.Communication XXXV from the series Stereochemical Investigations. See [11] for communication XXXIV.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 1, pp. 94–97, January, 1976.  相似文献   

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