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1.
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   

2.
The Hückel approximation in MO LCAO is used to show that the anion system of cyclopent-4-ene-1,3-dione should have two * transitions: a weak one at long wavelengths, NV1, and a strong one at short wavelengths, C=C(1,3)V1. An ethylene, phenyl, or acyl group at position 2 gives rise to a new strong band, NC=C(2), Nbenz, or NC=O (2). A p-nitrophenyl group at position 2 gives rise to a strong NNO2 band, which overlaps the weak NV1 band, while the Nbenz band becomes weak and is virtually lost from the spectrum.  相似文献   

3.
Seeds ofFatsia japonica(Araliaceae) afforded the known hederagenin 3-O--D-glucopyranosyl-(12)-O--L-arabinopyranoside and the new triterpene glycoside D 2 , for which the structure hederagenin 3-O--D- galactopyranosyl-(12)-O--L-arabinopyranoside was proposed based on chemical methods and NMR spectroscopy  相似文献   

4.
From the leaves of Algerian ivyHedera canariensis Willd. (fam. Aralaceae) we have isolated 13 triterpene glycosides: the 3-O--L-arabinopyranosides of oleanolic acid (A), of echinocystic acid (B1), and of hederagenin (B2); the 3-O-[O--L-rhamnopyranosyl-(2)--L-arabinopyranoside]s of oleanolic acid (C), of echinocystic acid (D), and of hederagenin (E1); the 3-O--L-rhamnopyranoside] 28-O-[O--L-rhamnopyranosyl-(14)--gentiobioside of hederagenin (G1); the 3-O-[O--L-rhamnopyranosyl-(12)--L-arabinopyranoside] 28-O--gentiobioside of hederagenin (G3); the 3-O-[O--L-rhamnopyranosyl-(12)--L-arabinopyranoside] 28-O-[O--L-rhamnopyranosyl-(14)--gentiobioside]s of oleanolic acid (G2), of echinocystic acid (H1), and of hederagenin (H2); the 3-O-[O--L-rhanmopyranosyl-(12)--D-glucopyranoside] 28-O-(O--L-rhamno-pyranosyl-(14)--gentiobioside] of hederagenin (H2); and the 3-O-(O--L-rhamnopyranosyl-(12)-O-gentiobiosyl)-O-(14)--L-rhamnopyranosyl-(12)-a-L-arabinopyranoside] of hederagenin (G4). The structures of the substances isolated have been established on the basis of chemical transformations and13C NMR spectroscopy.Translated from Khimiya Prirodnykh Soedinenii, No. 3, pp. 377–383, May–June, 1996. Original article submitted December 3, 1995.  相似文献   

5.
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   

6.
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   

7.
    
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   

8.
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   

9.
The previously known glycosides 3-O--L-arabinopyranosyl-28-O-[-L-rhamnopyranosyl-(14)-O--D-glucopyranosyl-(16)-O--D-glucopyranosyl]hederagenin and 3-O-[-L-rhamnopyranosyl-(12)-O--L-arabinopyranosyl]-28-O-[-L-rhamnopyranosyl-(14)-O--D-glucopyranosyl-(16)-O--D-glucopyranosyl]hederagenin and the new triterpene glycoside tauroside St-H1 — 3-O--D-glucopyransyl-28-O-[-L-rhamnopyranosyl-(14)-O--D-glucopyranosyl-(16)-O--D-glucopyranosyl]hederagenin — have been isolated from the stems ofHedera taurica Carr.M. V. Frunze Simferopol' State University. Translated from Khimiya Prirodnykh Soedinenii, No. 4, pp. 571–579, July–August, 1993.  相似文献   

10.
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   

11.
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   

12.
Summary The interaction of copper(II) salts with the imidazole-containing disulphide 5-(1,2,5-dithiazaepan-5-ylmethylene)-4-methyl-2-ethyl imidazole (MAMI) in MeOH have been investigated. The 11 Cu(ClO4)2MAMI system exhibited a single ligand field band at ca. 12200cm-1, an intense shoulder at ca. 31500 cm-1 and a less intense split feature at 24400 and 25300cm-1 assignable to S() CuII and S() CuII charge transfer (CT) transitions, respectively. The e.p.r. parameters suggested the presence of a CuN2SO chromophore, however; the 11 Cu(NO3)2MAMI system did not exhibit a S CuII CT band and the g value was comparatively high. An electrochemical study of the 11 Cu(ClO4)2MAMI system in MeOH revealed that the copper-disulphide interaction, though weaker, would confer a high redox potential as well as reversibility, similar to the copper-thioether interaction.  相似文献   

13.
Configuration interaction (CI) studies of ground, n *, * * electronically excited states are reported for pyridine N-oxide. The transition energy to the lowest * excited 1 B 2 state is calculated at 4.35 eV, compared to the experimental spectrum range of 3.67–4.0 eV. This state lies below the lowest n * excited 1 A 2 state calculated at 4.81 eV above the ground state. The only experimentally reported triplet state at 2.92 eV above the ground state is predicted to be the 3 A 1 (*) state. The calculated energy lies at 3.27 eV. Numerous other high-lying singlet states as well as the triplet states have also been calculated. The intramolecular charge transfer character of the ground and the excited states have been studied in terms of the calculated dipole moment and other physical properties.  相似文献   

14.
Stem bark ofTetrapanax papyriferumC. Koch., Araliaceae, yielded new triterpene glycosides 28-O--L-rhamnopyranosyl-(14)-O-(6-O-acetyl--D-glucopyranosyl)-(16)-O--D-glucopyranosyl esters of the 3-O-[-D-glucopyranosyl-(13)-[-D-galactopyranosyl-(12)]-O--L-arabinopyranosides of oleanolic and echinocystic acids. The structures of these substances were established using chemical and physicochemical methods  相似文献   

15.
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   

16.
Conclusions The structure of leontoside D-a hederagenin pentaoside-has been established. The O-glycosidic moiety of leontoside D is O--D-glucopyranosido-(1 4)-O--L-arabopyranose, and the O-acyl moiety is O--L-rhamnopyranosido-(1 4)-O--D-glucopyranosido-(1 6)-O--D-glucopyranose.Khimiya Prirodnykh Soedinenii, Vol. 4, No. 3, pp. 153–158, 1968  相似文献   

17.
3, 5-Dibromocomanic acid (3, 5-dibromo- -pyrone -2-carboxylic acid) VI and its ethyl ester, hitherto not described in the literature, are synthesized by the following route: diethyl acetonedioxalate (I) diethyl dibromochelidonate (III) (mono) ethyl dibromochelidonate (IV) diethyl 3, 5-dibromocomanate (V) VI. Direct bromination of diethyl bromochelidonate gives the ester III. 6-Bromocomenic acid and its ethyl ester are prepared, as well as 2-bromo-3-hydroxy - -pyrone. Bromocomanic acid (x-bromo--pyrone-2-carboxylic acid) XVI is synthesized by the following route: I (mono) ethyl chelidonate ethyl comanate comanic acid XVI. Oxonium salts are obtained: acid sulfates of comanic acid and ethyl comanate.For Part VII [1].  相似文献   

18.
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   

19.
Summary 1. Derivatives of cellulose containing 3, 6-anhydro rings have been synthesized by the following route: cellulose 6-O-tritylcellulose 6-O-trityl-2, 3-di-O-acetylcellulose 2, 3-di-O-acetylcellulose 6-O-tosyl-2, 3-di-O-acetylcellulose 3, 6-anhydrocellulose.2. The composition of the 3, 6-anhydrocellulose has been studied by exhaustive acetylation, nitration, and periodate oxidation, and also by IR spectroscopy.Khimiya Prirodnykh Soedinenii, Vol. 2, No. 6, pp. 372–375, 1966  相似文献   

20.
The thermal desorption of atomic oxygen during the transformations BiO2 – x -Bi2O3 -Bi2O3is shown to be due to the removal of overstoichiometric oxygen from the bulk of -Bi2O3. Oxygen formed at the first stage is desorbed in a molecular form. The maximum desorption rate of atomic oxygen is found before the phase transformation -Bi2O3 -Bi2O3. The activation energy of the diffusion of excess oxygen in the -Bi2O3lattice is 30 kcal/mol.  相似文献   

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