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1.
A new cycloartane glycoside of the cyclostipuloside C series, 3-O--D-xylopyranoside-6,16-di-O--D-glucopyranoside-20S-24R-epoxycycloartan-3,6,16,25-tetraol is isolated from aerial organs of Tragacantha stipulosa Boriss.  相似文献   

2.
60Co -ray radiolysis of cholesterol /3-hydroxy-5-cholestene/ /I/ in the two-phase system /water-ethyl acetate/ and in the presence of air has been studied using TLC and GC methods. The following products were observed in the irradiated mixture: 3, 7-dihydroxy-5-cholestene /II/, G O. 36, 3-hydroxy-7-keto-5-cholestene /III/, G 1.48, 3-hydroxy-7-keto-5-cholestane /IV/, G 0.22, 3,5,6-trihydroxy-5-cholestane /V/, G 0.83, 5,6-epoxy-3-hydroxy-5-cholestane /VIa/, G 0.26, 5,6-epoxy-3-hydroxy-5-cholestane /VIb/, G 0.24, and 2, 3-dihydroxy-5-cholestene /VII/, G 0.22. The dose dependence of the formation of these products shows that the cholesterol derivatives substituted in the position 7 /II–IV/ are formed from a common precursor — the radical Ia. On the other hand, the products of the 5–C=C double bond reactions /V and VI/ are formed independently. Also the product VII is formed independently. A reaction scheme that is in agreement with these results is proposed.  相似文献   

3.
Seeds of Fatsia japonica (Araliaceae) yielded the new glycosides of gypsogenin: 3-O--D-glucopyranosyl-(12)-O--D-glucopyranoside and 3-O--D-galactopyranosyl-(12)-O--D-glucopyranoside. The structures of these compounds were established by chemical methods and NMR spectroscopy.  相似文献   

4.
Summary Three cardiac glycosides have been synthesized from gitoxigenin and D-glucose: gitoxigenin 3-O--D-glucopyranoside, gitoxigenin 16 -O- -D-glucopyranoside, and gitoxigenin 3, 16-di-O- -D-glucoside. The first glycoside, obtained with a yield of 49% on the weight of the initial aglycone, possesses a fairly high biological activity (0.25 mg/kg), while the other two, formed in a yield of about 0.3%, do not possess the action on the heart that is specific for the cardenolides.Khar'kov Chemical and Pharmaceutical Scientific-Research Institute. Translated from Khimiya Prirodnykh Soedinenii, No. 1, pp. 45–49, January, 1971.  相似文献   

5.
The reaction of dibenzylphosphine oxide with O-methyloximes of some ,-unsaturated ketones results in the phosphorylation at the -carbon atom to form methoxyiminophosphine oxides, whereas the reaction of dibenzylphosphine oxide with O-methyloximes of ,-unsaturated aldehydes affords aminodihydrophosphole oxides.  相似文献   

6.
Summary From a methanolic extract of the skins of the bulbs ofAllium giganteum Rgl, a new steroid glycoside has been isolated — aginoside, which is (25R)-5-spirostan-2, 3, 6-triol 3-0-{[0--D-xylopyranosyl-(13)-]-[0--D-glucopyranosyl-(12)]-0--D-glucopyranosyl-(14)-0--D-galactopyranoside}.Institute of the Chemistry of Plant Substances, Academy of Sciences of the Uzbek SSR, Tashkent. Translated from Khimiya Prirodnykh Soedinenii, No. 4, pp. 480–486, July–August, 1976.  相似文献   

7.
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   

8.
From the far-eastern starfishHenricia sp. we have isolated and characterized the new polyhydroxysteroid (24S)-5-cholestane-3,4,6,8,15,24-hexaol and three new glycosides: (24S)-5-cholestane-3,4,6,8,15,24-hexaol 3-O-(2,4-di-O-methyl--D-xylopyranoside) (henricioside H1), 24-methyl-5-cholesta-4,22E-diene-3,6,8,15,16,26-hexaol 3-O-(2,3-di-O-methyl--D-xylopyranoside) (henricioside H2), and the 22,23-dihydro derivative of henricioside H2 (henricioside H3).Pacific Ocean Institute of Bioorganic Chemistry, Far-Eastern Scientific Center, Russian Academy of Sciences, Vladivostok. Translated from Khimiya Prirodnykh Soedinenii, No. 2, pp. 249–253, March–April, 1993.  相似文献   

9.
As the result of a further study of the total alkaloids from the epigeal part ofAconitum turczaninowi we have isolated beiwutine and delcaroline and also a new alkaloid, which has been called turcosine. The structure of turcosine as 6,16-dimethoxy-4-methoxymethyl-1,7,8,10,14-pentahydroxy-N-ethylaconitane has been shown from a study of the IR, mass, PMR, and13C NMR spectra of the alkaloid and of the triacetate obtained from it.Institute of Chemistry, Mongolian People's Republic Academy of Sciences. Institute of the Chemistry of Plant Substances, Uzbekistan Republic Academy of Sciences, Tashkent. Translated from Khimiya Prirodnykh Soedeninii, No. 1, pp. 60–62, January–February, 1993.  相似文献   

10.
Summary With strophanthidin as starting material, 3, 5, 10, l4-tetrahydroxy-19-norandrostan-17-one has been obtained by a five-stage synthesis.  相似文献   

11.
Zusammenfassung Das feste -Carotin ist gegen -Strahlung ziemlich stabil. Bei Bestrahlung unter Sauerstoffbegasung treten deutliche -Carotin-Verluste erst bei der hohen Dosis von 12 Mrad auf; bei Bestrahlung an der Luft werden ähnliche Radiolyseerscheinungen erst durch wesentlich höhere Strahlendosen ausgelöst. Spaltungsprodukte, die bei 12 Mrad und Sauerstoffbegasung auftraten und dünnschichtchromatographisch aufgetrennt werden konnten, waren Isozeaxanthin, -Carotin-5,6-5, 6-diepoxid, -Carotin-5,8-5,8-diepoxid, -Apo-12-carotinal, -Apo-10-carotinal, 3,3,6-Trihydroxy--carotin-5,8-epoxid und Vitamin-A-Alkohol. Es ist bemerkenswert, daß ein Teil der Radiolyseprodukte (z. B. Vitamin-A1-Alkohol, -Apo-12-carotinal und -Apo-10-carotinal) Vitamin-A-Wirksamkeit besitzt.
The -Irradiation of synthetic -carotene. Some physico-chemical and thin-layer chromatographic studies of radiolysis products
Solid -carotene is remarkably stable to -irradiation. In an oxygen atmosphere doses as high as 12 Mrad were required to bring about significant losses of -carotene, whereas in air even larger doses had to be applied in order to effect a comparable degree of radiolysis. Cleavage products which arose in O2 at a dose of 12 Mrad and which could be separated from each other by thin-layer chromatography were isozeaxanthin, -carotene-5,5-5,6-diepoxide, -apo-12-carotenal, -apo-10-carotenal, 3, 3, 6-trihydroxy--carotene-5,8-epoxide and vitamin A1. It is notable that some of the radiolysis products (e.g., vitamin A1, -apo-12-carotenal and -apo-10-carotenal) possess vitamin A activity.


Herrn Prof. Dr.O. Hromatka zum 65. Geburtstag gewidmet.  相似文献   

12.
A glycoside has been isolated from the plantNolina microcarpa S. Wats. (family Dracaenaceae) which has been called nolinofuroside B and has the structure of 6-methoxy-3,5-cyclo-(25S)-furostan-1,22,26-triol 1-O--D-fucopyranoside 26-O--D-glucopyranoside (I). Enzymatic hydrolysis of the bioside (I) yielded nolinospiroside B (III) and nolinogenin (IV). The latter is 6-methoxy-3,5-cyclo-(25S)-spirostan-6-ol, and glycoside (III) is its 1-O--D-fucopyranoside.M. V. Frunze Simferopol' State University. Institute of Chemistry of Plant Substances, Uzbekistan Academy of Sciences, Tashkent. Translated from Khimiya Prirodnykh Soedinenii, No. 2, pp. 218–224, March–April, 1992.  相似文献   

13.
A new ecdysteroid — nusilsterone — has been insolated from the whole plantSilene nutans L. It has been shown that it is 1,2,3,14,20R,22R,24,25-octahydroxy-5--cholest-7-en-6-one.Institute of Chemistry of Plant Substances, Academy of Sciences of the Uzbek SSR, Tashkent. Translated from Khimiya Prirodnykh Soedinenii. No. 4, pp. 522–525, July–August, 1985.  相似文献   

14.
Two new glycosides have been isolated from the roots of the plantAstragalus basineri Trautv. — cyclosiversiosides B and D. It has been shown that cyclosiversioside B is cyclosiversigenin 3-O-(2,3-di-O-acetyl--D-xylopyranoside)-6-O--D-glucopyranoside. Cyclosiversioside D is cyclosiversigenin 3-O-(2-O-acetyl--D-xylopyranoside)-6-O--D-glucopyranoside.Institute of the Chemistry of Plant Substances, Academy of Sciences of the Uzbek SSR, Tashkent. Translated from Khimiya Prirodnykh Soedinenii, No. 2, pp. 188–191, March–April, 1984.  相似文献   

15.
Two new glycosides of the cholestane series (allosides A and B) have been isolated from the fruit of the cocultivatedAllium suvorovii Rgi. andAllium stipitatum Rgl. (family Liliaceae, local name anzur). The acid hydrolysis of both compounds gave a sterol not previously described, which has been called alliosterol and has the structure of (22S)-cholest-5-ene-1, 3, 16, 22-tetraol, and the product of its dehvdration, which is (16S, 22S)-furost-5-ene-1, 3-diol. Alloside A is the 16-O--D-galactopyranoside, and alloside B the 16-O--D-galactopyranoside 1-O--D-glucopyranoside of alliosterol.Institute of Chemistry of Plant Substances, Academy of Sciences of the Uzbek SSR, Tashkent. Translated from Khimiya Prirodnykh Soedinenii, No. 2, pp. 231–241, March–April, 1991.  相似文献   

16.
Minor polyhydroxysteroids from the starfishCrossaster papposus have been isolated and characterized: 5-cholestane-3,6,8,15,16,26-hexanol and 24-methyl-5-cholesta-14,22E-diene-3,6,8,26-tetraol 26-O-(3-O-methyl--D-glucopyranoside) (crossasteroside P3). The structures of the compounds were established on the basis of spectral methods.Pacific Ocean Institute of Bioorganic Chemistry, Far Eastern Branch, USSR Academy of Sciences, Vladivostok. Translated from Khimiya Prirodnykh Soedinenii, No. 2, p. 218–221, March–April, 1990.  相似文献   

17.
Conclusions The reaction of diphenylchlorophosphine with ,,-trichloro--hydroxyethyl ethyl sulfide in the presence of triethylamine leads to the formation of -ethylthio-,,-trichloroethyl diphenylphosphonite. The reaction of diphenylchlorophosphine with dimethyl -hydroxy--propylthiophosphonate in the presence of triethylamine gives -propylthio--dimethylphosphonoethyl diphenylphosphonite. The phosphorylated hemimercaptals obtained are thermally unstable and decompose to S-alkyl diphenylthiophosphonites and the corresponding carbonyl compounds.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 11, pp. 2619–2621, November, 1985.  相似文献   

18.
Summary The effect of the substitution in position 1 on the low-energy conformations of the oxytocin/vasopressin 20-membered ring was investigated by means of molecular mechanics. Three representative substitutions were considered: -mercapto-,-dimethyl)propionic acid (Dmp), (-mercapto-,-cyclopentamethylene)propionic acid (Cpp), both forming strong antagonists, and (,-dimethyl--mercapto)propionic acid (-Dmp), forming analogs of strongly reduced biological activity, with the -mercaptopropionic (Mpa) residue taken as reference. Both ECEPP/2 (rigid valence geometry) and AMBER (flexible valence geometry) force fields were employed in the calculations. Three basic types of backbone conformations were taken into account which are distinguished by the type of -turn at residues 3 and 4: 1/III, II, and I/III, all types containing one or two intra-annular hydrogen bonds. The allowed (ring-closed) disulfide-bridge conformations were searched by an algorithm formulated in terms of scanning the disulfide-bridge torsional angle C-S-S-C. The ECEPP/2 and AMBER energies of the obtained conformations were found to be in reasonable agreement. Two of the low-energy conformers of the [Mpa1]-compound agreed very well with the cyclic part of the two conformers found in the crystal structure of [Mpa1]-oxytocin. An analysis of the effect of -substitution on relative energies showed that the conformations with the N-C-CH2-CH2 (1) and C-CH2-CH2-S (1) angles of the first residue around (–100°, 60°) and (100°, –60°) are not affected; this in most cases implies a left-handed disulfide bridge. In the case of -substitution the allowed values of 1 are close to ± 60°. This requirement, being in contradiction to the one concerning -substitution, could explain the very low biological activity of the -substituted analogs. The conformational preferences of substituted compounds can largely be explained by the analysis of local interactions within the first residue. Based on the selection of the conformations which are low in energy for both the reference and -substituted compounds, two distinct types of possible binding conformations were proposed, the first one being similar to the crystal conformer with a left-handed disulfide bridge, the second one having a right-handed bridge, but a geometry different from that of the crystal conformer with the right-handed bridge. The first type of disulfide-bridge arrangement is equally favorable for both I/III and II types of backbone structure, while the second one is allowed only for the II type of backbone. No conformation of the I/III type has a low enough energy to be considered as a possible binding conformation for all of the active compounds studied in this work.  相似文献   

19.
The new cycloartane glycoside cyclounifolioside D (1) was isolated from roots of Astragalus unifoliolatus Bunge. The structure of 16-O-acetyl-24R-cycloartan-3,6,16,24,25-pentaol 3-O--D-glucopyranoside was established using chemical transformations and spectral data.  相似文献   

20.
In a continuation of investigations of proanthocyanidins of the roots ofRhodiola pamiroalaica, we have isolated proanthocyanidins RP-3 and RP-4. Their compositions, structures, and relative configurations have been investigated: RP-3 is 7-O-(6-O-galloyl--D-Glcp)-3-O-galloyl-(-)-epigallocatechin-(4-8)-[(-)-epicatechin-(4-8)-(3-O-galloyl-(-)-epigallocatechin)]2-(4-8)-[5-O-(-D-GlcpO--D-Glcp)-(+)-catechin], and RP-4 is 7-O-(6-O-galloyl--D-Glcp-3-O-galloyl-(-)-epigallocatechin-(4-8)-[3-O-galloyl-(-)-galloyl-5-(-D-GlcpO--D-Glcp)-(-)-epigallocatechinTranslated from Khimiya Prirodnykh Soedinenii, No. 1, pp. 42–49, January–February, 1999.  相似文献   

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