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1.
A number of -skatyl--substituted acetoacetic esters (ethyl, tert. -butyl, and benzyl) are prepared by treating gramine with sodium derivatives of -substituted acetoacetic esters. When ethyl -alkyl--skatylacetoacetates are heated with dilute alkali, they are split into indole and a substituted acetoacetic ester, while saponification with concentrated alcoholic alkali gives -substituted-(3-indolyl)propionic acids. 3-Skatyl-heptan-2-one can be obtained by pyrolysis of 3-skatyl-3-carbo-tert. -butoxyheptan-2-one, or by hydrogenolysis of 3-skatyl-3-carbobenzoxyheptan-2-one over a palladium catalyst. Alkylation of cycloheptanone and cyclohexanone enamines by gramine gives cyclic-(3-indolyl)ketones, viz., 2-skatylcyclopentanone and 2-skatylcyclohexanone.  相似文献   

2.
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   

3.
-Cyclodextrin having cinnamamide at 6- or 3-positions (6-CiNH--CD, 3-CiNH--CD) and -cyclodextrin with cinnamamide on 6-position (6-CiNH--CD) have been prepared. Supramolecular structures were formed in the solid state or aqueous solutions and characterized by measurements of NMR and vapor pressure osmometry (VPO). The results indicate that 6-CiNH--CD formed insoluble supramolecular polymers in the solid state, while 6-CiNH--CD and 3-CiNH--CD formed supramolecular complexes in aqueous solutions. 6-CiNH--CD was found to form a dimer in an aqueous solution. 3-CiNH--CD formed intermolecular complexes to give supramolecular polymers. The differences of the position of guest part on cyclodextrins caused to give a variety of supramolecular structures in aqueous solutions.  相似文献   

4.
The leaves of common ivy have yielded 11 triterpene glycosides: the 3-O--L-pyranosides of oleanolic acid (1), of echinocystic acid (2), and of hederagenin; the 3-O-[O--L-rhamnopyranosyl-(12)--L-arabinopyranoside]s of oleanolic acid (4), of echinocystic acid (5), and of hederagenin (6); the O--L-rhamnopyranosyl-(14)-O--D-glucopyranosyl-(16)-O--D-glucopyranosyl ester of hederagenin 3-O--L-pyranoside (7); the O--D-glucopyranosyl-(16)-O--D-glucopyranosyl ester of hederagenin 3-O-[O--L-pyranosyl-(12)--L-arabinopyranoside] (9); and the O--L-rhamnopyranosyl-(14)-O--D-glucopyranosyl-(16)-O--D-glucopyranosyl esters of oleanolic acid, echinocystic acid, and hederagenin 3-O-[O--L-rhamnopyranosyl-(12)--D-glucopyranoside]s (8), (10), and (11), respectively. This is the first time that compounds (1), (2), (5), (7), (9), and (10) have been found in this plant.Simferopol' State University. Translated from Khimiya Prirodnykh Soedinenii, No. 6, pp. 742–746, November–December, 1994.  相似文献   

5.
Monosubstituted - and -alkylthiophans and -, -, and -alkylthiacyclohexanes were subjected to a comparative mass spectrometric study. The stability of the M+ ion increases on passing from - to -alkylthiophans and from - to - and -alkylthiacyclohexanes. In the case of -alkylthiophans and - and -alkylthia-cyclohexanes the principal process is associated with ejection of the substituent as a whole, whereas a portion of the alkyl substituent, with retention of one CH2 group in the composition of the charged fragment, is eliminated from the molecular ions of -alkylthiophans and -alkylthiacyclohexanes.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 2, pp. 176–181, February, 1978.  相似文献   

6.
Five new sulfated derivatives of sokotrasterol and halistanol have been obtained: 24-nor-5-cholane-2,3,6,23-tetraol 2,3,6-tri(sodium sulfate); 24-nor-5-cholane-2,3,6,23-tetraol 2,3,6-tri(sodium sulfate) 23-palmitate; 24,25-dimethyl-5-cholestane-2,3,6-triol 3-(sodium sulfate); 24,25-dimethyl-5-cholestane-2,3,6-triol 6-(sodium sulfate); and 24,25-dimethyl-5-cholestane-2,3,6-triol 2,6-di(sodium sulfate). The inhibiting and membranolytic properties of the polysulfated steroids from sponges and their derivatives have been studied. It has been shown that physiological activity in this series of compounds depends on biphilicity.Pacific Ocean Institute of Bioorganic Chemistry, Far Eastern Scientific Center, Academy of Sciences of the USSR, Vladivostok. Translated from Khimiya Prirodnykh Soedinenii, No. 4, pp. 441–445, July–August, 1986.  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.
    
Zusammenfassung Es wird eine neue Methode zur spezifischen Bestimmung von freiem -Naphthol in Gegenwart eines großen Überschusses von -Naphthylesteremulsion beschrieben. Alle notwendigen reaktionskinetischen und optischen Bedingungen werden untersucht. Die Methode eignet sich besonders gut zur enzymatischen Analyse von Fermenten, die -Naphthylester hydrolysieren. Nach genauer Beschreibung von Arbeitsvorschriften werden folgende Anwendungsbeispiele ausgeführt: a) die Bestimmung von freiem -Naphthol in rohen -Naphthylesterpräparaten, b) die Bestimmung von Enzymaktivitäten: Substratvariation im menschlichen Serum, c) Verwendung als Suchreaktion: Ortung der -Naphthylpropionat spaltenden Fermente und Proteine des menschlichen Serums durch biologische Analyse der Eluate nach präparativer Stärkebreielektrophorese. Die Empfindlichkeit der Methode beträgt mindestens 0,1 Mol -Naphthol; die Störanfälligkeit ist minimal.
Summary A new method is described for the specific determination of free -naphthol in presence of a large excess of emulsions of -naphthol esters. The kinetics of the reaction and all optical conditions are tested. The method is applicable to the determination of esterases which hydrolyse -naphthol esters. The following examples for the use of the method are described: a) determination of free -naphthol in industrial -naphthol ester preparations, b) determination of esterase activities; c) application as finding test: localisation of the -naphthol propionic acid ester hydrolysing esterases and proteins of human serum by biological analysis of the eluates after preparative starch electrophoresis. The sensitivity is at least 0.1 Mol of -naphthol; the security is optimal.


Meinem verehrten Lehrer Herrn Univ. Prof. Dr. Alois Musil zum 65. Geburtstag gewidmet.  相似文献   

9.
The pseudoguaianolide inuchinenolide C and the eudesmanolide pulchellin C have been isolated for the first time from the flower heads and leaves ofInula caspica Blume, and their spatial structures have been established by an x-ray structural experiment as 2,6-diacetoxy-6-hydroxy-1,7(H),8,10(H)-pseudoguai-11(13)-en-8,12-olide and 2,3-dihydroxy-5,7,8(H)-eudesma-4(15),11(13)-dien-8,12-olide, respectively.Institute of Organic Synthesis and Coal Chemistry, Academy of Sciences of the Kazakh SSR, Karaganda. A. N. Nesmeyanov Institute of Organometallic Compounds, Academy of Sciences of the USSR, Moscow. Translated from Khimiya Prirodnykh Soedinenii, No. 6, pp. 748–757, November–December, 1990.  相似文献   

10.
Summary The condensation of trifluoroethylene with paraformaldehyde in the presence of sulfuric and chlorosulfonic acids has been carried out. -Fluorohydracrylic, -fluoro--chloropropionic, and -fluoro--bromopropionic acids have been obtained.  相似文献   

11.
Efficient synthesis of cyclic -alkyl--dicarbonyl compounds of the cyclopentane, cyclohexane, tetronic acid, and -pyrone series from the corresponding cyclic -acyl--dicarbonyl compounds under the action of NaBH3(CN) in a THF--HCl system is described.  相似文献   

12.
Conclusions The structure of two triterpone glycosides fromSapindus mukorossi Gaertn. has been established. It has been shown that sapindoside A is hederagenin 3-O--L-arabinosyl-(2 1)--L-rhamnopyranoside and sapindoside B is the 3-O--L-arabopyranosyl-(2 1)-O--L-rhamnopyranosyl-(3 1)--D-xylopyranoside.  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.
The epithermal neutron spectrum shape parameter in nuclear reactors is explained from a theoretical point of view in terms of the neutron slowing down density function. The latter is approximated by Fermi's age theory. Values for are calculated for a simple approximation of a nuclear reactor: a disk shaped fission neutron source in an infinite graphite moderator. The model produces -values with the correct sign and magnitude, compared to experimental values from the literature, determined in a real reactor. It is shown that varies strongly with distance to the neutron source and less strongly with neutron energy. The inappropriateness of average -values, obtained from the slope of quasi-straight lines produced by log-log plots of E versus E, for the correction of non-ideal epithermal neutron activation is discussed. Conclusions are formulated concerning the impact of an energy dependent on comparator type NAA.  相似文献   

15.
Stereoisomers of 1,5,6,7(H)- and 1,5,6,7(H)-guai-11(13)-en-6,12-olides are calculated using molecular mechanics. The possibility of forming various conformations in the 7-membered ring is examined as a function of the fusion to the 5-membered C-ring. The effect of the methyl orientation on the conformation of the 7-membered ring and the relative stability of the conformers are discussed.Insitute of Phytochemistry, Karaganda, fax (3212)-43-37-73. Translated from Khimiya Prirodnykh Soedinenii, No. 1, pp. 54–56, January–February, 2000.  相似文献   

16.
The syntheses of the 2-anilinocyclopentanones2 a–2 e in yields about 50% by reaction of 2-chlorocyclopentanone with 4-chloroaniline, N-methyl-4-chloroaniline, ,,-trifluoro-3-toluidine, N-methyl-,,-trifluoro-3-toluidine and 3,4,5-trimethoxyaniline, are described.  相似文献   

17.
A model of a truncated harmonic oscillator with equidistant levels and one-quantum transitions is applied. The balance equations for O2 have been solved numerically with 26 levels, with the transition probabilities taken as P k,k +1k exp (k) P 10, in which k is the number of the level and is an adjustable parameter that takes account of the anharmonicity. A Boltzmann distribution is obtained up to level 19 with =0, but for 0 there are deviations from that distribution in lower levels. Levels with k=1, 2, 3 are populated with relaxation times substantially less than the relaxation time for the vibrational energy. Dissociation depletes levels with k 19.  相似文献   

18.
Experimental results on the electrophoretic velocity and mobility of Ca-montmorillonite in 2-propanol are reported. The variation of the electrophoretic velocity with the externally applied electric field and the particle size range, at constant volume fraction and temperature, is considered. Given the difficulties for determining the types and concentrations of ions present in these liquid media, two methods are discussed for the estimation of the double layer thickness and hence the product, necessary for the determination of the zeta potential () of the interface. Although both methods of calculation yield different values of, the results for the zeta potential are very similar in the regions of and characteristic of our systems. The application to the experimental data of three theoretical relations between electrophoretic mobility and zeta potential is also discussed.  相似文献   

19.
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   

20.
Solasodine (I) has been subjected to a number of transformations. The following compounds have been obtained from it by described procedures: 3-acetoxypregna-5,16-dien-20-one (II), 3-acetoxypregn-5-en-20-ol (III), and 3-acetoxypregn-5-en-20-ol (IV). The oxidation of (III) and (IV), the formation of an oxime, and the reduction of the oxime with sodium in ethanol, followed by Hess methylation, has led to 20-dimethylaminopregn-5-en-3-ol (IX) and to 20-dimethylaminopregn-5-en-3-ol (X). From compounds (IX) and (X), by analogy with (III) and (IV) by their oxidation and the preparation of oximes, which were then reduced and methylated, the following were obtained: 3,20-bisdimethylaminopregnane (XVII) and 3,20-bisdimethylaminopregnane (XVIII), and also quaternary salts of the latter.Institute of the Chemistry of Plant Substances, Academy of Sciences of the Uzbek SSR, Tashkent. Translated from Khimiya Prirodnykh Soedinenii, No. 3, pp. 370–374, May–June, 1980.  相似文献   

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