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1.
Four new polyhydroxysteroids, 5-cholesta-3,5,6,15,16,25,26-heptaol, 24-ethyl-5-cholesta-3,5,6,15,28,29-heptaol-29-sulfate, (22E)-24-methyl-5-cholest-22-ene-3,5,6,15,25,26-hexaol-26-sulfate, 24-propyl-5-cholesta-3,5,6,8,15,28,29-heptaol, and the known 5-cholesta-3,5,6,15,16,26-hexaol, have been isolated from the starfishCtenodiscus crispatus.Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 10, pp. 1821–1825, October, 1994.  相似文献   

2.
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   

3.
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   

4.
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   

5.
Zusammenfassung Bei der Einwirkung von Schwefel und Ammoniak auf Propiophenon,n-Butyrophenon undi-Butyrophenon entstehen die entsprechenden Thiazoline-(3), deren saure Hydrolyse zu -Mercaptopropiophenon, -Mercapto-n-butyrophenon bzw. -Mercapto-i-butyrophenon führt. Die Dehydrierung dieser -Mercaptoketone mit Schwefel zu Di- bzw. Trisulfiden wird beschrieben. Die Kondensation der -Mercaptoketone mit Ammoniak und einer Oxokomponente führt zu neuen Thiazolinen-(3), von denen die in 2- und 5-Stellung monosubstituierten Vertreter sich mittels Schwefel zu Thiazolen dehydrieren lassen.
The interaction of sulfur and ammonia with propiophenone,n-butyrophenone andi-butyrophenone leads to the corresponding thiazolines-(3). On acid hydrolysis of the latter -mercaptopropiophenone, -mercapto-n-butyrophenone and -mercapto-i-butyrophenone respectively are formed. The dehydrogenation of these -mercaptoketones with sulfur to di- and trisulfides respectively is described. The condensation of the -mercaptoketones with ammonia and oxo-components yields new thiazolines-(3) of which the 2- and 5-monosubstituted compounds can be dehydrogenated to thiazols with elementary sulfur.
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6.
A new method was developed for the synthesis of -alkyl- and ,-dialkyl--phenyltryptamines based on alkylation of nitroalkanes with -phenyl-nor-gramine.  相似文献   

7.
N1-(-Tetrahydrofuranyl)- and N1-(-tetrahydropyranyl)uracils and the corresponding 6-azauracils have been obtained by the condensation of bistrimethylsilyl derivatives of uracils and 6-azauracils with-chlorotetrahydrofuran and-chlorotetrahydropyran. The superiority of the silyl method over the mercury method used previously has been demonstrated.For part III, see [9].  相似文献   

8.
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   

9.
Six polyhydroxylated steroids and their derivatives were isolated from the starfish Lysastrosoma anthosticta collected in the Posyet Bay, Sea of Japan. These include a new glycoside of the steroid polyol, lysastroside A (1), which was identified as (25S)-26-O--d-xylopyranosyl-5-cholestane-3,6,8,15,16,26-hexaol, and the previously known pycnopodioside C monoglycoside (2), marthasterone sulfate (3), (25S)-5-cholestane-3,6,8,15,16,26-hexaol (4), (25S)-5-cholestane-3,6,7,8,15,16,26-heptaol (5), and (25S)-5-cholestane-3,6,7,8,15,16,26-heptaol (6). The compounds were tested for the haemolytic activity and the action on the embryogenesis of the sea urchin Strongylocentrotus intermedius.  相似文献   

10.
    
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   

11.
Summary The identification of small amounts of sugars by their X-ray powder diagrams is suggested as a most simple and practical method in routine analysis.It is especially valuable in working with minute amounts of material, and has proved very useful for the final identification of chromatographically-separated sugars.The characteristics of the powder diagrams of a number of monosaccharides of special interest to the physiological chemist are reported in detail. The substances thus investigated are- and-D-glucose and-glucose monohydrate,- and-D-galactose,- and-D-mannose,D-fructose,D-glucuronolactone,- and-D-glucosamine hydrochloride,- and-D-galactosamine (chondrosamine) hydrochloride,-L-fucose, andD-ribose. For various reasons arabinose, lyxose, and xylose have also been included.It is clear from the powder diagrams of the galactoses that the crystalstructure earlier ascribed to-galactose is that of-galactose.A single-crystal study of-glucosamine hydrochloride was carried out by theWeissenberg technique. The crystal-dimensions obtained agree with those earlier found byCox et al5, 7.The optical rotation of chondrosamine hydrochloride was found to be [] D 20° = - 135° - 93° - 39°, the first value being considerably higher than that given for the-form byLevene. A method for the preparation of-mannose is described.
Zusammenfassung Die Identifizierung kleiner Mengen verschiedener Zuckerarten mit Hilfe ihrer Röntgen-Pulverdiagramme wird als einfache und praktische Routinemethode vorgeschlagen.Diese Methode ist besonders wertvoll, wenn nur kleine Substanzmengen zur Verfügung stehen, und hat sich für die endgültige Identifizierung von chromatographisch getrennten Zuckern als sehr geeignet erwiesen.Die Einzelheiten der Pulverdiagramme folgender physiologisch-chemisch bedeutungsvoller Monosaccharide werden mitgeteilt:- und-D-Glukose und Glukosehydrat,- und-D-Galaktose,- und-D-Mannose,D-Fruktose,D-Glukuronolakton,- und-D-Glukosaminhydrochlorid,- und-D-Galaktosamin-(Chondrosamin)-hydrochlorid,-L-Fukose, dieD-Pentosen Arabinose, Lyxose, Ribose und Xylose.Aus den Pulverdiagrammen der Galaktosen geht deutlich hervor, daß die Krystallstruktur, die früher der-Galaktose zugeschrieben wurde, tatsächlich diejenige der-Form ist.Die Untersuchung eines Einzelkristalles von-Glukosaminhydrochlorid wurde nach derWeissenberg-Technik ausgeführt. Die erhaltenen Werte stimmen mit den früher vonCox und Mitarbeitern gefundenen überein.Die optische Drehung des Chondrosaminhydrochlorids wurde zu [] D 20° = + 135° + 93° + 39° gefunden. Der erstgenannte Wert ist größer als der entsprechende, vonLevene angegebene Drehungswert.Eine Methode zur Darstellung von-Mannose wird beschrieben.

Résumé On propose une méthode de routine simple et pratique pour l'identification de petites quantités de divers sucres au moyen de leur diagramme de poudres aux rayons X. Cette méthode est particulièrement précieuse quand on n'a que de petites quantités de matière à sa disposition et elle s'est montrée très convenable pour l'identification finale de sucres séparés par chromatographie. Des particularités des diagrammes de poudres des monosaccharides suivants intéressent le chimiste physiologiste: et-D-glucose et hydrate de glucose, et-D-galactose, et-D-mannose, D-fructose,D-glucuronolactone, chlorhydrate d' et-D-glucosamine, chlorhydrate d' et-D-galactosamine (chondrosamine), l'-L-fucose, lesD-pentoses, l'arabinose, le lyxose, le ribose, le xylose. Des diagrammes de poudres des galactoses découle clairement le fait que la structure cristalline qui fut attribuée précédemment à l'-galactose est celle de la forme. L'expérience sur un cristal unique de chlorhydrate d'-glucosamine a été effectuée d'après la technique deWeissenberg. Les valeurs obtenues concordent avec celles trouvées précédemment parCox et ses collaborateurs. Le pouvoir rotatoire du chlorhydrate de chondrosamine a été trouvé égal à D 20 = + 135° + 93° + 39°. La première valeur est plus grande que celle donnée parLevene. On décrit une préparation de l'-mannose.


With 3 figures.  相似文献   

12.
A new method for determining the degree of conversion of gelation (gel) and gel time (t gel) at gel point using a single technology, DSC, is discussed in this work. Four kinds of thermoset resins are evaluated. It is found that the mutation points of reduced reaction rate (V r ) vs. reaction conversion () curves, corresponding with the changes of reaction mechanism, represents the gelation of the reaction. The at the mutation point is defined as gel. From isothermal DSC curves, the point at gel is defined ast gel. Traditional techniques (ASTM D3532 and DSC method) are also used to determine gel andt gel in order to demonstrate this new method. We have found that the results obtained from this new method are very consistent with the results obtained from traditional methods.  相似文献   

13.
The direction taken by the reaction of -hydroxylaminooximes (prepared by the action of hydroxylamine on -halogenoketones) with aldehydes depends on the geometric configuration of the oxime group, cis isomers reacting with benzaldehyde to give N -substituted -phenylnitrones and with acetaldehyde to give derivatives of 4H-1, 2, 5-oxadiazine. Anti--hydroxylaminooxime and acetaldehyde give substituted 1 -hydroxy-3-imidazolin-3-oxide. The structures of the compounds synthesized check by analyses of their UV and IR spectra.For Part VI see [1].  相似文献   

14.
One- and two-dimensional homo- and heteronuclear correlation proton, carbon, proton—proton, and proton—carbon NMR spectra of fifteen drimanic sesquiterpenoids: 11,12-dibromodrima-5,8-dien-7-one, drim-8-en-7-one, 11-hydroxydrim-8-en-7-one, 11,12-dihydroxydrim-8-en-7-one, 11-hydroxy-11,12-epoxydrim-8-en-7-one, 11-hydroxy-11,12-epoxydrim-8-en-7-one, 8,9-epoxydriman-7-one, 8,9-epoxydriman-7-ol, 11,12-diacetoxydrim-8-en-7-ol, drimane-7,8,11-triol, 7,8-isopropylidenedioxydriman-11-al, 9, 11-dihydroxydrim-7-en-6-one, drimane-7,8,9-triol, drimane-7,8,11-triol, and drim-8-ene-7,11,12-triol were studied. The proton and carbon chemical shifts were assigned.__________Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 12, pp. 2589–2594, December, 2004.  相似文献   

15.
From the seeds of tobacco Nicotiana tabacumL. we have isolated two new steroid glycosides, nicotianosidesC andF. The structures of the glycosides have been shown on the basis of chemical transformations and spectral characteristics. Nicotianoside C is a steroid glycoside of the spirostan series and has the structure of (25S)-5-spirostan-3ß-ol3-O-[-L-rhamnopyranosyl-(1 2)]-[-L-rhamnopyranosyl-(1 4)]-ß-Dglucopyranoside), and nicotianoside F is (25S)-5 furostan-3ß, 22, 26-triol 3-O-[-L-rhamnopyranosyl-(1 2)1-[-L-rhamnopyranosyl-(1 4)1-ß D-glucopyranoside) 26-O-ß-D-glucopyranoside.Institute of Genetics, Academy of Sciences of the Republic of Moldova, 277022, Kishinev, ul. Pédurilor, 20. Translated Khimiya Prirodnykh Soedinenii, No. 3, pp. 396–401, May–June, 1995. Original article submitted August 29, 1994.  相似文献   

16.
Conclusions The reaction of diethylamine, piperidine, ethylenimine, and cyclohexylamine with ethyl-fluoroacrylate, and also of ethylenimine with phenyl-fluorovinyl ketone, leads to the addition of the amines to the-fluorovinyl group with the formation of-fluoro--aminopropionic acid derivatives.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicneskaya, No. 10, pp. 2362–2363, October, 1975.  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.
Zusammenfassung Eine neue maßanalytische Methode zur Bestimmung von 16, 17-Dihydroxysteroiden wurde beschrieben. Die Titration wird mit Blei(IV)-acetat-Maßlösungen (0,01-n bzw. 0,001-n) in einer Lösung von Kaliumacetat in 0,25-n Essigsäure durchgeführt. Die Endpunktermittlung erfolgt potentiometrisch. Das Äquivalentverhältnis beträgt 12. Die beschriebene Methode ist zur Bestimmung von Zehntelprozenten 16,17-Dihydroxysteroid als Verunreinigung in deren Acetoniden geeignet.
Micro-titration of 16,17-Dihydroxy-steroids with standard lead tetraacetate solution
Summary A new volumetric method is described for the determination of 16,17-dihydroxy steroids. The titration is carried out using standard lead tetraacetate solution as the titrant (0.01N and 0.001N, resp.), while the solvent for the titration is the solution of potassium acetate in acetic acid (0.25N). The end point i s determined potentiometrically. The equivalent ratio is 1 2. The described method enables the determination of 0.1% of 16,17-dihydroxy steroid impurities in their acetonide derivatives.
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19.
Conclusions 16-Dehydropregnenolone acetate undergoes condensation with 1,2-dimethylenecyclobutane in the presence of a Lewis acid to form a 16,17-monoadduct, namely, 3,4-ethano-16,17-cyclohex-3-enopregn-5-en-3-ol-20-one acetate.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 10, pp. 2397–2399, October, 1985.  相似文献   

20.
    
Summary By the reaction of -hydroxymethylene- and -dimethylaminomethylene-2,3-polymethylene-3,4-dihydroquinazolin-4-ones with acid anhydrides and primary and secondary amines, the corresponding -acyloxymethylene- and -mono(di)-substituted aminomethylene-2,3-polymethylene-3,4-dihydroquinazolin-4-ones have been synthesized. The addition of hydrocyanic acid (from acetone cyanohydrin) to the double bond of the methylene group of the -hydroxymethylene- and -dimethylaminomethylene-2,3-trimethylene-3,4-dihydroquinazolin-4-ones has led to -[cyano-(hydroxy)methyl1]- and -[cyano(dimethylamino)methyl]-2,3-trimethylene-3,4-dihydroquinazolin-4-ones.Institute of the Chemistry of Plant Substances, Academy of Sciences of the Uzbek SSR, Tashkent. Translated from Khimiya Prirodnykh Soedinenii, No. 5, pp. 603–609, September–October, 1978.  相似文献   

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