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1.
Zusammenfassung Analog wie in vorherigen Mitteilungen1–4 wurden -Pyridyl-hydrazono-cyanacetylcarbamidsäureäthylester (1), 1-(-Pyridyl)-5-cyan-6-azauracil (2), 1-(-Pyridyl)-6-azauracil-5-carbonsäure (3), deren Thioamid (4), und Amidoxim (5), welches in 1-(-Pyridyl)-5-[5-methyl-1,2,4-oxdiazolyl(3)]-6-azauracil (6) überge-führt wurde, hergestellt.
-Pyridylhydrazono-cyanacetylcarbamic acid ethyl ester (1), l-(-pyridyl)-5-cyano-6-azauracil (2), 1-(-pyridyl)-6-azauracil-5-carboxylic acid (3), its thioamide (4) and amidoxime (5) were prepared as described in preceding communications. (5) was converted into l-(-pyridyl)-5-[5-methyl-1,2,4-oxdiazolyl(3)]-6-azauracil (6).
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2.
Zusammenfassung Die polarographische Methode des Indikatorions wurde zur Untersuchung der Komplexbildung des Mg2+-Ions mit Ammoniak verwendet. Es wurden die Stabilitätskonstanten 1,2,3,4 und ein annähernder Wert für 5 bestimmt.
Investigation of stability constants of magnesium ion-ammonia complexes
The polarographic method with indicator ion was used for investigation of magnesium ion complexation with ammonia. The numerical values of the stability constants 1,2,3,4 and the approximative value of 5 were determined.


Mit 2 Abbildungen  相似文献   

3.
Two new glycosides, gomphotin (1) and gomphotoxin (13), and also the known gomphoside (9) have been isolated from the leaves ofGomophocarpus fruticosus. Compounds (1) and (9) contain a 4,6-dideoxyhexosulose residue as the sugar component, and (13) a 6-deoxyhexosulose, which are attached to glycolic OH groups of the aglycons by 3-O-1,2-O-2 (9, 13) and 3-O-1,4-O-2 (1) acetal-ketal bonds. The structures of the new compounds are represented by the names (3-O-1,4-O-2)-(2,3-dihydroxy-4, 6dideoxyhexulosido)-14-hydroxy-5-card-20(22)-enolide* (1) and (3-O-1,2-O-2)-(2,3,4-trihydroxy-6-deoxyhexulosido)-14-hydroxy-5-card-20(22)-enolide* (13).State Scientific Center for Drugs of the Ministry of Health and the National Academy of Sciences of the Ukraine, Kharkov, fax 441118. Translated from Khimiya Prirodnykh Soedinenii, No. 6, pp. 824–832, November–December, 1995. Original article submitted May 22, 1995.  相似文献   

4.
Summary Ring opening of -trifluoromethyl- -methyl- -propiolactone is unidirectional and leads to derivatives of -trifluoromethyl- -hydroxybutyric acid.  相似文献   

5.
Summary The effect of tri-O-methyl--cyclodextrin(methyl--CD) on the partition coefficients of drugs, such as p-nitrophenol, salicylic acid, benzoic acid, and aspirin, was studied at 25°C. The partition coefficients of these drugs were increased linearly with methyl--CD concentration. The increase of partition coefficients was interpreted by the 11 complex formation between methyl--CD and the drug in CHCl3 phase.The interaction between p-nitrophenol and methyl--CD in solution was studied by UV and PMR spectroscopies. It was concluded that p-nitrophenol is included in the cavity of methyl--CD in both aqueous solution and CHCl3 solution.Inclusion compounds of these drugs with methyl--CD in the solid state were studied by X-ray diffractometry, IR spectroscopy, and DSC measurements. 11 crystalline inclusion compounds were obtained from hot water. It is also suggested that amorphous inclusion compound was obtained by the grinding of drug with methyl--CD.The dissolution rate and the bioavailability of ketoprofen were significantly increased in the presence of methyl--CD. The bioavailability of ketoprofen after oral administration with methyl--CD to rats was 3.7 times that of ketoprofen alone.  相似文献   

6.
One new and four previously known steroid compounds were identified from the Pacific starfishesLuidia quinaria andDistolasterias elegans. The structure of the new steroid was established from spectral data and chemical correlations with other steroids such as 5-cholestane-3,5,6,15,16,26-hexaol 3-sulfate (1). The previously known compounds were identified as 5-cholestane-3,5,6,15,26-pentaol 15-sulfate (2) fromLuidia quinaria and sodium (24S)-O-(-d-giucopyranosyll-5-cholestane-3,6,8,15,24-pentaol 6-sulfate (3), sodium (24S)-5-cholestane-3,6,8,15,24-pentaol 24-sulfate (4), and sodium tornasterol A sulfate (5).Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 2, pp. 473–476, February, 1996.  相似文献   

7.
Literature information is given on the current state of the study of the chemical transformation of cycloartane triterpenoids. A method has been developed for the transformation of the genin part of glycosides of 20,24-epoxycycloartan-25-ols with retention of the carbohydrate constituents. Three 25-norglycosides have been synthesized from natural cyclosieversigenin glycosides, namely 16-acetoxy-3,6-dihydroxy-20R,25-norcycloartan-20,24-olide 3-O-[O--L-arabinopyranosyl-(12)--D-xylopyranoside] 6-O--D-xylopyranoside (VIII), sodium 3,6,16,20-tetrahydroxy-20R,25-norcycloartan-24-oate 6-O--D-glucopyranoside 3-O--D-xylopyranoside (XII), and 20R,25-norcycloartane-3,6,16,20,24-pentaol 6-O--D-glucopyranoside 3-O--D-xylopyranoside (XIII).Institute of the Chemistry of Plant Substances, Academy of Sciences of the Republic of Uzbekistan, Tashkent. Translated from Khimiya Prirodnykh Soedinenii, No. 5, pp. 710–718, September–October, 1993.  相似文献   

8.
Zusammenfassung Ausgehend vom Brom-dimethylacetal wird über dendl--Diphenylmethylenaminoxy--aminopropionsäureester (III) der bekanntedl--Aminoxy--aminopropionsäureester (II) gewonnen. In neu bearbeiteter Cyclisierungsreaktion wurdedl-Cycloserin (I) erhalten, dessen Stabilität in Abhängigkeit vom Medium studiert wurde. Der aus (III) durch optische Spaltung zugängliche (–)-drehende Antipode wurde in ähnlichem Synthesegang in natürlichesd-Cycloserin (I) übergeführt.  相似文献   

9.
Zusammenfassung Die frühere Annahme, daß die beiden Modifikationen von-Naphthol den gleichen Schmelzpunkt besitzen und somit einen Grenzfall der Enantiotropie darstellen, wurde durch differentialthermoanalytische Untersuchungen widerlegt. Die beiden Modifikationen stehen zueinander im Verhältnis der Monotropie mit der allerdings nur geringen Schmelzpunktsdifferenz von 0,5°. Auch die IR-Spektren der beiden Kristallformen bestätigen das Vorliegen einer Monotropie.Für die Phasendiagramme der Naphthalingruppe, an denen-Naphthol beteiligt ist, ergeben sich Korrekturen. Da die instabile Mod. II die mit Naphthalin korrespondierende Kristallform ist, liegt in dem System Naphthalin--Naphthol keine lückenlose Mischkristallreihe vor (Typ. I, Roozeboom), sondern es wird eine Mischungslücke gebildet, denn das System besteht aus zwei Mischkristallphasen (Typ. IV). Auch im System-Naphthol--Naphthylamin tritt auf der-Naphtholseite eine bisher nicht erkannte Phasenüberschneidung auf und anstelle von Typ. III wird Typ. V (Roozeboom) gebildet.Schmelzdiagramme ohne Mischkristallbildung-Naphthol--Naphthol,-Naphthol--Naphthylamin) sind von einer Korrektur nur insofern betroffen, als die Kurvenäste der beiden Modifikationen des-Naphthols nicht von einem Punkt ausgehen und der stabile Kurvenast nicht als Mod. II, sondern als Mod. I bezeichnet werden muß.
New results on the polymorphism of-naphthol and its effects on the phase diagrams of the naphthalene group
Summary The earlier assumption that the two modifications of-naphthol have the same melting point and thus constitute a borderline case of enantiotropy was disproved by differential thermoanalytic investigations. The two modifications only have the slight difference in melting point of 0.5°. The IR spectra of the two crystal forms confirm the presence of monotropy.There are corrections for the phase diagrams of the naphthalene group in which-naphthol is involved. Since the unstable modification III is the crystal form corresponding to naphthalene, there is no unbroken series of mixed crystals in the naphthalene--naphthol system (Type I, Roozeboom), but a mixing gap is formed since the system consists of two mixed crystal phases (Type IV). A phase overlap which had not been previously recognized also occurs on the side of-naphthol in the-naphthol--naphthylamine system; the Roozeboom Type V is formed instead of Type III. The melting diagrams of a mixed crystal formation (-naphthol--naphthol,-naphthol--naphthylamine) are affected by a correction only to the extent that the curve branches of the two modifications of-naphthol do not begin at one point and the stable branch of the curve must be designated not as modification II but as modification I.
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10.
Fluoride and sulphate complexing of Np(VI) has been studied by controlled-potential coulometry at a constant ionic strength. The values of 1 * and 2 * for fluoride complexes were found to be 9.4 and 8.9, respectively, at an ionic strength =0.5. At an ionic strength =1.0, 1 * and 2 * obtained were 6.6 and 10.5, respectively. Sulphate complexing of Np(VI) was studied only at an ionic strength =0.5. The value of 1 * obtained was 5.6.  相似文献   

11.
Proofs are given of the structures of two new glycosides of the furostan series isolated from the leaves of the plantNolina microscarpa S. Wats. (family Dracaenaceae). Nolinofuroside D is (25S)-furost-5-ene-1,3,22,26-tetraol 1-O--D-galactopyranoside 26-O--D-glucopyranoside (I), and nolinofuroside F is (25S)-furost-5-ene-1,3,22,26-tetraol 1-O--D-fucopyranoside 26-O--D-glucopyranoside 3-O--L-rhamnopyranoside (VII). The latter was characterized as its 22-O-methyl ether (VIII). Nolinofuroside E (IV) has the structure of (25S)-furost-5-ene-1,3,22,26-tetraol 26-O--glucopyranoside 1-O-[O--L-rhamnopyranosyl-(12)--D-fucopyranoside], which followed from the structure of the fermentation product (VI). The products of the fermentation of the above-named compounds were present in the plant in only trace amounts. Only one of them — nolinospiroside D (III) — has not been described previously. This monoside of the spirostan series is (25S)-spirost-5-ene-1,3-diol 1-O--D-galactopyranoside.M. V. Frunze Simferopol' State University. Institute of Chemistry of Plant Substances, Uzbek Academy of Sciences, Tashkent. Translated from Khimiya Prirodnykh Soedinenii, No. 5, pp. 678–686, September–October, 1991.  相似文献   

12.
Catalytic activity of homogeneous and heterogeneous rhodium complexes with polyethyleneimine or ethylenediamine at various Rh:N ratios has been studied in the reaction of water reduction to dihydrogen by V aq 2+ and Cr aq 2+ and the applicability of these catalysts for photocatalytic evolution of H2 from water is discussed.
Rh:N V ap 2+ Cr aq 2+ .
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13.
In addition to the know steroid sapogenin (25S)-ruscogenin (I), three new glycosides have been isolated from the leaves ofNolina microcarpa S. Wats. (family Dracaenacea), and the following structures are suggested for them: (25S)-spirost-5-ene-1,3-diol 1-O--D-fucopyranoside (nolinospiroside C, II), (25S)-furost-5-ene-1,3,22,26-tetraol 1-O--D-fucopyranoside (nolinofuroside A, III), and (25S)-furost-5-ene-1, 3, 22, 26-tetraol 1-O--D-fucopyranoside 26-O--D-glucopyranoside (nolinofuroside C, V).M. V. Frunze Simferopol' State University. Institute of Chemistry of Plant Substances, Uzbek Academy of Sciences, Tashkent. Translated from Khimiya Prirodnykh Soedinenii, No. 5, pp. 672–678, September–October, 1991.  相似文献   

14.
Zusammenfassung Das Nebenprodukt, welches bei der Bildung der Bi-pyridonyle3 aus dimerem Malonitril (2) und Arylaminopropenonen (1) anfällt, wird als Tetrahydro-1,8-naphthyridinderivat4 b erkannt und seine Eigenschaften beschrieben. Da für die Entstehung von4 b das intermediäre Auftreten von Phenyl-vinylketon angenommen werden kann, wird das Verhalten des letzteren gegenüber Nitrilen im Sinne einerRitter-Reaktion untersucht. Mit Benzonitril kann das -Benzamido-propiophenon8 erhalten werden. Auch -Dimethylamino-propiophenon eignet sich zu Kondensationen mit dimerem Malonitril und Glutazinderivaten. Durch Dehydrierung werden dabei dieselben Produkte isoliert wie bei der Verwendung von Enaminoketonen. Der Mechanismus dieser Reaktionen wird diskutiert.
Syntheses with nitriles, XXVIII.: Contributions to the ritter reaction
The by-product of the synthesis of the bi-pyridonyls3, from dimeric malononitrile and aryl-aminopropenones (1) is the tetrahydro-1,8-naphthyridine derivative4 b. Since phenyl vinyl ketone is an intermediate for the formation of4 b its reaction with nitriles is investigated.Ritter reaction with benzonitrile leads to -benzamido-propiophenone (8). -Dimethylaminopropiophenone is used for condensations with dimeric malononitrile or glutazine derivatives, too. The reaction proceeds with dehydrogenation to give the same products as obtained with enamino ketones. The mechanism is discussed.
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15.
Three new glycosides, D1, D2, and D3, have been isolated from the Far Eastern starfishDistolasterias nipon. They have been identified by chemical and physicochemical methods as 5-cholestane÷3,6,8,15,24-pentaol 3,24-di-O--D-xylopyranoside, t-cholest-22-ene-3,6,8,15,24-pentaol 3,24-di-O--D-xylopyranoside (II), and 5-cholestane-3,6,8,15,24-pentaol 24-O--D-glucopyranoside 3-O--D-xylopyranoside (III).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. 250–255, March–April, 1987.  相似文献   

16.
Summary The dichloride of -ethoxyvinyl-, -isooctyloxyvinyl-, and 2-chloro-3-methylbut-3-enylphosphonous acids have been synthesized and characterized for the first time. The diethyl ester of -ethoxyvinylphosphonous acid has been-obtained from the dichloride of -ethoxyvinylphosphonous acid.  相似文献   

17.
Crystallization of organometallic dipyridine(1,1'-bis(ethenyl-2-pyridyl)-ferrocene) (1) with(±)-1,1'-bi-2-naphthol (2) from EtOH,i-PrOH, (±)-2-BuOH, and MeOH forms crystallineinclusion compounds of stoichiometries1 2 C2H5OH (3, 1 2 C3H7OH (4),1 2 C4H9OH (5),and 1 2 CH3OHH2O(6), respectively. Thecrystalline species 3, 4, and 5 areisostructural with the three molecular componentsinterlinked by hydrogen bonds to form a columnarstructure. In 6, the four molecular componentsare interlinked by hydrogen bonds to form atwo-dimensional framework structure.  相似文献   

18.
Zusammenfassung Die Protonenresonanzspektren von -1-Brom-2,4,6-triacetyl-3-[(benzylthio)carbonyl]-d-galaktopyranose, 3-[(Benzylthio)carbonyl]-4,6-benzyliden--methyl-d-galaktopyranosid, 3-[(Benzylthio)carbonyl]--methyl-d-galaktopyranosid, 3-[(Benzylthio)carbonyl]--d-galaktopyranose, 1,2,4,6-Tetraacetyl-3-[(benzylthio)-carbonyl]--d-galaktopyranose, 2,4,6-Triacetyl-3-[(benzylthio)-carbonyl]--methyl-d-galaktopyranosid und von 2,4,6-Triacetyl--d-galaktopyranosid werden diskutiert. Sie stehen völlig in Einklang mit der C-1-Konformation der untersuchten Verbindungen.Mit 3 AbbildungenHerrn Prof. Dr.J. W. Breitenbach zum 60. Geburtstag gewidmet.  相似文献   

19.
Conclusions The 3-0- and 4-0-trityl ethers of the acetates of methyl -L- arid methyl -L-arabinopyranosides were synthesized. The glycosylation of the ethers with the aid of 3,4-di-0-acetyl-1,2-0-(1-exo-cyano)ethylidene--L-arabinopyranose and the subsequent deacetylation of the synthesized products yielded the disaccharides: methyl 4-0-(-L-arabinopyranosyl)-,methyl 4-0-(-L-arabinopyranosyl)-, and methyl 3-0-(-L-arabinopyranosyl)--L-arabinopyranoside; and methyl 4-0-(-L-arabinopyranosyl)-, methyl 4-0-(-L-arabinopyranosyl)-, methyl 3-0-(-L-arabinopyranosyl)-, and methyl 3-0-(-L-arabinopyranosyl)--L-arabinopyranoside.The assignment of the signals in the PMR and13C NMR spectra of the synthesized arabinopyranosyl biosides was carried out, allowing the determination of the type and configuration of the glycosidic bond by means of which the arabinopyranose residues are linked in the oligo- and polysaccharide chains.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 1, pp. 200–209, January, 1986.  相似文献   

20.
Gromova  A. S.  Lutsky  V. I.  Cannon  J. G.  Li  D.  Owen  N. L. 《Russian Chemical Bulletin》2001,50(6):1107-1112
The chemical composition of the above-ground parts of Astragalus danicus and A. inopinatus collected in the Baikal region (Eastern Siberia) was studied for the first time. From A. danicus, pentacyclic triterpene saponins were isolated and identified, viz., 3-O-(-glucuronopyranosyl)-3,22,24-trihydroxyolean-12-ene, 3-O-[O-(-d-xylopyranosyl)-(12)-(-glucuronopyranosyl)]-3,22,24-trihydroxyolean-12-ene, 3-O-[O-(-d-glucopyranosyl)-(12)-(-glucuronopyranosyl)]-3,22,24-trihydroxyolean-12-ene, 3-O-[O-(-l-rhamnopyranosyl)-(12)-O-(-d-xylopyranosyl)-(12)-(-glucuronopyranosyl)]-3,22,24-trihydroxyolean-12-ene, 3-O-[O-(-l-rhamnopyranosyl)-(12)-O-(-d-glucopyranosyl)-(12)-(-glucuronopyranosyl)]-3,22,24-trihydroxyolean-12-ene, 3-O-methyl-d-chiro-inositol, and linolenic acid. In A. inopinatus, the same saponins were identified as well as tricosan-1-ol and tetracosan-1-ol, 5,7,4"-trihydroxyflavon (apigenin), and a tetracyclic triterpenoid, 20(R),24(S)-epoxycyclolanost-9(11)-ene-3,6,16,25-tetrol (cycloastragenol). All reported compounds from the both genus of Astragalus were isolated for the first time. Methanolic extracts of A. danicusand A. inopinatus exhibited low inhibitory activity with respect to the growth of HeLa cells. The chloroform fraction of A. danicus showed a strong antimicrobial activity against Staphylococcus aureus and a strong cytotoxic activity against HeLa cells.  相似文献   

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