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1.
Conclusions The reaction of 2,2-bis(4-hydroxy-3-N,N-diethylaminomethylphenyl)propane with triethyl phosphite gave 2,2-bis(4-ethoxy-3-diethylphosphonomethylphenyl)propane via the intermediate formation of a compound with a pentacovalent phosphorus atom. In the presence of acetic acid the reaction leads to 2,2-bis(4-hydroxy-3-diethylphosphonomethylphenyl)propane.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 7, pp. 1621–1624, July, 1978.  相似文献   

2.
1.4-Bis(4-hydroxy-1,2,5-trimethyl-4-piperidyl)-1.3-butadiyne has been synthesized from the individual isomers of 4-ethynyl-1,2,5-trimethyl-4-piperidol. Hydrogenation, bromination, and cleavage have given, respectively, 1,4-bis(4-hydroxy-1,2,5-trimethyl-4-piperidyl)butane, 1,4-bis(4-nydroxy-1,2,5-trimethyl-4-piperidyl)-1,2,3,4-tetrabromo-1, 3-butadiene, and 4-(1,3-butadiynyl)-1,2,5-trimethyl-4-piperidol.  相似文献   

3.
Conclusions From the roots ofSeseli sessiliflorum Schrenk a new chromone has been isolated for which the structure of 2,2-dimethyl-3-(3-methylthioacryloyloxy)-3,4-dihydropyrano-5,6:6,7-(5-hydroxy-2-methyl) chromone has been proposed. It is the first representative of this group of natural compounds containing sulfur.Khimiya Prirodnykh Soedinenii, Vol. 6, No. 4, pp. 412–415, 1970  相似文献   

4.
The methyl ester and N,N-diethylamide of 2-azido-5-phenyl-4-thiazolecarboxylic acid were obtained by the reaction of the corresponding 4-substituted 2-hydrazino-5-phenylthiazole with NaNO2 in acid media. IR and UV spectroscopy were used to show that the compounds synthesized retain azide form in both the crystalline state and in solution. The reaction of azides with dicarbonyl compounds gave derivatives of 2-[5-methyl-4-acetyl-or 2-[5-methyl-4-ethoxycarbonyl-1,2,3-triazol-1-yl]-5-phenylthiazole-4-carboxylic acid.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 5, pp. 710–714, May, 1993.  相似文献   

5.
Summary 1. In a study of the kinetics of the alkaline hydrolysis of flavone glycosides it has been found that derivatives of 3,3,4,5,7-pentahydroxyflavone hydrolyze faster than derivatives of 3,4,5,7-tetrahydroxyflavone and of 3,4,5,7-tetrahydroxy-3-methoxyflavone.2. In the hydrolysis of diglycosides of 3,3,4,5,7-pentahydroxyflavones the maximum amount of intermediate product is formed after 2 min (3,4,5,7-tetrahydroxyflavone glycoside), and in the case of 3,4,5,7-tetrahydroxy-3-methoxyflavone glycosides after 120–150 min.I. V. Kutateladze Institute of Pharmacochemistry, Academy of Sciences of the Georgian SSR, Tbilisi. Translated from Khimiya Prirodnykh Soedinenii, No. 5, pp. 646–649, September–October, 1977.  相似文献   

6.
Zusammenfassung Bei der Kondensation von o-Hydroxyacetophenon mit Malonsäure-dinitril in steigendem Molverhältnis entstehen vier Produkte: 3-Cyan-4-methyl-cumarin (II), 3-(1-Amino-2,2-dicyan)-äthen-4-methyl-cumarin (IV), 2H-Malonitril-3-(1-amino-2,2-dicyan)-äthen-4-methyl-benzopyran (V) sowie ein weiteres Anlagerungsprodukt mit vier Malonsäuredinitril-einheiten. 3-Cyanund 3-Acetyl-cumarine mit freier 4-Position addieren Malonsäuredinitril zum 3-Cyan- bzw. 3-Acetyl-4-[1,3,3-tricyan-2-amino-propen-(2)]-3,4-dihydro-cumarin (X und XI).Herrn Prof. Dr. et Mr.L. Zechner, Leiter der Galenischen Abteilung am Institut für Organische und Pharmazeutische Chemie der Universität Graz, zum 70. Geburtstag gewidmet.Vorgetragen beim Chemikertreffen Schweiz-Österreich, Innsbruck, Oktober 1963.  相似文献   

7.
Summary The influence of thymic factors on the levels of different cyclic nucleotides in human lymphoblastic lymphoma cells has been studied. A single-step HPLC method for the simultaneous determination of 2,3-cGMP, 3,5-cGMP, 2,3-cAMP and 3,5-cAMP from biological cell materials is described. Concentrations even in the picomolar range could be determined quantitatively.
Quantitative HPLC-Messung isomerer cyclischer Nucleotide aus T-Lymphocyten
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8.
A preparative synthesis of the antimetabolite 6-azacytidine is described which involves the amination under mild conditions without the use of an autoclave of 2, 3, 5-tri-O-acyl-4-thip-6-azauridines with the isolation of the intermediate 2, 3, 5-tri-O-acyl-6-azacytidines and subsequent elimination of the protective groups at room temperature.For communication VI, see [10].  相似文献   

9.
Zusammenfassung 4,4-Dihydroxydiphenyl-äthan (I) und 4,4-Dihydroxydiphenyl-propan (II) geben beim Kuppeln mit p-Nitrobenzoldiazoniumchlorid die o-Kernkupplungsprodukte (III, IV, V) und reagieren mit Chinonimidchlorid nicht. Dagegen werden 2,4,6-Trimethylphenol (Mesitol), 4,4-Dihydroxy-3,5,3,5-tetramethyldiphenyl-äthan (VI) und 4,4-Dihydroxy-3,5,3,5-tetramethyldiphenyl-propan (VII) von p-Nitrobenzoldiazoniumchlorid zu 4-Hydroxy-3,5-dimethyl-4-nitroazobenzol und von Chinonimidchlorid zum 4-Hydroxy-3,5-dimethylphenolindophenol (IX) zum Teil gespalten. Der Reaktionsmechanismus wird diskutiert.Als erste Mitteilung dieser Reiho gilt: Mh. Chem.93, 1 (1962).  相似文献   

10.
An x-ray structural study has shown that 6-(3-oxo-5,5-dimethyl-1-pyrrolin-3-yl)methylidene-2,2,7, 7-tetramethyl-4-hydroxybicyclo[2.2.2]azaoctane is formed as a low-molecular-weight byproduct of the solid-phase polymerization of 1,4-bis(2,2,6,6-tetramethyl-4-hydroxy-4-piperidyl)butadiyne.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 3, pp. 585–587, March, 1990.  相似文献   

11.
New tricylic heterocyclic systems and their methyl derivatives are synthesized. They are 2-methylimidazo[5, 4-e]benzo-1, 2, 3-thiadiazole, 2-methylimidazo[5, 4-g]benzo-1, 2', 3-thiadiazole, 1, 2-dimethylimidazo[5, 4-g]benzo-1, 2, 3-thiadiazole, and 1, 2-dimethylimidazo[5, 4-g]benzo-1, 2, 3-thiadiazole. Quaternary salts of the 1, 2-dimethyl derivatives are used to prepare symmetrical and unsymmetrical trimethinecyanines and dimethinemerocyanines containing rhodanine groups. The absorption maxima of the dyes are displaced towards the long wavelength region compared with imidacarbocyanines. It is shown that when 1, 2-dimetnyl-5-aminobenzoimidazole is thiocyanated, the thiocyano group enters the benzoimidazole ring at position 4, and that 1, 2-dimethylimidazo[5, 4-e] benzo-1, 2, 3-thiadiazole is less basic than its isomer 1, 2-dimethylimidazo[5, 4-g]benzo-1, 2, 3-thiadiazole.  相似文献   

12.
Zusammenfassung Die Synthese von geschützten 2,3-Dideoxy-2-hydroxymethyl-nucleosiden wird beschrieben. Die durch ein Mehrstufenverfahren aus Isopropylidenglycerol erhaltenen Nucleoside können als Bausteine zur Darstellung von Oligonucleotiden verwendet werden, deren 2- und 5-Positionen über eine Etherbrücke verbunden sind.
Synthesis of 2,3-dideoxy-2-hydroxymethyl nucleosides
Summary The synthesis of protected 2,3-dideoxy-2-hydroxymethyl nucleosides is presented. The nucleosides, obtained in a multi-step procedure starting from isopropylideneglycerol, may be used as building blocks for the synthesis of 2,5-ether linked oligonucleotides.
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13.
The action of N-methylpiperazine and , -dimethylpyrrolidine on chloroacetyl derivatives of phenylhydrazides of diaryl- and dialkylglycolic acids has given the previously unknown N-methylpiperazinoacetyl and , -dimethylpyrrolidnoacetyl derivatives of these phenylhydrazides.For part XL, see [1].  相似文献   

14.
From 2-amino-1-keto-1, 2, 3, 4-tetrahydronaphthalene, prepared by reduction of isonitroso--tetralone, a number of N-acyl derivatives are prepared, and these are converted further to 2-substituted 3, 4-dihydronaphth-1, 25, 4-oxazoles,  相似文献   

15.
The synthesis of 4,4-di(methylamino)- and 4,4-dianilino-3,3-diaminobiphenyls is described. The condensation of the tetraaminobiphenyls mentioned with phenyl perfluorobutyrate has given, respectively, 1,1-dlmethyl- and 1,1-diphenyl-2,2-(n-perfluoropropyl)-5, 5-bibenzimidazolyls. A study of the thermal stability of the 2-perfluoroalkylbenzimidazoles has shown that the replacement of the hydrogen of the imino group in these compounds by a methyl or a phenyl radical considerably increases their heat stability.  相似文献   

16.
Zusammenfassung Es wird über die Reaktion verschieden methylsubstituierter 4-Hydroxychalkone mittels Chinonimidchlorid berichtet und gezeigt, daß die Ausbeute an 2,6-Dimethylphenol-indophenol bei der Spaltung von 4,4-Dihydroxy-3,5,3-trimethylchalkon (VII) am RingB dreimal so groß ist als beim 4,4-Dihydroxy-3,3,5-trimethylchalkon (III) am RingA.
The reaction between several methyl-4-hydroxy-chalkones and p-benzoquinone-monochloroimine has been studied. It has been shown that the yield of 2.6-dimethylphenol-indophenol from the cleavage of 4.4-dihydroxy-3.5.3-trimethyl-chalkon (VII) at ringB is three times the yield resulting from the cleavage of 4.4-dihydroxy-3.3.5-trimethylchalkon (III) at ringA.


Herrn Prof. Dr.H. Bretschneider zum 60. Geburtstag gewidmet.  相似文献   

17.
Summary In an attempt to develop potential inhibitors ofUDP-glucuronosyltransferase, some 5-O-amino acid derivatives of uridine were synthesized. N-protectedL-amino acids were coupled at the 5-O-position of 2,3-O-isopropylideneuridine by esterification employing the method of symmetrical anhydrides in presence of 4-dimethylaminopyridine, 5-O-(N-benzyloxycarbonyl-O-tert.butyl-L-threonl)-23-O-isopropylideneuridine (1), 5-O-(N-tert.butyloxycarbonyl-O-benzyl-L-seryl)-2,3-O-isopropylideneuridine and (2), 5-O-(N-tert.butyloxycarbonyl-L-valyl)-2,3-O-isopropylideneuridine (3), and 5-O-(N-tert.butyloxycarbonyl-L-valyl)-2,3-O-isopropylideneuridine (4) were obtained in good yield after column chromatography on silica gel. The treatment of2 withTFA/CH2Cl2 (6:1) at room temperature for 30 min led to a selective removal of theBoc group without deblocking of the 2,3-O-isopropylidene group of uridine. Treatment of2 withTFA/H2O (5:1) at room temperature for 1 h, however, released bothBoc and 2,3-isopropylidene groups. TheZ group of1 was deprotected by catalytic hydrogenolysis over 10% Pd/C/ammonium formate.
Synthese von 5-O-Aminosäurederivaten des Uridins als potentielle Inhibitoren derUDP-Glukuronosyl-Transferase
Zusammenfassung In einem Versuch, potentielle Inhibitoren derUDP-Glukuronosyl-Transferase zu entwickeln, wurden einige 5-O-Aminosäurederivate des Uridins synthetisiert. N-GeschützteL-Aminosäuren wurden durch Veresterung mit der 5-O-Position des 2,3-isopropylidenuridins gekuppelt (Methode der symmetrischen Anhydride in der Gegenwart von 5-Dimethylaminopyridin). Solcherweise wurden 5-O-(N-Benzyloxycarbonyl-O-tert.butyl-L-threonly)-2,3-O-isopropylidenuridin (1), 5-O-(N-tert.Butyloxycarbonyl-O-benzyl-L-seryl)-2,3-O-isopropylidenuridin (2), 5-O-(N-tert.Butyloxycarbonyl-L-leucyl)-2,3-O-isopropylidenuridin (3) und 5-O-(N-tert.Butyloxycarbonyl-L-valyl)-2,3-O-isopropylidenuridine (4) nach Säulenchromatographie (Kieselgel) in guter Ausbeute hergestellt. Die Behandlung von2 mitTFA/CH2Cl2 (6:1) bei Zimmertemperatur (30 min) führte zu einer selektiven Abspaltung derBoc-Gruppe ohne Deblockierung der 2,3-O-Isopropylidengruppe des Uridins. Eine Behandlung von2 mitTFA/H2O (5:1) bei Zimmertemperatur für 1 Stunde führte hingegen zur Abspaltung sowohl derBoc als auch der 2,3-O-Isopropylidengruppe. DieZ-Gruppe von1 wurde durch katalytische Hydrogenolyse auf 10% Pd/C/Ammoniumformiat abgespalten.
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18.
Summary Two new terpenoid coumarins — tadzhiferin (I) and tadzhikorin (II) — have been isolated from the fruit ofFerula tadshikorum M. Pimen.On the basis of physicochemical and spectral investigations, the structure of 7-(9-hydroxy-3,7,11-trimethyldodeca-2,6,10-trienyloxy)coumarin is proposed for (I) and that of 7-(4-acetoxy-9-hydroxy-3,7,11-trimethyldodeca-2,6,10-trienyloxy)coumarin for (II).All-Union Scientific-Research Institute of Medicinal Plants, Moscow. M. V. Lomonosov State University. Botanical Garden, Moscow. Translated from Khimiya Prirodnykh Soedinenii, No. 5, pp. 593–599, September–October, 1976.  相似文献   

19.
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   

20.
Summary O-Acetylated flavonol glycosides have been isolated for the first time from the needles of the Scotch pine and the following structures have been established for them: 3,45,7-tetrahydroxy-3-methoxyflavone 3-O--D-(6-O-acetylglucopyranoside), 3,4,5,7-tetrahydroxy-3-methoxyflavone 3-O--D-(6-O-acetylgalactopyranoside), and 3,3,4,5,7-pentahydroxyflavone 3-O--D-(6-O-acetylglucopyranoside). The first two compounds have not previously been described in the literature.All-Union Scientific-Research Institute of Medicinal Plants, Moscow. Irkutsk Institute of Organic Chemistry, Siberian Branch of the Academy of Sciences of the USSR. I. M. Sechenov I Moscow Medical Institute. Translated from Khimiya Prirodnykh Soedinenii, No. 2, pp. 193–196, March–April, 1978.  相似文献   

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