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1.
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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2.
Chlorination of the title compound gave 5- and 3-chloro-2-hydroxy-4,6-dimethoxyacetophenone. The nitration of its acetate, followed successively by reduction, diazotization, and reaction with cuprous chloride, gave the 3-substituted series, 2-acetoxy-4,6-dimethoxy-3-nitroacetophenone, 3-amino-2-hydroxy-4,6-dimethoxyacetophenone, and 3-chloro-2-hydroxy-4,6-methoxyacetophenone, respectively. The orientation of substituents in the products was proved. The amino and chloro members of the isomeric 5-substituted series were availablevia 2-hydroxy-4,6-dimethoxy-5-phenylazoacetophenone, the product of the reaction of the title compound with benzenediazonium chloride.
Nitrierung, Aminierung und Halogenierung von Di-O-methylphloracetophenon
Zusammenfassung Chlorierung der Titelverbindung gab 5- und 3-Chlor-2-hydroxy-4,6-dimethoxyacetophenon. Die Nitrierung des Acetats, gefolgt von Reduktion, Diazotierung und Reaktion mit CuCl ergab die 3-substituierte Reihe: 2-Acetoxy-4,6-dimethoxy-3-nitroacetophenon, 3-Amino-2-hydroxy-4,6-dimethoxyacetophenon und 3-Chlor-2-hydroxy-4,6-dimethoxyacetophenon. Die Orientierung der Substituenten wird diskutiert. Die Amino- und Chlorderivate der isomeren 5-substituierten Reihe sind über 2-Hydroxy-4,6-dimethoxy-5-phenylacetophenon zugängig, dem Produkt der Reaktion der Titelverbindung mit Phenyldiazoniumchlorid.
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3.
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   

4.
The corresponding monophosphates, cyclophosphates, and , -diphosphates were obtained by phosphorylation of 1-(1, 4-dihydroxy-2-pentyl) thymine, 1-(1, 3-dihydroxy-2-propyl) uracil, and their derivatives with selective protection of one of the hydroxyl groups. 2-Cyanoethyl phosphate (CEP) in the presence of N, N-dicyclohexylcarbodiimide (DCC), polyphosphoric acid, and pyrophosphoryl chloride were used as phosphorylating agents. The dependence of the yields of the products of phosphorylation of 1-(1, 4-dihydroxy-2-pentyl) thymine with CEP on the ratio of the reacting substances and the reaction time was studied. The monophosphates were cyclized under the influence of DCC. In the case of 1-(1, 3-dihydroxy-2-propyl) uracil 1-phosphate a dimeric phosphate was obtained in addition to a cyclophosphate. The acid hydrolysis of the cyclophosphates was investigated.See [1] for communication V; see [2] for a preliminary communication.Deceased.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 5, pp. 678–683, May, 1978.  相似文献   

5.
The pK-values of the first and second degree of dissociation of 2.3-dihydroxy-6-methyl-3.5-dinitro-diphenylmethane, 2.3-dihydroxy-6-methyl-5-nitro-diphenylmethane, 2.3-dihydroxy-5.6-dimethyl-3-nitro-diphenylmethane, 2.4-dihydroxy-3. 5-dimethyl-3.5-dinitro-diphenylmethane, 2.4-dihydroxy-3. 5-dimethyl-5-nitro-diphenylmethane and 2.4-dihydroxy-3.5.5-trimethyl-3-nitrodiphenylmethane were determined in aqueous solution at 25°C by the spectrophotometric method. The observed pK-values are compared with those of 2-methyl-4.6-dinitro-phenol, 2-methyl-4-nitrophenol, 2.4-dimethyl-6-nitrophenol, 3.4-dimethylphenol and 2.4.6-trimethylphenol which serve as model compounds for the single phenolic units.  相似文献   

6.
2,2-Bi[5-(2,5-dihydroxy-3,4,6-trichlorophenyl)thiazole] and 6-(2,5-dihydroxy-3,4,6-trichlorophenyl)-2-imino-3,4-dihydro-4H-1,4-thiazin-3-thione are synthesized from 2,5-dihydroxy-3,4,6,7-tetrachloro-2,3-dihydrobenzo[b]furan and dithiooxalyldiamide. The products are oxidized by FeCl3 to the corresponding trichloro-1,4-benzoquinonyl-substituted sulfur-containing heterocycles. N-Methylation of 2,2-bithiazole by dimethyl sulfate gives 2,2-bi[5-(2,5-dihydroxy-3,4,6-trichlorophenyl)-3-methylthiazolium] bismonomethyl sulfate. The last compound is readily transformed to 2,2-bi[5-(2-hydroxy-5-oxido-3,4,6-trichlorophenyl)-3-methylthiazolium] bisbetaine.Riga Technical University, Riga LV-1048, Latvia, Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 7, pp. 988–992, July, 1999.  相似文献   

7.
The following tricyclic heterocyclic compounds are synthesized: 2-methylthiazolov (5, 4-e) benzo-1, 2, 3thiadiazole, 2-methylthiazolo (4, 5-e) benzo-1, 2, 3-thiadiazole, 2-methylthiazolo (4, 5-g) benzo-1, 2, 3-thiadiazole, and 2-methylthiazolo (5, 4-g) benzo-1, 2, 3-thiadiazole. The quaternary salts of these bases are used to prepare symmetrical and unsymmetrical trimethinecyanines and dimethinemercocyanines containing N-ethylrhodanine residues. The absorption maxima of these dyes are shifted toward the long-wave region as compared with the corresponding thiacyanines.  相似文献   

8.
1,2,5-Trimethyl-4-(9-fluorenylidene)piperidine, which is formed by condensation of fluorene with 1,2,5-trimethyl-4-piperidone, is converted catalytically to 9(2,5-dimethyl-4-pyridyl)fluorene, from which 2-methylpyrido[4,5-a]fluoranthene and its demethylated analog were obtained by catalytic dehydrocyclization. Oxidation of 9-(2,5-dimethy1-4-pyridyl)fluorene gave 9-(2,5-dimethyl-4-pyridyl)9-fluorenol and fluorene-9-spiro-4-(6-oxo-2-carboxypyrido[4,5-c]-4-6-dihydrofuran). 6-Methyl-2-phenyl-7-(9-fluorenyl)indolizine was synthesized by the Chichibabin method.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 8, pp. 1087–1090, August, 1978.  相似文献   

9.
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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10.
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   

11.
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   

12.
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   

13.
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   

14.
Acetovanillon and the known flavonoids irisolidone, irigenin, irisolone, tectorigenin and dihydroquercetin-7.3-dimethylether were detected in the rhizomes of Iris germanica. Also a few unknown compounds could be isolated and their structure elucidated; 9-methoxy-7-(3.4.5-trimethoxyphenyl)-8H-1.3-dioxolo[4.5-g] [1]-benzopyran-8-on (=5.3.4.5-tetramethoxy-6.7-methylenedioxyisoflavone (III A); 9-methoxy-7-(3.4-dimethoxyphenyl)-8H-1.3-dioxolo[4.5-g] [1]-benzopyran-8-on (=5.3.4-trimethoxy-6.7-methylenedioxyisoflavone(III B); 9-hydroxy-7-(p-hydroxyphenyl)-8H-1.3-dioxolo[4.5-g] [1]-benzopyran-8-on (=5.4-dihydroxy-6.7-methylenedioxyiosoflavone (IX); 5.7-dihydroxy-3-(3-hydroxy-4-methoxyphenyl)-6-methoxy-4H-1-benzopyran-4-on (=5.7.3-trihydroxy-6.4-dimethoxyisoflavone (XI B); 5.7-dihydroxy-3-(4-hydroxy-3-methoxyphenyl)-6-methoxy-4H-1-benzopyran-4-on (=5.7.4-trihydroxy-6.3-dimethoxyisoflavone (XI C).The structure determination was effected by combined spectroscopical and chemical methods.

Herrn Prof. Dr.F. Hecht mit den besten Wünschen zum 70. Geburtstag gewidmet.  相似文献   

15.
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   

16.
Conclusions On the basis of the rates of their acid hydrolysis, their optical activities, and their IR spectra, it has been established that the glycosides ofAesculus hippocastanum L. are (SK-1) 3--L-arabofuranosyloxy-5,7,4-trihydroxyflavone, (SK-2) 3--L-rhamnofuranosyloxy-5,7,4-trihydroxyflavone, (SK-3) 3--L-arabofuranosyloxy-5,7,3,4-tetrahydroxyflavone, and (SK-4) 3--L-rhamnofuranosyloxy-5,7,3,4-tetrahydroxyflavone.The glycoside SK-3 is identical with avicularin isolated from the leaves ofPsidium quajava [5]. The complete structures of the other three glycosides have been established for the first time.Khimiya Prirodnykh Soedinenii, Vol. 5, No. 1, pp. 5–7, 1969  相似文献   

17.
The decomposition of various symmetric and unsymmetric azo-initiators (1,1-dichloro-1,1-diphenyl-1,1-azoethane, 2,2-dichloro-2,2-azopropane, 1,1-dichloro-1,1-azocyclohexane, 2,2-diacetoxy-2,2-azopropane, 1,1-diacetoxy-1,1-diphenyl-1,1-azoethane, 1,1-diacetoxy-1,1-azocyclohexane, 2,2-dipropionoxy-2,2-azopropane, 2,2-dicapronoxy-2,2-azopropane, 4,4-dimethyl-1,4-azobutyrolactone, azoisobutyronitrile, 2-t-butylazo-2-cyanobutan, 2-t-bytylazo-1-cyanocyclohexan) in solution was studied in dependence of temperature. Volumetry and differential-scanning-calorimetry (DSC) were used to determine decomposition rates; first order kinetics was found in all cases.
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18.
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   

19.
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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20.
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   

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