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1.
Convenient methods for the synthesis of chiral 2,3-seco-2-deoxynucleosides were developed. An isopropylidene protective group was used to block the 3,5-hydroxy groups in 2,3-seco-uridine. Conversion of the hydroxymethyl group to a methyl group was accomplished by chlorination with a mixture of CCl4 and Ph3P with subsequent reduction with n-Bu3SnH. 2,3-seco-2-Deoxyuridine was obtained after deacetonation. The (S) enantiomer was similarly synthesized starting from 1-(-D-arabinofuranosyl)uracil. 3-O-tert-Butyldimethylsilyl-5-O-(p-monomethoxytrityl)-2,3-seco-2-deoxyuridine, which has optically active centers at C(1) and C(4), was also synthesized.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 6, pp. 822–826, June, 1988.The authors thank Professor M. Ya. Karpeiskii for his constant interest in this research.  相似文献   

2.
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   

3.
The compatibility of a lauric fat with several milk fat fractions (MF) was investigated. The enthalpy of crystallization was measured by differential scanning calorimetry (DSC). These values were related to the corresponding values calculated for an Ideal Blend. The different compatibility of the milk fat fractions with the lauric fat could be shown by this method very clearly.
Untersuchungen zur Mischbarkeit/Verträglichkeit von Milchfettfraktionen mit laurischen Fetten
Zusammenfassung Die Mischbarkeit/Verträglichkeit von Milchfettfraktionen mit einem laurischen Fett wurde differenzkalorimetrisch untersucht. Die Auswertung der Befunde bezieht sich auf die entsprechenden Rechnungswerte einer Idealen Mischung. Es wurde nachgewiesen, da sich diese Milchfette deutlich in ihrer Mischbarkeit unterscheiden.

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4.
Research on synthesis of polycyclic spirans of the 1, 6-dioxaspiro-[4, 4]nonane group is continued. Electrolysis of methanol solutions of 2-furylcyclopentanol, 2-(5-methyl-furfuryl)cyclopentanol, and 2-furfuryl-1-indanol, gives, by intramolecular alkoxylation, spiro{perhydrocyclopenta[b]furan-2, 2-(5dihydrofuran)}, spiro{perhydrocyclopenta[b]furan-2, 2-(5-methoxy-5-methyl-2, 5-dihydrofuran)}, and spiro{2, 3, 3a, 8b-tetrahydro-4H-indeno[1, 2-b]furan-2, 2-(5-methoxy-2, 5-dihydrofuran)}, hitherto undescribed in the literature. Depending on the conditions, catalytic hydrogenation of these gives: spiro{perhydiocyclopenta[b]furan-2, 2-(5-methoxytetrahydrofuran)}, spiro{2, 3a, 8b-tetrahydro-4H-indeno[1, 2-b]furan-2, 2-(5-methoxytetrahydrofuran)}, spiro{perhydrocyclopenta[b]furan-2, 2-tetrahydrofuran}, and spiro{2, 3, 3a, 8b-tetrahydro-4H-indeno[1, 2-b]furan-2, 2-tetrahydrofuran}.For Part XXXI see [1].  相似文献   

5.
Summary Complexes of adenosine-5-triphosphate, adenosine-5-monophosphate, guanosine-5-monophosphate, inosine-5-monophosphate, cytidine-5-monophosphate and uridine-5-monophosphate with vanadyl ion, have been studied in the solid state by i.r. spectroscopy and magnetochemically. All complexes have normal magnetic moments, very close to the spin-only values. From the i.r. spectra it is suggested that the vanadyl ion is interacting with adenosine-5-triphosphate, through the N-1 of the purine ring, with adenosine-5-monophosphate, guanosine-5-monophosphate, inosine-5-monophosphate, through the N-7 of the purine ring, with cytidine-5-monophosphate through the N-3 of the pyrimidine ring, and most probably through the phosphate group with uridine-5-monophosphate. The complexes of vanadyl ion with the nucleotides are probably polymeric.  相似文献   

6.
A gradientless airtight glass reactor supplied with a detachable chamber for the catalyst has been developed. It is designed for investigations on the kinetics of heterogeneous catalytic processes and the determination of catalytic activities at atmospheric and reduced pressures by the flow-circulation and quasi-static techniques.
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7.
The centers (g1=1,999; g2=1.984 and g3=1.979) assigned to the stabilization of photoinduced O holes on coordinatively unsaturated Ti4+ ions, not interacting with CO up to 250 K, are shown to be the activation centers of the molecular oxygen as an complex (g1=2.046; g2=2.008) for CO oxidation even at 87 K with the formation of CO 3 (g=2.0285, g=2.005).
, (g1=1,999; g2=1,984; g3=1,979), O Ti4+, CO 250° K (g1=2,046; g2=2,008) CO 87°K CO 3 (g=2,0285) g=2,0055).
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8.
Methyl 1-aryl-3-aroyl-4,5-dioxo-4,5-dihydro-1H-pyrrole-2-carboxylates react with N-substituted 3-amino-5,5-dimethyl-2-cyclohexenones to give 4-hydroxy-1-aryl-3-aroyl-6,6-dimethyl-1, 2,3,4,5,5,6,7-octahydro-1H,2H-indole-3-spiro-2-pyrrole-2,4,5-triones. The structure of the products was proved by the X-ray diffraction data for the 1-cyclohexyl derivative.__________Translated from Zhurnal Organicheskoi Khimii, Vol. 40, No. 12, 2004, pp. 1840–1845.Original Russian Text Copyright © 2004 by Bannikova, Maslivets, Aliev.For communication XLVIII, see [1].  相似文献   

9.
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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10.
Condensation of 5- or 6-nitroindoline with L-arabinose gave 1--L-arabinopyranosyl-5 (or 6)-nitroindolines, which, after acetylation, dehydrogenation, and removal of the protective groups, are converted to 1--L-arabinopyranosyl-5(or 6)-nitroindoles and then to the corresponding amino derivatives. 1--L-Arabinopyranosyl-6-nitro-3-bromo-(iodo)indoles were obtained. The selective 2-O- and 3-O-deacetylation of 1-(2, 3, 4-tri-O-acetyl)--L-arabinopyranosyl-6-nitroindole was accomplished.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 2, pp. 224–229, February, 1979.  相似文献   

11.
2,2,4-Trichloro-6-phenyl-4,5-dipyrimidinyl, for which nucleophilic substitution with piperdine under various conditions was studied, was obtained from 2,2,4-trioxo-6-phenyl-1, 1,2,2,3,4-hexahydro-4,5-dipyrimidinyl. It is shown that there is an appreciable difference in the rates of substitution of the first, second, and third chlorine atoms, and this made it possible to obtain reaction products that contain one, two, and three piperidino groups. The chlorine atom in the 4 position is replaced initially, after which the chlorine atom in the 2 position undergoes substitution. The structures of the compounds were proved by chemical transformations and analysis of the PMR spectra.See [1] for communication 69.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 6, pp. 821–826, June, 1979.  相似文献   

12.
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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13.
The ionization potentials of a number of isomeric dipyridyls and diquinolyls were determined. The differences in their values make it possible to establish the site of fusion of the rings in the 2,2, 3,3, and 4,4 positions of the system. The absence of an appearance potential for the fragment ion, the existence of which is due to cleavage of the interannular bond in the doubled hetaryl compounds, constitutes evidence for its double-bond character.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 6, pp. 812–814, June, 1976.  相似文献   

14.
Relative hydrogenation reactivity of the two carbonyl groups of methylcyclohexane-1,4-dione can be estimated beside that of two related compounds, 2- and 3-methyl-cyclohexanones. The reaction is accompanied with hydrogenolysis on Pt and Pd. The less hindered 4-carbonyl group is selectively hydrogenolyzed.
-1,4- , 2- 3-. Pt Pd. 4- .
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15.
A study has been made of natural C-methylflavones and their dealkylated analogues: 5-hydroxy-4,7-dimethoxy-7-methylflavone (noreucalyptin); 4,5,7-trihydroxy-6-methylflavone; 5-hydroxy-4,7-dimethoxy-6,8-dimethylflavone (eucalyptin); 4,5-dihydroxy-7-methoxy-6,8-dimethylflavone (sideroxylin); 4,5,7-trihydroxy-6,8-dimethylflavone; 4,5,6-trihydroxy-3-methoxy-8-methylflavone (silpin) and 3,4,5,6-tetrahydroxy-8-methylflavone.All-Union Scientific-Research Institute of Medicinal Plants, Moscow. Translated from Khimiya Prirodnykh Soedinenii, No. 3, pp. 306–309, May–June, 1984.  相似文献   

16.
The rate constants and activation energies for homolytic dissociation of 2,2-di[ ()-naphthyl]-, 2,2-diquinolinyl-, and 2,2-di(9-acridinyl)-4,4,5,5-tetraphenyldiimidazolyls in toluene in the presence of,-diphenyl--picrylhydrazine were determined. The degrees of dissociation of the diimidazolyls were found. The effect of substituents on the stability of imidazolyl radicals is discussed.See [1] for communication III.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 11, pp. 1536–1539, November, 1974.  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.
The thermal decompositions of the following compounds were studied: Ni(NCO)2(3-Etpy)4. (I), Ni(NCO)2(3-Clpy)4 (II), Ni(NCO)2(3-Brpy)4 (III), Ni(NCO)2(3-NH2py)4 (IV), Ni(NCO)2(3-Clpy)2·2H2O (V) and Ni(NCO)2(3-Brpy)2·2H2O (VI). The release of volatile ligands (3-Rpy and H2O) is a two-step process, Ni(NCO)2(3-Etpy)2 (VII), Ni(NCO)2(3-Clpy)2 (VIII), Ni(NCO)2(3-Brpy)2 (IX) and Ni(NCO)2(3-NH2py)2 (X) being formed as intermediate complexes. The loss of the last molecules of volatile 3-Rpy ligands is accompanied by NCO ligand decomposition. The spectral and magnetic data indicated pseudooctahedral configuration for all complexes I-X.
Zusammenfassung Die thermische Zersetzung der folgenden Verbindungen wurde untersucht: Ni(NCO)2(3-Etpy)4 (I), Ni(NCO)2(3-Clpy)4 (II), Ni(NCO)2(3-Brpy)4 (III), Ni(NCO)2(3-NH2py)4 (IV), Ni(NCO)2(3-Clpy)2·2H2O (V) und Ni(NCO)2(3-Brpy)2·2H2O (VI). Die flüchtigen Liganden (3-Rpy und H2O) werden in zwei Schritten abgegeben, wobei Ni(NCO)2(3-Etpy)2 (VII), Ni(NCO)2(3-Clpy)2 (VIII), Ni(NCO)2(3-Brpy)2 (IX) und Ni(NCO)2(3-NH2py)2 (X) als intermediäre Komplexe gebildet werden. Die Abgabe der letzten Moleküle der flüchtigen 3-Rpy-Liganden geht mit der Zersetzung des NCO-Liganden einher. Die spektrometrischen und magnetischen Daten weisen auf eine pseudooktaedrische Konfiguration aller Komplexe (I-X) hin.

: Ni(NCO)2(3-Etpy)4 (I), Ni(NCO)2(3-Clpy)4 (II), Ni(NCO)2(3-Brpy)4 (III), Ni(NCO)2(3-NH2py)4 (IV), Ni(NCO)2(3Clpy)2·2H2O(V) Ni(NCO)2(3-Brpy)2·2H2O (VI). (3-Rpy H2O) , Ni(NCO)2(3-Etpy)2 (VII), Ni(NCO)2(3-Clpy)2 (VIII), Ni(NCO)2(3-Brpy)2 (IX) Ni(NCO)2(3NH2py)2 (X). . .
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19.
The crotonic condensation of 2, 5-diformylthiophene with various aromatic and heterocyclic methyl ketones has given 15 , -unsaturated diketones. By the reaction of the latter with phenylhydrazine, ten 2, 5-di(1-phenyl-3-R-2-pyrazolin-5-yl)thiophenes possessing a bright blue-violet or green luminescence have been synthesized.  相似文献   

20.
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   

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