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1.
The structure of bromovasicol has been established on the basis of the results of x-ray structural analysis as 4-bromo-2-(3-hydroxy-2-oxypyrrolinomethl)aniline. Vasicol was isolated from the plantPeganum harmala in the form of 2-(3-hydroxy-2-oxopyrrolidinomethyl)aniline.Institute of the Chemistry of Plants Substances, Uzbek SSR Academy of Sciences, Tashkent. Translated from Khimiya Prirodnykh Soedinenii, No. 1, pp. 18–23, January–February, 1989.  相似文献   

2.
The oxidation of cumene and a cumene-nitrobenzene (12) mixture at 60°C in the presence of AIBN and acetylacetonates of Co(II), Cu(II), Fe(II), Fe(III), V(III), Cr(III), Mn(III) and MoO 2 2+ has been investigated.
(12) 60°C - Co(II), Cu(II), Fe(II), Fe(III), V(III), Cr(III), Mn(III), MoO 2 +2 .
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3.
Oxidation selectivity of phenol and its O-protected derivatives in the Hamilton system has been studied. Modification of OH groups by acyl substituents and addition of -cyclodextrin markedly enhance paraselectivity of this reaction.
O- . , OH- - - .
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4.
It has been found that calcium nitride possesses a high catalytic activity in the isotope exchange of nitrogen. The catalytic activity of nitrides is shown to be independent of the heat of their formation. The effect of H2 and O2 on the isotope exchange of nitrogen is studied.
. . H2 O2 .
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5.
The reaction of 2-(N,N-dimethylaminomethylene)indolin-3-one and 2-methyl-3-ethoxycarbonyl-5-(N,N-dimethyl aminomethylene)-2-pyrrolin-4-one with acyl halides was used to synthesize immonium salts, the aqueous hydrolysis of which leads to 2-formyl-3-hydroxyindole and 4-hydroxy-5 formylpyrrole derivatives. -Cyano--(2-indolyl)- and -cyano--(5-pyrrolyl)acrylic acid derivatives were synthesized by reaction of immonium salts of the pyrrole series, 4 acyloxy-5-formylpyrrole and 2-formyl-3-acyloxyindole derivatives, with compounds that contain an active methylene group.See [1] for Communication 63.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 3, pp. 343–348, March, 1991.  相似文献   

6.
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   

7.
A relation between the type of vanadium environment and the chemical shift anisotropy in the51V-NMR spectra has been established. The results obtained are compared with spectra of real catalysts.
51V , .
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8.
Infrared microthermography was used to study dynamically the decomposition of single cristalline platelets (surface 1 cm2) of copper sulfate pentahydrate. The measurement of the local self cooling allows to plot the thermal profiles in front of the reaction and yields the temperature of the reactive interface. It is also possible to plot the thermal maps of the samples for their evolution, and thereby gets permitted knowledge of the gradients of temperature in those reactions. The evolution of these values with pressure, orientation of the platelets or of the reactive interface is envisaged.
Zusammenfassung Die Infrarotmikrothermographie wurde zur dynamischen Untersuchung der Zersetzung von Kupfersulfat-Pentahydrat in Form von Einkristallplättchen (Oberfläche 1 cm2) herangezogen. Die Messung der lokalen Selbstabkühlung ermöglicht, die thermischen Profile in der Reaktionsfront aufzuzeichnen und die Temperatur der reaktiven Grenzfläche zu erhalten. Es ist auch möglich, die thermischen Karten der Proben darzustellen und damit eingehende Kenntnisse über die Temperaturgradienten bei solchen Reaktionen zu gewinnen. Untersuchungen sind vorgesehen, um zu klären, wie Druck und Orientierung der Plättchen oder der reaktiven Grenzfläche diese Werte beeinflussen.

( 1 2) . . . . .
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9.
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   

10.
TG and DTA of the compounds Mn(phen)2X2 (where X=CN,CNO, NCS and NCSe), Mn(phen) (NCS)2, Mn(NCS)2 and Mn(NCSe)2 (wherephen=1,10 phenanthroline) are reported and discussed. Decomposition schemes are proposed based on TG and DTA results and, where possible, the analysis and properties of intermediates formed during thermal breakdown. The decomposition of thiocyanate and selenocyanate ligands is observed to lead to an apparent slight increase in sample weight. This phenomenon is discussed in relation to buoyancy changes resulting from the release of sulphur or selenium vapours.
Zusammenfassung TG und DTA Untersuchungen der Verbindungen Mn(phen)2X2 (X=CN, CNO, NCS und NCSe), Mn(phen) (NCS)2, Mn(NCS)2 und Mn(NCSe)2 (phen =1.10 Phenantrolin) werden beschrieben. Anhand der TG- und DTA-Ergebnisse werden Zerzetzungsschemata vorgeschlagen und wenn möglich, Analyse und Eigenschaften der im Laufe der thermischen Zersetzung entstandenen Zwischenprodukte angegeben. Es wurde beobachtet, da\ die Zersetzung der Thiocyanat- und Selenocyanatliganden zu einer scheinbaren schwachen Zunahme des Probengewichts führt. Dieses PhÄnomen wird im Zusammenhang mit infolge der Abspaltung von Schwefel- oder SelendÄmpfen auftretenden Änderungen des Auftriebs diskutiert.

Résumé On décrit et discute la TG et l'ATD des composés Mn(phén)2X2 (X=CN, CNO, NCS et NCSe), Mn(phén) (NCS)2, Mn(NCS)2 et Mn(NCSe)2 (oùphén=1,10 phénantroline). On propose des schémas de décomposition à partir des résultats de TG et d'ATD et, si possible, on donne l'analyse et les propriétés des produits intermédiaires formés lors de la décomposition thermique. On a observé que la décomposition des ligands de thiocyanate et de sélénocyanate entraine une faible augmentation apparante du poids du prélèvement. On explique ce phénomène par les variations de poussée résultant du dégagement de vapeurs de soufre ou de sélénium.

()22, () (NCS)2, Mn(NCS)2 Mn(NCSe)2, X=CN, CNO, NCS, NCSe =1.10. , , - , . . - , .


We wish to express our thanks to Professor S. C. Bevan for helpful advice, particularly in connection with the buoyancy effect noted for thiocyanate and selenocyanate complexes.  相似文献   

11.
A number of 7-O-aminoacyl derivatives of isoflavones have been obtained by the interaction of 2-R-7-hydroxy-3,4-ethylenedioxyisoflavones with the symmetrical anhydrides of N-protected amino acids.Kiev Tara Shevshenko University, Ukraine, 252033, Kiev, Ul. Vladimirskaya, 64, tel./fax 225-12-73. Translated from Khimiya Prirodnykh Soedinenii, No. 3, pp. 334–338, May–June, 1999.  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 reaction of acidic form of the substituted icon phthalocyanine complex (3-PhS- 5-But)4pcFe (pcFe) with dioxygen in o-dichlorobenzene in the presence of dichloroacetic acid (HX) was investigated. The oxidation of HpcFeX gives the corresponding radical cation, which was confirmed by the stoichiometry of reduction of the product formed in this reaction with a two-electron reducing agent. The kinetic equation obtained on the basis of dependences of the oxidation rate on the HpcFeX, HX, and O2 concentrations are consistent with the reaction mechanism that implies the formation of a HpcFeX complex with O2 and its transformation to give a radical cation under the action of HX.Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 8, pp. 1592–1597, August, 2004.  相似文献   

14.
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   

15.
Alkylation of 5-(3-nitro-4-hydroxyphenyl)-10,15,20-triphenylporphyrin with chloropyridines[2,6-dichloromethyl-and 2-chloromethyl-6-(2-nitrophenoxymethylpyridine)] as well as condensation by a mixed-aldehyde method starting with formylpyridines [2-(2-nitro-4-formylphenoxymethyl)-6-(2-nitrophenoxy-methyl-) or 2,6-di(2-nitro-4-formylphenoxymethyl)pyridine], benzaldehyde, and pyrrole are used to synthesize previously unknown podand-porphyrins containing from one to four peripheral chelates.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 4, pp. 475–481, April, 1991.  相似文献   

16.
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   

17.
Summary Conformational properties of two nucleoside analogs, namely nebularine and isoguanosine have been investigated by using PCILO (Perturbative Configuration Interaction using Localized Orbitals) method. Nebularine (9--ribofurnosyl purine) is a naturally occurring purine nucleoside which is structurally similar to adenosine and it inhibits the growth of tumor cells and influenza B virus. Isoguanosine is one of the two naturally occurring analogs of guanosine. Both C2-endo and C3-endo sugar puckerings have been considered for both the molecules with preselected values of torsion angles around C2–O2 and C5–O5 bonds. The results indicate that nebularine has conformational preferences very similar to those of its parent nucleoside, adenosine; whereas the conformational properties of isoguanosine are very different from those of guanosine as well as adenosine. The important implications of these results have been discussed in terms of the biological activity of these molecules.  相似文献   

18.
Chemical transformations and spectral characteristics have enabled us to establish the structure and configurations of three coumarins: (+)-2,2-dimethyl-3-hydroxy-3,4-dihydropyrano(5,6:6,7)coumarin (I); (+)-4-hydroxy-5-(1-hydroxy-1-methylethyl)-4,5-dihydrofuro(2,3:6,7)coumarin (II); and (+)-4-hydroxy-5-(1-glucopyranosyloxy-1-methylethyl)-4,5-dihydrofuro(2,3:6,7)-coumarin (III) isolated from the roots ofSmyrnopsis aucheri Karjag. This is the first time that these compounds, which have been called smyrinol, smyrindiol, and smyrindioloside, have been detected in nature.Institute of Chemistry of Plant Substances, Uzbekistan Republic Academy of Sciences, Tashkent. Azerbaidzhan State University, Baku. Translated from Khimiya Prirodnykh Soedinenii, No. 1, pp. 36–40, January–February, 1992.  相似文献   

19.
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   

20.
Zusammenfassung Eine flotations-spektrophotometrische Methode zur Bestimmung des Zirkoniums in Stählen mittels des Dinatriumsalzes der 2,6-Dichlor-4-hydroxy-3, 3-dimethylfuchson-5,5-dicarbonsäure (CAB) wurde ausgearbeitet. Der molare Extinktionskoeffizient beträgt 3,3×104, die spezifische Absorptiona=0,33. Der Vorteil der bearbeiteten Methode ist die Möglichkeit, Zirkonium (IV) neben der hundertfachen Menge Hf(IV) zu bestimmen.
Flotation spectrophotometric method for determination of zirconium by means of eriochrome azurol B
Summary A flotation spectrophotometric method for determining zirconium in steels by means of the disodium salt of 2, 6-dichloro-4-hydroxy-3,3-dimethylfuchsone-5, 5-dicarbonic acid (CAB) was worked out. The molar extinction coefficient is 3.3×104. The specific absorption wasa=0.33. The advantage of the method is the possibility of determining zirconium(IV) besides the hundredfold amount of Hf(IV).
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