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1.
Summary 2-O-Ethyluracil and 2-O-ethylthymine were silylated with 1,1,1,3,3,3-hexamethyldisilazane and condensed in the presence ofTMS triflate with 2,3-dideoxy-3-fluoro-D-erythro-pentofuranoside, 3-azido-2,3-dideoxy-D-erythro-pentofuranoside, and 2,3-dideoxy-3-phthalimido--D-erythro-pentofuranose derivatives to give the corresponding 2-O-ethyl nucleosides. Deprotection with saturated methanolic ammonia afforded the 2,3-dideoxy-3-fluoro-2-O-ethyluridines, whereas 3-azido-2,3-dideoxy-3-O-ethyluridine was obtained by deprotection with tetrabutylammonium fluoride in tetrahydrofuran. 3-Amino-2,3-dideoxy-3-O-ethyluridine could be obtained only by treatment of the corresponding 3-azido nucleoside with triphenylphosphine in pyridine. 3-Deoxy-2-O-ethyl-3-fluorothymidine (6b) showed moderate activity against HIV-1.
Synthese von 2-O-Ethyl-Analogen von 3-Azido- und 3-Fluor-23-dideoxyuridinen und Bestimmung ihrer biologischen Aktivität gegenüber HIV
Zusammenfassung 2-O-Ethyluracil und 2-O-Ethylthymin wurden mit 1,1,1,3,3,3-Hexamethyldisilazan silyliert und in Gegenwart vonTMS-triflat mit 2,3-Dideoxy-3-fluoro-D-erythro-pentofuranosid, 3-Azido-2,3-dideoxy-D-erythro-pentofuranosid und 2,3-Dideoxy-3-phthalimido--D-erythro-pentofuranosederivaten zu den entsprechenden 2-O-Ethyl-Nucleosiden umgesetzt. Entfernung der Schutzgruppe mit gesättigter methanolischer Ammoniaklösung lieferte 2,3-Dideoxy-3-fluor-2-O-ethyluridin; 3-Azido-2,3-dideoxy-3-O-ethyl-uridin wurde durch Entschützung mit Tetrabutylammoniumfluorid in Tetrahydrofuran erhalten. 3-Amino-2,3-dideoxy-3-O-ethyl-uridin konnte nur durch Behandeln des entsprechenden 3-Azido-Nucleosids mit Triphenylphosphin in Pyridin hergestellt werden. 3-Deoxy-2-O-ethyl-3-fluor-thymidin (6b) zeigt geringe Aktivität gegenüber HIV-1.
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2.
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   

3.
Es wird die Darstellung einer Anzahl von 3,3-Methylen-bis-(4-hydroxy-1-thiacumarinen), von 3,3-Aryliden-bis-(4-hydroxy-1-thiacumarinen) mit verschiedenen Substituenten im aromatischen Ring und einiger 3,3-Aryliden-4,4-epoxydithiacumarine beschrieben. Die Bildung von Anhydroverbindungen bei Verwendung von Salicyladehyd als Aldehydkomponente bei derartigen Kondensationen wird diskutiert.The synthesis of a number of 3,3-methylene-bis-(4-hydroxy-1-thiacumarins), 3,3-arylidene-bis-(4-hydroxy-1-thiacumarins) carrying various substituents in the arylidene nucleus as well as that of the corresponding 3,3-arylidene-4,4-epoxydithiacumarins is described. The formation of anhydrocompounds when salicylaldehyde is the aldehyde component in such condensations is discussed.

Teil der DissertationP. S. J. zur Erlangung der Würde eines Ph. D. der Karnatak University.  相似文献   

4.
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   

5.
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   

6.
Conclusions The reaction of 1,2-bis(methyldimethoxysilyl)ethane and the corresponding ethylene and acetylene derivatives with bis(2-hydroxyethyl)methylamine gives 1,2-bis(2,6-dimethyl-1,3-dioxa-6-aza-2-silacyclooctyl-2)ethane and the corresponding ethylene and acetylene derivatives. Analogously, 1,2-bis(vinyldimethoxysilyl)acetylene gave 1,2-bis(2-vinyl-6-methyl-1,3-dioxa-6-aza-2-silacyclooctyl-2)acetylene.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 6, pp. 1420–1421, June, 1988.  相似文献   

7.
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   

8.
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   

9.
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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10.
Phosphorus pentasulfide reacts with the amides and substituted amides of 5-nitrofuran-2-carboxylic and 3-(5-nitrofuryl-2) acrylic acids in ethyl acetate to give the corresponding thioamides. Some amides of 5-nitrofuran-2-carboxylic and 3-(5-nitrofuryl-2) acrylic acids are synthesized for the first time. Iodine oxidation of 5-nitrofuran-2-thiocarboxamide gives 3, 5-bis (5-nitrofuryl-2)-1, 2, 4-thiazole.  相似文献   

11.
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   

12.
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   

13.
Zusammenfassung Cyclohexanon bzw. Cyclopentanon sowie ihre durch Aldolreaktion entstehenden Dimeren reagieren mit Harnstoff im sauren Medium zu 5,6,7,8-Tetrahydrospiro[cyclohexan-1,4(1H)-chinazolin]-3(2H)-onen (2) bzw. zum Dihydrospiro-(cyclopentan-1,4(1H)-5H-cyclopenta[d]pyrimidin)-2(3H)-on (10). Substituierte Harnsotoffe geben Gemische der isomeren 5,6,7,8-Tetrahydro- und 4a,5,6,7-Tetrahydroverbindungen (2, 3) bzw. 6,7-Dihydro-tH- und 5,6-Dihydro-4aH-verbindungen (10, 11). Charakteristisch für2 (3),10 (11) ist die Reaktivität der Kernstellen 8 bzw. 7 gegenüber elektrophilen Agentien (2f-v, 3f-j, 9 a-i, 10 d-f). Äthylmalonsäurebis-trichlorphenylester bzw. Formaldehyd und prim. Amine führen2 in ein partiell hydriertes 1H-Pyrido[3,2,1-ij]chinazolintrion (6) bzw. 1H-Pyrimido[5,6,1-ij]chinazolinon (7) über. Die 1-Alkylverbindungen (2) geben mit Formaldehyd und primären Aminen Hexahydro-8a-hydroxy-4a,8-propanospiro-(cyclohexan-1,4(1H)-pyrido[4,3-d]pyrimidin)-2(3H)-one (8).
Heterocycles, XXV: tetrahydrospiro [cyclohexane-1,4(1H)-quinazoline]-2(3H)-ones
Cyclohexanone and cyclopentanone, resp., as well as their dimers (formed by aldol reaction) react with urea in the presence of acids to 5,6,7,8-tetrahydrospiro[cyclohexane-1,4-(1H)-quinazoline]-3(2H)-ones (2) and to the dihydrospiro-(cyclopentane-1,4(2H)-5H-cyclopenta[d]pyrimidine)-2(3H)-one (10), resp. Substituted ureas give the isomeric 5,6,7,8-tetrahydro- and 4a,5,6,7-tetrahydro compounds (2, 3), and 6,7-dihydro-5H- and 5,6-dihydro-4aH-compounds (10, 11), resp. Characteristic for2 (3),10 (11) is the reactivity of the nuclear places 8 and 7 with electrophilic agents (2f-v, 3f-j, 9a-i, 10d-f). Ethylmalonic acid bistrichlorophenylester resp. formaldehyde and primary amines react with2 to the partially-hydrogenated 1H-pyrido[3,2,1-ij]-quinazolinetrione (6) and 1H-pyrimido[5,6,1-ij]-quinazolinone (7), resp. The 1-alkyl compounds (2) give with formaldehyde and primary amines hexahydro-8a-hydroxy-4a, 8-propanospiro(cyclohexane-1,4-(1H)-pyrido[4,3-d]pyrimidine)-2(3H)-ones (8).
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14.
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   

15.
Obtusinin (1) has been synthesised by the reaction of 6-methoxy-7-(3-methylbut-2-enyloxy)-2H-1-benzopyran-2-one (3) with OsO4. Synthesis of 7-(3-hydroxymethylbut-2-enyloxy)-6-methoxy-2H-1-benzopyran-2-one (2) has been achieved by the regiospecific oxidation of3 with SeO2 followed by reduction of the formed aldehyde with KBH4.
Synthese von Obtusinin und 7-(3-Hydroxymethylbut-2-enyloxy)-6-methoxy-2H-1-benzopyran-2-on
Zusammenfassung Obtusinin (1) wurde über 6-Methoxy-7-(3-methylbut-2-enyloxy)-2H-1-benzopyran-2-on (3) mit OsO4 synthetisiert. Die Darstellung von 7-(3-Hydroxymethylbut-2-enyloxy)-6-methoxy-2H-1-benzopyran-2-on (2) wurde mittels regioselektiver Oxidation von3 mit SeO2, gefolgt von Reduktion des gebildeten Aldehyds mit KBH4, bewerkstelligt.
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16.
Summary The kinetics of replacement of 4,4-bipyridine, (4,4-bipy), and 4-cyanopyridine, (4-CNpy), by cyanide in [Fe(CN)5-(4,4-bipy)]3-. at 298 K have been studied in binary aqueous mixtures containing different amounts of t-butanol, methanol, glycerol, ethyleneglycol and sucrose. The plots of logarithms of the limiting rate constantsversus the mole fraction of water are linear over the entire composition range studied, showing the importance of solvation phenomena. A different straight line of log (kL/s–1)versus XH2O is obtained for each mixture, indicating the influence of other solvent parameters on the reaction rate. A multiparameter regression of G exp with A (acidity vector), B (basicity vector) and GE is used for both reactions; plots of G calc versus G exp are linear with slopes of near unity.  相似文献   

17.
3-Aroyl- and 3-heteroyl-2,4-dihydro-1H-pyrrolo[2,1-c][1,4]benzoxazine-1,2,4-triones react with 3-amino-5,5-dimethyl-2-cyclohexenone to give 3-aroyl-4-hydroxy-1-o-hydroxyphenyl-6,6-dimethyl-2,2,3,4,5,5,6,7-octahydro-1H-indole-3-spiro-2-pyrrole-2,4,5-triones. The structure of the products was proved by X-ray analysis.Translated from Zhurnal Organicheskoi Khimii, Vol. 40, No. 9, 2004, pp. 1405–1409.Original Russian Text Copyright © 2004 by Mashevskaya, Duvalov, Tolmacheva, Aliev, Maslivets.This study was performed under financial support by the Russian Foundation for Basic Research (project nos. 01-03-32641 and 02-03-96411).For communication XLVII, see [1].  相似文献   

18.
Zusammenfassung Arylhydrazon-cyanacetylcarbamidsäureäthylester (I) wurde durch Einwirkung einer Na2CO3-Lösung auf 1-Aryl-5-cyan-6-azauracile (II)1,2 cyclisiert. Nitrile (II) wurden durch Addition von Hydroxylamin in entsprechende Amidoxime (III) übergeführt, welche durch Kochen mit Acetanhydrid die zugehörigen 1-Aryl-5-[5-methyl-1,2,4-oxdiazolyl(3)]-6-azauracile (IV) lieferten.
Aryl hydrazone-cyanoacetylcarbamic acid ethyl esters (I) have been cyclized in Na2CO3 soln. yielding 1-aryl-5-cyano-6-azauraciles (II)1,2. Addition of NH2OH to the nitriles (II) gave the corresponding amidoximes (III), which by refluxing with Ac2O were converted to the corresponding 1-aryl-5-[5-methyl-1, 2, 4-oxdiazolyl(3)]-6-azauraciles (IV).
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19.
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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20.
Competitive demethylation and redox reactions induced by 2,2-diphenyl-3,3-bi-3H-indole-1,1-dioxide,1 (dinitrone) on several nitrogen bearing compounds (pyridines, amides, indoles, hydrazones and amines) are reported.Es wird über kompetitive Demethylierungen und Redoxreaktionen an stickstoffhaltigen Verbindungen (Pyridine, Amide, Indole, Hydrazone und Amine) berichtet, die durch das Dinitron 2,2-Diphenyl-3,3-bi-3H-indol-1,1-dioxid induziert werden.
2,2-Diphenyl-3,3t-bi-3H-indol-1,1t-dioxid: Kompetitive Demethylierung und Redoxreaktionen
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