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1.
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   

2.
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   

3.
Reduction of 1-alkyl-3-(2-quinolyl)quinolinium halides with sodium borohydride leads to 1-alkyl-1,2-dihydro-2,3-biquinolyls which, except for the ethoxycarbonyl derivative, undergo rearrangement to 1-alkyl-1,4-dihydro-2,3-biquinolyls. The last can be synthesized by the alkylation of the corresponding 1,4-dihydro-2,3-biquinolyls under conditions of interphase catalysis and in the system KOH-DMSO.For Communication 7, see [1].Stavropol' State University, Stavropol' 355009, Russia; nauka@stavsu.ru. Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 8, pp. 1084–1087, August, 2000.  相似文献   

4.
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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5.
    
A universal key component is proposed for the preparation of oligonucleotides with 3- and 5-terminal phosphate groups — 2,3-dibenzoyluridin-5-yl (4-chlorophenylphosphate) (pU(Bz)2), which is a potential source of the phosphate group. The condensation ofpU(Bz)2 with the 5-OH or the 3-OH group of a protected oligonucleotide leads to the formation of oligodeoxyribonucleotides with 5- or 3-terminal uridine, respectively. The oxidation of the 2,3-cis-glycol group of the terminal uridine unit followed by -elimination forms oligodeoxyribonucleotides with terminal phosphate groups.M. V. Lomonosov Moscow State University. Translated from Khimiya Prirodnykh Soedinenii, No. 5, pp. 731–734, September–October, 1987.  相似文献   

6.
Summary Complexes of general formula MLmCl2 · nH2O, where M=cobalt(II) or nickel(II); L=2-(4-methyl, 2-pyridyl)-benzimidazole (mpbi), 2-(4-methyl, 2-pyridyl)benzothiazole (mpbt), 2-(4-methyl, 2-pyridyl)benzoxazole (mpbo), 2-(4-methyl, 2-quinolyl)benzoxazole (mqbo), or 2-(4-methyl, 8-quinolyl)benzoxazole (mqbo); m=1,2; n=0–3, were prepared and characterized by t.g.a., conductance and magnetic measurements, i.r. and diffuse-reflectance electronic spectra.All the ligands behave as bidentate and coordinate through the pyridine- and isoxazole-nitrogen atoms.The nickel complexes have distorted octahedral or fivecoordinate structures. The cobalt complexes arepseudo-tet- rahedral except Co(mpbo)2Cl2·2H2O where the metal is six-coordinate.  相似文献   

7.
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   

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.
The reaction of 3-epoxypropionyl-2-pyrazolines and 3(5)-epoxypropionylpyrazoles with hydrazine hydrate leads to 4,5,4,5-tetrahydro- and -4,5-dihydro-3,3-di-pyrazolyls, on the basis of which 4,5-dihydro-3,3-dipyrazolyls and 3,3-dipyrazolyls were subsequently obtained.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 2, pp. 226–229, February, 1984.  相似文献   

10.
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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11.
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   

12.
Ru2II(ttha)(H2O)2]2– (ttha6–= triethylene tetramine hexa-acetate), prepared by the reduction of the ruthenium(III) precursor, reacts with 2,2-bipyridine (2,2-bpy) in a multi-step fashion. The first 2,2-bpy equivalent (1:1) adds with bidentate chelation at one ruthenium(II) site as revealed by separate ruthenium(II)/(III) waves at 0.03 and 0.54V vs. n.h.e. A second equivalent of 2,2-bpy (1:2) is initially stored and retained as the [Zn(2,2-bpy)]2+ complex. Further addition of 2,2-bpy initiates coordination at the second ruthenium(II) site. [Ru2(ttha)-(2,2-bpy)(H2O)]2– forms a strong ion-pair with zinc(II) that is in rapid equilibrium with the Zn(H2O)62+/Zn(2,2-bpy)]2+ pool. The solubility of the ion-pair is low. The ion-pair exhibits a shifted ruthenium(II)/(III) wave at 0.60V. Higher amounts of 2,2-bpy recomplex the zinc(II), solubilizing the complex and returning the E1/2 value to 0.54V. Other ligands which either have a higher affinity for ruthenium(II) centres than for zinc(II) as bidentate donors (1,10-phenanthroline), or ligands that cannot form bidentate zinc(II) complexes [(2-methylpyrazine, 4,4-bipyridine (4,4-bpy), and 2,3-bipyridine (2,3-bpy)] do not exhibit the unusual competition by zinc(II). These ligands all add statistically to the ruthenium(II) centres forming 1:2 complexes with 1:2 stoichiometries. 1H-n.m.r. studies of the Ru(II)polyaminopolycarboxylate complexes [RuII(hedta)(H2O)]– complex, and [Ru2(ttha)(H2O)2]2– itself, reveal that substitution of 2,3-bpy at ruthenium(II) sites occurs with an initial kinetic split between the pyridyl rings of the 3- less-hindered and 2-more-hindered ring. A slower rearrangement occurs, producing the isomer of the more-hindered 2-substituted ring. A process is driven by forming a more -accepting system when ruthenium(II) binds to the 2-ring of 2,3-bpy. Understanding the unusual influence of zinc(II) on the substitution of 2,2-bpy with [Ru2(ttha)(H2O)2]2– clarifies the nature of the 1:1 complex – namely that the 2,2-bpy becomes bidentate at one ruthenium(II) centre rather than serving as a trans-bridging ligand between both ruthenium(II) centres within one [Ru2(ttha)]2– unit.  相似文献   

13.
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   

14.
Zusammenfassung Methylierung von o-Aminothiophenol lieferte o-Methylmercapto-anilin, dessen Tosylat zur Herstellung des Tosylates der N-(o-Methylmercaptophenyl)--aminopropionsäure verwendet wurde. Cyclisierung von -(2-Methylmercaptodiphenyl)-aminopropionsäure ergab 1-(2-Methylmercaptophenyl)-4-oxo-1,2,3,4-tetrahydrochinolin, dessen Oxim zu 1-(2-Methylmercaptophenyl)-4-amino-1,2,3,4-tetrahydrochinolin reduziert wurde. N-[-(4-Methylpiperazinyl-1)-propyl]-2-methylthiodiphenylamin wurde durch Direktsubstitution van 2-Methylthio-diphenylamin erhalten.
Methylation of o-aminothiophenol gave o-methyl-mercaptoaniline, the tosylate of which was used for the preparation of N-(o-methylmercaptophenyl)--aminopropionic acid tosylate. Cyclization of -(2-methylmercapto-diphenyl)-aminopropionic acid yielded 1-(2-methylmercaptophenyl)-4-oxo-1,2,3,4-tetrahydroquinoline, the oxime of which was reduced to 1-(2-methylmercaptophenyl)-4-amino-1,2,3,4-tetrahydroquinoline. N-[-(4-Methylpiperazino-1)-propyl]-2-methylmercapto-diphenylamine was prepared by direct su stitution of 2-methylmercapto-diphenylamine.
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15.
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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16.
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   

17.
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   

18.
-Diimines, RN:C(R)C(R):NR(LL) derived from glyoxal, GLL (R=H) abbreviated as GAA (R= R=4-dimethylaminophenyl) or GHA (R= R=4-hydroxyphenyl), and derived from biacetyl, BLL (R=Me) abbreviated as BDH (R=R= NH2), BOH (R=NH2, R=OH) react with carbonylrhodium(I) compounds to give different products depending on the imino substituents in the ligand and/or the solvent employed. The reaction of -diimines bearing amino groups, such as GAA or BDH with [RhCl(CO)2]2 in acetone yields binuclear [RhCl(CO)2]2(-LL) while in CH2Cl2 ionic [Rh- (CO)2(LL)]+[RhCl2(CO)2] species are obtained. In acetone [RhCl(CO)2]2(-GAA) exists as an equilibrium mixture between two different neutral binuclear species; [Rh(CO)2(BDH)]+ exists as a mixture of two species containing chelate or monodentate bonded diimine respectively. GAA or BDH react in situ with [RhCl(CO)(C2H4)]2 in benzene to yield tetracoordinated monocarbonylated [RhCl(CO)(LL)] compounds. -Diimines (LL) bearing hydroxy groups, such as GHA or BOH react with [RhCl(CO)2]2 or [RhCl(CO)(C2H4)]2 to give pentacoordinated dicarbonylated [RhCl(CO)2(LL)] compounds.  相似文献   

19.
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   

20.
Zusammenfassung Die Absorptionsspektren folgender Verbindungen: Chinoxalin, 2,2-Dichinoxalyl, 2-Methylchinoxalin, 3,3-Dimethyl-2,2-dichinoxalyl, Pyrazin, 2,2-Dipyrazyl, 2-Methylpyrazin und 5,5-Dimethyl-2,2dipyrazyl wurden in Methanol im Bereich von 225–360 nm bestimmt.Eine Methode zur quantitativen Bestimmung der genannten Verbindungen wurde ausgearbeitet, um den Herstellungsprozeß von 2,2Dichinoxalyl, 3,3-Dimethyl-2,2-dichinoxalyl, 2,2-Dipyrazyl und 5,5-Dimethyl-2,2-dipyrazyl aus den entsprechenden Monomeren durch direkte Photometrierung von Proben der Reaktionsgemische, die in einem beliebigen Stadium der Synthese dem Reaktor entnommen wurden, verfolgen zu können.
Spectrophotometric determination of dehydrocondensation products of pyrazines and quinoxalines
Summary The absorption spectra of the following compounds: quinoxaline, 2,2-diquinoxalyl, 2-methylquinoxaline, 3,3-dimethyl-2-2-diquinoxalyl, pyrazine, 2,2-dipyrazyl, 2-methylpyrazine and 5,5-dimethyl-2,2-dipyrazyl were determined in methanol in the region of 225–360 nm. A method was developed for the quantitative determination of these compounds in order to be able to follow the preparation methods of 2,2-diquinoxalyl, 3,3-dimethyl-2,2-diquinoxalyl, 2,2-dipyrazyl and 5,5-dimethyl-2,2-dipyrazyl from the corresponding monomers through direct photometration of samples of the reaction mixture, which can be taken from the reactor at a selected stage of the synthesis.
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