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1.
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
2.
A. V. Aksenov I. V. Aksenova I. V. Borovlev Yu. I. Smushkevich 《Chemistry of Heterocyclic Compounds》1997,33(8):954-958
The 2,3-biquinolyl dianion, when reacting with aryl- and hetaryl halides, forms arylation products at the 4 position, and treatment of these products with alkyl halides or water yields 1-alkyl-4-aryl-1,4-dihydro-2,3-biquinolyls or 4-aryl-1,4-dihydro-2,3-biquinolyls, respectively. Oxidation of the latter yields 4-aryl-2,3-biquinolyls. The cation dependence of the arylation reaction is demonstrated.Stavropol' State University, Stavropol' 355009. Russian Chemical Engineering University, Moscow 125190. Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 8, pp. 1094–1099, August, 1997. 相似文献
3.
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
4.
V. M. Kopelevich L. N. Bulanova Yu. V. Belousova A. V. Lysenkova V. F. Pozdnev V. I. Gunar 《Chemistry of Natural Compounds》1988,23(4):493-495
The synthesis has been performed of dephosphocoenzyme A, 4,4-di-0-(2,3-9-isopropylideneadenosineuronyl)pantethine, and of 4,4-di(2,3-isopropylideneadenosineuronylamino)-4,4-dideoxypantethine from 2,3-0-isopropylidene adenosineuronic acid, using as condensing agents the tert-butyl dicarbonatepyridine and the N,N-dicyclohexylcarbodiimide-N-hydroxysuccinimide systems, respectively.Vitaminy Scientific-Production Amalgamation, Moscow. Translated from Khimiya Prirodnykh Soedinenii, No. 4, pp. 587–590, July–August, 1987. 相似文献
5.
N. S. Prostakov Ishmael Rafael Vaskes N. M. Mikhailova V. P. Zvolinskii V. F. Zakharov M. A. Galiullin 《Chemistry of Heterocyclic Compounds》1978,14(8):875-878
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
6.
The acylation of 4-(3,4-dimethoxyphenyl)benzo-15-crown-5 by carboxylic acid anhydrides in the presence of equimolar amounts of perchloric acid gave 1-alkyl-3-[3,4-(3,6,9,12,15-pentaoxa-1, 2-cyclopentadeceno)phenyl]-6,7-dimethoxybenzo[c]pyrilium salts, which are converted by the action of ammonia to the corresponding isoquinolines.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 2, pp. 171–172, February, 1989. 相似文献
7.
L. G. Avramenko Yu. E. Sklyar M. E. Perel'son M. G. Pimenov 《Chemistry of Natural Compounds》1975,9(1):15-16
Summary From the roots ofPilopleura kozo-poljanskii Schischk. a new chromone has been isolated which has been called pilopleurin. On the basis of the results of hydrolysis and UV, IR, and NMR spectroscopy, it has been established that pilopleurin has the structure 5-hydroxy-2,2,2-trimethyl-3-senecioyloxy-3,4-dihydropyrano-5,6:6,7-chromone.Pyatigorsk Pharmaceutical Institute. Translated from Khimiya Prirodnykh Soedinenii, No. 1, pp. 18–20, January–February, 1973. 相似文献
8.
I. N. Azerbaev T. G. Sarbaev N. A. Gogol K. B. Erzhanov 《Chemistry of Heterocyclic Compounds》1968,4(3):363-365
The kinetics of the hydrogenation of the and isomers of 1,4-bis(4-hydroxy-1, 2, 5-trimethyl-4-piperidyl)-1, 3-butadiyne in methanol and ethanol on the catalysts Raney nickel, platinized carbon, and palladium on supports has been studied. It has been shown that the rates of hydrogenation of the and isomers differ on all the catalysts. In the presence of platinum and nickel, hydrogenation takes place as far as the saturated compound, and in the presence of palladium to the diene. 相似文献
9.
M. E. Perel'son V. V. Bandyshev Yu. E. Sklyar K. Vezhkhovska-Renke N. V. Veselovskaya M. G. Pimenov 《Chemistry of Natural Compounds》1977,12(5):533-537
Summary Two new terpenoid coumarins — tadzhiferin (I) and tadzhikorin (II) — have been isolated from the fruit ofFerula tadshikorum M. Pimen.On the basis of physicochemical and spectral investigations, the structure of 7-(9-hydroxy-3,7,11-trimethyldodeca-2,6,10-trienyloxy)coumarin is proposed for (I) and that of 7-(4-acetoxy-9-hydroxy-3,7,11-trimethyldodeca-2,6,10-trienyloxy)coumarin for (II).All-Union Scientific-Research Institute of Medicinal Plants, Moscow. M. V. Lomonosov State University. Botanical Garden, Moscow. Translated from Khimiya Prirodnykh Soedinenii, No. 5, pp. 593–599, September–October, 1976. 相似文献
10.
John P. Acton Dorothy J. Donnelly John A. Donnelly 《Monatshefte für Chemie / Chemical Monthly》1982,113(1):73-79
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.相似文献
11.
S. Narayanan B. Prabhu Prasad V. Vishwanathan 《Reaction Kinetics and Catalysis Letters》1992,48(2):497-503
Aniline alkylation activity of simple oxides and supported vanadia oxides are compared from the point of view of acidity and vanadia-support interaction.
IICT communication No. 2915 相似文献
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IICT communication No. 2915 相似文献
12.
Conclusions The methylation of steroido[16,17-d]-4H-1,2'-oxazoles with methyl fluosulfonate leads to N-methyl-3-hydroxysteroido[16,17-d]tetrahydro-1,2-oxazoles, which when treated with POC13 are converted to steroidal 16-(2-glyoxyl)17-lactones.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 8, pp. 1924–1926, August, 1977. 相似文献
13.
L. T. Eremenko L. O. Atovmyan N. I. Golovina G. V. Oreshko M. A. Fadeev 《Russian Chemical Bulletin》1987,36(9):1870-1872
Conclusions The product of conversion of O-bis(2-fluoro-2,2-dinitroethyl)nitromethylbis(2-fluoro-2,2-dinitroethyl)carboxime in methanol or ether is O-bis(2-fluoro-2,2-dinitroethyl)nitromethyl-2-fluoro-2,2-dinitroethyl-2'-fluoro-2-nitroethylenecarboxinie, the structure of which has been established by x-ray diffraction analysis.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 9, pp. 2019–2021, September, 1987. 相似文献
14.
A. A. Savina M. E. Perel'son G. K. Nikonov A. I. Ban'kovskii 《Chemistry of Natural Compounds》1973,6(5):536-539
Conclusions A new coumarin has been isolated from the roots ofSeseli sessiliflorum for which the structure of 3-angeloyloxy-2,2-dimethyl-4-(trans-3-methylthioacryloyloxy)-3, 4-dihydropyrano-5,6:8,7-coumarin has been proposed. This is the first time that esters of 3-methylthioacrylic acid have been found in the coumarin series.All-Union Scientific-Research Institute of Medicinal Plants. Translated from Khimiya Prirodnykh Soedinenii, No. 5, pp. 517–521, September–October, 1970. 相似文献
15.
H. Steinwandter 《Fresenius' Journal of Analytical Chemistry》1982,312(4):342-345
Summary An on-line method for the extraction and isolation of pesticides in milk and dairy products is discussed. Milk and aqueous dairy products are homogenized with silica gel. This sample having a water content of approximately 40% is brought into a column, which is filled with the 10% water silica gel necessary for the clean-up. Extraction and clean-up of the pesticides occurs on-line with light petroleum — dichloromethane 80+20 (v/v). The pesticides move with the solvent front from the upper silica gel to the lower 10% water column, where they are cleaned up. Quantitative identification of the pesticides is performed by glass capillary gas chromatography (ECD) as well as by mass spectroscopy. HCB, -HCH, -HCH, -HCH, -Heptachloroepoxide, p,p-DDE, Dieldrin, o,p-DDT, p,p-DDT, 2,4,5,2,4,5-Hexachlorobiphenyl and 2,3,4,2,4,5-Hexachlorobiphenyl were identified in milkThe hexachlorobiphenyl concentrations in milk are about 20 times the value of o,p-DDT and p,p-DDT.
Part II: see [2] 相似文献
Beiträge zur Verwendung von Kieselgel in der PesticidanalytikIII. On-Line-Verfahren zur Extraktion und zur Isolierung von Chlorkohlenwasserstoff-Pesticiden und polychlorierten Biphenylen aus Milch und Molkereiprodukten
Zusammenfassung Eine on-line-Methode zur Extraktion und Isolierung der Chlorkohlenwasserstoff-Pesticide in Milch und Milchprodukten wird beschrieben. Milch und wäßrige Milchprodukte werden zuerst mit Kieselgel homogenisiert. Diese Probenhomogenisate mit einem Wassergehalt von etwa 40% werden anschließend in eine Chromatographiesäule gefüllt, in der sich bereits das für den clean-up erforderliche Kieselgel mit 10% Wasserbelegung befindet. Die Extraktion bzw. der clean-up der Pesticide erfolgt on-line mit Petrolether-Dichlormethan 80+20 (v/v). Die Pesticide werden in der Lösungsmittelfront von der oberen auf die untere Kieselgelsäule (10% Wassergehalt) transportiert, an welcher schließlich die Abtrennung der Pesticide von den Störkomponenten erfolgt. Die Identifizierung und Quantifizierung der Pesticide erfolgt sowohl gas-chromatographisch (ECD) an Capillarsäulen als auch massenspektrometrisch. HCB, -HCH, -HCH, -HCH, -Heptachlorepoxid, p,p-DDE, Dieldrin, o,p-DDT, p,p-DDT, 2,4,5,2,4,5-Hexachlorbiphenyl und 2,3,4,2,4,5-Hexachlorbiphenyl wurden in der Milch gefunden. Die Gehalte der beiden Hexachlorbiphenylkomponenten sind etwa 20mal so groß wie die von o,p-DDT und p,p-DDT.
Part II: see [2] 相似文献
16.
N. F. Gashimov A. Z. Abyshev A. A. Kagramanov L. I. Bozhkova 《Chemistry of Natural Compounds》1979,15(1):11-13
Summary 7-(3,3-Dimethylallyloxy)-6-methoxycoumarin and two new coumarins — ramosin and ramosinin — have been isolated from the epigeal part ofHaplophyllum ramosissimum.On the basis of IR, PMR, and mass spectroscopy and chemical reactions, the structure of 8-(3,3-dimethylallyl)-7-(3,3-dimethylallyloxy)coumarin (II) has been proposed for ramosin and that of 3-(1,1-dimethylallyl)-8-(3,3-dimethylallyl)-7-methoxycoumarin (III) for ramosinin.Leningrad Sanitary-Hygienic Medical Institute. Institute of Chemistry, Academy of Sciences of the Turkmen SSR, Ashkhabad. Translated from Khimiya Prirodnykh Soedinenii, No. 1, pp. 15–17, January–February, 1979. 相似文献
17.
Zusammenfassung Der Halogenaustausch zwischen festem AgCl und einer Reihe von flüssigen Organosulfenylchloriden des Typs RRRCSCl (R, R, R=F, Cl, CF3, CF3S) wurde mit Hilfe von radioaktivem36Cl untersucht. Die Ergebnisse deuten darauf hin, daß stark elektronegative Substituenten R, R und R eine Polarisierung der S–Cl-Bindung in den Sulfenylchloriden induzieren und dadurch die heterolytische Reaktivität dieser Bindung erhöhen.
Mit 3 Abbildungen
12. Mitt. vgl.A. Haas undH. Reinke, Chem. Ber.102, 2718 (1969). 相似文献
Heterogeneous36 Cl exchange between halogenated organosulphenyl chlorides and silver chloride
The halogen exchange between solid AgCl and a number of liquid organosulphenyl chlorides of the type RRRCSCl (R, R, R=F, Cl, CF3, CF3S) has been studied using36Cl as a tracer. On the basis of the results it is suggested that highly electronegative substituents R, R and R, by polarizing the S–Cl bonds in the sulphenyl chlorides, favour the heterolytic reactivity of these bonds.
Mit 3 Abbildungen
12. Mitt. vgl.A. Haas undH. Reinke, Chem. Ber.102, 2718 (1969). 相似文献
18.
Alkylation of 3-thiocarbamoyl-3,4,5,6-tetrahydropyridine-2(1H)-one with methyl iodide has given 5-methylthio-2,6-diazabicyclo[2.2.2]oct-5-en-3-one and 3-methyl-thiocarbonyl-3,4-dihydropyridine-2(1H)-one. Alkylation of 3-thiocarbamoyl-3,4-dihydridine-2(1H)-one with iodoacetamide affords 3-(1-amino-1-carbamoyl-3,4-methyl-thiomethylene)-1,4-dihydropyridine-2-one, which in acidic media is converted into 3-(4-oxo-3,5-dihydro-1,3-thiazol-2-ylidene)-1,4-dihydropyridine-2-one.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 6, pp. 787–794, June, 1989. 相似文献
19.
A. A. Ziyaev O. S. Otroshchenko A. S. Sadykov G. A. Tolkacheva 《Chemistry of Heterocyclic Compounds》1969,5(2):276-276
In a study of the dimerization of N-methylanabasine in the presence of metallic sodium under conditions for the dimerization of pyridine, it was found that the reaction does not take place at room temperature while at 50–70° C it leads to the formation of,-di(1-methylpiperid-2-yl)-,-bipyridyl. Oxidation of the latter yielded 4,4-bipyridyl-5, 5-dicarboxylic acid, the decarboxylation of which gave,-bipyridyl. 相似文献
20.
4-Aminobenzo[1,2-b]-1,4-diazabicyclo[2.2.2]octene and 4-aminodibenzo[1,2-b, e]-1,4-diazabicyclo[2.2.2]octadiene have been prepared by cyclization reactions of N--chloroethyl derivatives of 1,2,4-triaminobenzene and aminophenazine, and subsequent catalytic hydrogenation of the corresponding 4-nitrobenzo[1,2-b]-1,4-diazabicyclo[2.2.2]octene and 4-benzylaminodibenzo[1,2-b,e]-1,4-diazabicyclo[2.2.2]-octadiene. Using the conversion of these compounds to azides as an example, we have demonstrated the feasibility of applying these primary aromatic amines for the synthesis of derivatives of these heterocycles.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 6, pp. 831–837, June, 1988. 相似文献