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排序方式: 共有254条查询结果,搜索用时 15 毫秒
81.
A general method for the synthesis of various N,N-disubstituted cyanoacetamides from readily available methyl malonyl chloride and secondary amines, including sterically demanding aliphatic and aromatic amines, is described. 相似文献
82.
Barbara Milczarska Henryk Foks Zofia Zwolska 《Phosphorus, sulfur, and silicon and the related elements》2013,188(10):2255-2264
The reactivity of the chloride atom of 2-cyano-6-chloropyrazine was used in the reactions with amines, 1,2,3,4-tetrahydroisoquinoline and 1,3,3-trimethyl-6-azabicyclo-[3,2,1]-octane, which yielded the substrates for the syntheses of a series of new derivatives. The bulk of them were tested for their tuberculostatic activity. MIC values of the most active ones ( 2a , b , 5b , 7a , 9b , and 11b ) were within 3.1–50 μ g/mL. 相似文献
83.
Henryk Foks Danuta Pancechowska-Ksepko Mieczysław Janowiec Zofia Zwolska Ewa Augustynowicz-Kopeé 《Phosphorus, sulfur, and silicon and the related elements》2013,188(10):2291-2297
1,1-bis-methylthio-2-nitro-ethene was used as a substrate to the syntheses of new heterocyclic compounds. In the reactions, with 1-phenylpiperazine—the corresponding diaminonitroethane 1 , 1,3-diaminonitropropane, and 1,3-diaminonitropropanol—the nitromethylenotetrahydropyrimidine derivatives 2 and 3 were prepared, whereas, with o-phenylenediamine—2-nitromethyleno-benzimidazole 4 were obtained. In the condensation reactions of compounds 2 , 3 , and 4 with benzoyl isothiocyanate, the products 5 , 6 , and 7 were obtained, and afterwards two of them, 5 and 6 , were transformed into the isothiazolines 8 and 9 . 1,1-bis-(4-phenylpiperazino)-2-nitroethane ( 1 ) was exposed to the action of phenyl isothiocyanate and the derivative obtained ( 10 ) was transformed, in the reaction with phenacylbromide, in to benzoylonitrothiophene 11 . The diazo compounds 12 , 13 , and 14 were obtained in the reactions of nitromethylenotetrahydropyrimidines 2 and 3 and of 2-nitromethylenobenzimidazole 4 with benzenediazonium chloride. The derivatives obtained were tested in vitro for their tuberculostatic activity. The compounds 7 (MIC 8–32 μg/mL) and 14 (MIC 16–63 μg/mL) appeared to be the most active compounds. 相似文献
84.
L. Bukowski Zofia Zwolska Ewa Augustynowicz-Kopeć 《Phosphorus, sulfur, and silicon and the related elements》2013,188(7):879-887
Abstract The reactions of 2-cyanomethyl-1-methyl-1H-imidazo[4,5-b]pyridine with isothiocyanates, nitroso compounds, acid chlorides, and thioglycolic acid were investigated. New imidazo[4,5-b]pyridine derivatives with various substituents in 2-position and derivatives of the new pyrrolo[2′,1′:2,3]imidazo[4,5-b]pyridine ring system were synthesized. The compounds obtained were tested in vitro for their tuberculostatic activity. 相似文献
85.
Anna Michnik Kinga Polaczek-Grelik Piotr Leśniak Zofia Drzazga 《Journal of Thermal Analysis and Calorimetry》2013,111(3):1845-1852
An attempt has been made to detect the effect of a small dose of ionizing radiation on the course of α,β-globulin thermal denaturation in aqueous solutions. Doses of 0.1 and 1.8 Gy have been delivered using γ-rays emitted by 60Co isotope while doses of 10 and 100 Gy have been supplied by X-rays produced by linear accelerator. The highest dose has visibly changed DSC curve of protein solution while the changes due to lower doses are hardly detectable. Although very weak, the irradiation effect found has been dose dependent. The results suggest that the influence of ionizing radiation on globulins solution is bigger when the dose rate is lower at given dose. The opposite direction of differences between irradiated and control samples for fresh and stored protein solutions suggests various characters of changes in initial and later period of sample aging. This may be an important reason for difficulties in an investigation of the effect of ionizing radiation on protein solution, especially for low doses delivered very slowly. 相似文献
86.
Katarzyna Gobis Henryk Foks Zofia Zwolska Ewa Augustynowicz-Kopeć 《Phosphorus, sulfur, and silicon and the related elements》2013,188(5):965-975
Methyldithiocarbonyl derivative 2 of pyrazine-2-carboxylic acid N′-methyl-hydrazide 1 was synthesized by methylation of CS2 adduct. Benzylamine caused the decomposition of compound 2 to pyrazine-2-carboxylic acid benzylamide 5 and 1,3-dibenzylthiourea 6. N-methyl-N′-(pyrazine-2-carbonyl)-hydrazinecarbodithioic acid methyl ester 2 were evidenced to cyclize to 3-methyl-5-pyrazin-2-yl-3H-[1, 3, 4]oxadiazole-2-thione 8 in the presence of triethylamine. In the reactions with secondary amines such as morpholine, pyrrolidine and phenylpiperazine pyrazinoyl derivatives (9–11) of thiosemicarbazide were obtained. Hydrazine, methylhydrazine, aminoalcohols, and N-alkylamino-substituted cyclic amines reacted with cyclization to 4-substituted 1,2,4-triazole-3-thiones 12, 13, and 18–22. Synthesized compounds exhibited low tuberculostatic activity in vitro (MIC 50–100 μg/mL). 相似文献
87.
Wawrzyniec Podkoscielny Wanda Kowalewska 《Journal of polymer science. Part A, Polymer chemistry》1984,22(5):1025-1033
Several polythioesters by interfacial polycondensation of 1,4-di(mercaptomethyl)-2,3,5,6-tetramethylbenzene with oxalyl, succinyl, adipoyl, suberoyl, and sebacoyl chlorides were obtained. To determine the optimal conditions for interfacial polycondensation, the influence of the following factors on yield and value of reduced viscosity were studied: type of organic phase, concentration of hydrogen chloride acceptor, the quantitative ratio of aqueous to organic phase, molar ratio of reagents; temperature of reaction, rate of acid chloride addition, and contribution of catalyst. Thorough studies were carried out only for polycondensation of the dithiol with adipoyl and sebacoyl chlorides. The structure of all polythioesters obtained under the model conditions was determined by elementary analysis and infrared spectra. Initial decomposition temperature, mass loss in percentage at the same temperature, maximum rate of decomposition, and mass loss percentage at 100–400°C were defined by thermogravimetric analyses. Chemical resistance of the polythioesters was determined by treatment with some organic solvents, mineral acids (concentrated and 10%), and sodium hydroxide (10 and 50%). Some mechanical and electrical properties of the polythioesters obtained from dithiol and adipoyl and sebacoyl chlorides were determined. The molecular weight was not measured because of the low solubility of the polythioesters. 相似文献
88.
Tomasz Bauer Christian Chapuis Jaroslaw Kiegiel Janusz W. Krajewski Katarzyna Piechota Zofia Urbanczyk-Lipkowska Janusz Jurczak 《Helvetica chimica acta》1996,79(4):1059-1066
An efficient synthesis of the two title compounds is reported, as well as their X-ray crystal-structure analyses. A discussion based on stereoelectronic considerations rationalizes the first example of a crystalline SO2/C(O) syn-periplanar conformer of a N-acylbornane-10,2-sultam. 相似文献
89.
The N2 reduction reaction in the system (η-C5H5)2TiCl2-Mg in tetrahydrofuran was examined. The 13C and 1H NMR results as well as the chemical properties of the products formed revealed that the reaction yielded a mixture of compounds in which the titanium atom was bonded both to the μ-(η5: η5-fulvalene) ligand and to the cyclopentadienyl ligands. In this system dinitrogen undergoes reduction to N3?, which then forms M3N bridges (M = Ti, Mg). The nitride nitrogen may readily be oxidized to imide nitride N?1, which may react further, e.g. with carbon monoxide to produce isocyanates, or, with excess oxidizing agent N2. THF in this system undergoes polymerisation. In addition, a ?OC4H9 alkoxy group is formed which makes the substitution of the cyclopentadienyl group bonded to the titanium atoms possible. 相似文献
90.
A new synthesis has been described for coloured dihydrofurylium salts of the hemicyanine type based on the reaction of 2,2,5-trisubstituted 3-benzoyl-methylidene-2,3-dihydrofurans with organomagnesium or organolithium compounds, tertiary aromatic amines or 1,1-diarylethylenes.
Eine neue Synthese von DihydrofuryliumfarbsalzenVorläufige Mitteilung
Zusammenfassung Es wurde eine neue Synthese für Dihydrofuryliumfarbsalze beschrieben. Die Synthese gründet sich auf die Reaktion von 2,2,5-trisubstituierten 3-Benzoylmethyliden-2,3-dihydrofuranen mit den Magnesium- bzw. Lithiumorganischen Verbindungen, tertiären aromatischen Aminen oder unsymmetrischen Diarylethylenen.相似文献