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1.
5‐Amino‐4‐methyl‐2‐phenyl‐6‐substitutedfuro[2,3‐d]pyrimidines ( 2a‐c ) were reacted with 2,5‐dimethoxytetrahydrfuran to afford the pyrrolyl derivatives 3a‐c . Compound 3a was chosen as intermediate for the synthesis of poly fused heterocycles incorporated furopyrimidines moiety 4–11 . Some of the synthesized compounds were screened for their antibacterial and antifungal activities. 相似文献
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A. L. Lapidus S. D. Pirozhkov A. R. Tumanova T. G. Koksharova N. V. Volkova V. A. Bakulev V. S. Mokrushin 《Russian Chemical Bulletin》1992,41(1):178-180
A new method has been developed for the synthesis of the ethyl ester of the mononitrile of malonic acid by the carbonylation of benzenesulfonyloxyacetonitrile in absolute ethanol in the presence of cobalt carbonyl. The yield of the desired product was 30% with 60–90% conversion of the starting compound. The effects of temperature, pressure, and reaction time were studied.N. D. Zelinskii Institute of Organic Chemistry, Russian Academy of Sciences, 117913 Moscow. S. M. Kirov Urals Polytechnical Institute, Ekaterinburg. Translated from Izvestiya Akademii Nauk, Seriya Khimicheskaya, No. 1, pp. 215–216, January, 1992. 相似文献
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I. Richard Lapidus 《Few-Body Systems》1988,4(2):N29-N29
Few-Body Systems — News Section
Announcement 相似文献5.
Lapidus A. L. Eliseev O. L. Stepin N. N. Bondarenko T. N. 《Russian Chemical Bulletin》2004,53(11):2564-2567
The carboxylation of styrene into carboxylic acids in the N(C4H9)4Br—heptane system in the presence of phosphine complexes and palladium acetate was studied. In the absence of phosphine, the Pd catalyst seems to be stabilized in solution by forming anionic complexes with NBu4Br; the stabilization depends on the acidity of the reaction medium. The catalytic system can be used repeatedly, its activity being reduced only slightly.__________Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 11, pp. 2458–2461, November, 2004. 相似文献
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A. V. Zaitsev G. V. Kozlova V. Yu. Borovkov A. Yu. Krylova A. L. Lapidus V. B. Kazanskii 《Russian Chemical Bulletin》1990,39(11):2394-2396
Diffuse scattering IR spectroscopy was used to study the 10% Co/Al2O3 catalyst for the synthesis of aliphatic hydrocarbons from CO and H2. Ionic and metallic cobalt forms were identified in the IR spectroscopy. The adsorption of CO on these forms is accompanied by the appearance of linear and bridged complexes. After prolonged treatment of the catalyst by a CO + 2H2 mixture, the ions and surface of metallic cobalt remain available for the adsorption of CO. Modification of the surface of metallic cobalt occurs upon the action of the reaction medium. This modification is seen in a bathochromic displacement of the IR bands for the adsorbed and linear CO forms. This displacement is accompanied by a reduction in the strength of the metal-carbon bond in the Coo-CO complex.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 11, pp. 2640–2643, November, 1990. 相似文献
9.
E. Yu. Vol'f T. Yu. Solov'eva M. M. Vartanyan L. Yu. Brezhnev A. L. Lapidus 《Russian Chemical Bulletin》1989,38(11):2356-2358
The synthesis of 3-formyl derivatives of the tetrahydrofuran series was carried out by hydroformylation of 2,3-dihydrofuran and 2,5-dimethoxy-2,5-dihydrofuran in the presence of HRh(CO)(PPh3)3. The influence of the temperature, pressure, catalyst concentration, and the nature of the solvent on the conversion of dihydrofuran, the composition of aldehydes obtained and the selectivity of their formation was investigated.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 11, pp. 2569–2571, November, 1989. 相似文献
10.
Braverman Michael SH.; Stepanov Vladimir D. 《Bulletin London Mathematical Society》1994,26(3):283-287
Necessary and sufficient conditions for the boundedness of thediscrete Hardy operator of the form , from to when 0 < q < 1 <p , is given. 相似文献