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41.
Franco Piacenti Mario Bianchi Piero Frediani Ugo Matteoli 《Journal of organometallic chemistry》1975,87(3):C54-C55
Both normal and secondary alkylcobalt carbonyls are shown not to undergo isomerization under catalytic “oxo” conditions, and the relevance of this obervation for the mechanism of the “oxo” reaction is discussed. 相似文献
42.
Topochemical investigations of peptide systems 总被引:4,自引:0,他引:4
M M Shemyakin Y A Ovchinnikov V T Ivanov 《Angewandte Chemie (International ed. in English)》1969,8(7):492-499
The basic principles of the topochemical approach to the investigation of the structure-function relation in peptide systems are formulated. This approach makes use of the new possibility of transforming natural peptides, consisting in the modification of the molecule as a whole and utilization of the resultant analogs to elucidate the boundaries of the stereoelectronic complementarity of the biologically active peptide to the corresponding receptor. In particular, on the example of depsipeptide antibiotics and their topochemical analogs the fruitfulness of using such compounds as tools in elucidating the physicochemical basis of functioning of biological membranes is shown. The topochemical principle has also been applied in preparing specific competitive inhibitors of proteolytic enzymes, whose study may shed light on the nature of the forces binding the substrate to the contact site of the corresponding enzyme. 相似文献
43.
G. B. Golubitskii E. V. Budko E. M. Basova A. V. Kostarnoi V. M. Ivanov 《Journal of Analytical Chemistry》2007,62(2):152-156
The effects of acetonitrile and potassium dihydrogen phosphate concentrations in a mobile phase and the pH of the mobile phase on the retention of analgin (dipyrone) and anesthesin (benzocaine) on Symmetry C18 and Nova-Pak CN HP sorbents with grafted octadecylsilanol and nitrile groups, respectively, were studied. It was found that, under identical conditions, retention on the sorbent with grafted nitrile groups was weaker. A rapid and cost-effective procedure was developed for the determination of analgin and anesthesin in the analysis of Bellalgin tablets. 相似文献
44.
G. B. Golubitskii E. V. Budko E. M. Basova V. M. Ivanov 《Journal of Analytical Chemistry》2007,62(7):658-664
4-Methylaminoantipyrine (4-MAAP) is the main product of analgin decomposition in aqueous-organic solutions used in the analysis of Pentalgin N and Pentalgin FS tablets. The determination of 4-MAAP in tablets is complicated by the fast decomposition of analgin in the course of sample dissolution. The use of nonaqueous solvents in subsequent HPLC analysis is unreasonable, because the shapes of analyte peaks are deteriorated and the decomposition of analgin is not prevented. A procedure for the kinetic-chromatographic determination of both 4-MAAP in tablets and its amount at the moment of sample dissolution is proposed. 相似文献
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R. F. Bakeeva L. Yu. Tartykova L. A. Kudryavtseva V. E. Bel'skii N. V. Usol'tseva B. E. Ivanov 《Russian Chemical Bulletin》1992,41(5):817-821
The kinetics of decomposition of p-nitrophenyldimethyl thiophosphate (1) were investigated spectrophotometrically in the n-decylammonium chloride-n-decylamine-water system (DAC-DA-H2O), in which micellar or lamellar liquid-crystalline phases are formed as a function of the concentration of components. It was shown that1 is dealkylated in both phases. An increase in the surface charge density of associates decreases the rate of dealkylation. The activation energy in the lamellar phase is significantly higher than in the micellar phase.A. E. Arbuzov Institute of Organic and Physical Chemistry, Kazan' Scientific Center, Russian Academy of Sciences, 420083 Kazan'. Translated from Izvestiya Akademii Nauk, Seriya Khimicheskaya, No. 5, pp. 1042–1048, May, 1992. 相似文献
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