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951.
952.
A. N. Kost L. N. Khaimov Yu. Dzhurakulov K. Kh. Khaidarov L. D. Lebedeva A. L. Kotov 《Chemistry of Heterocyclic Compounds》1975,11(11):1263-1266
2-Substituted or 2,2-disubstituted 4,6-dioxo-1,3-dioxanes, which are analogs of Meldrum's acid and were obtained by reaction of malonic acid with acetic anhydride and the appropriate carbonyl compound in the presence of sulfuric acid, exist in solution preferably in a single form according to the PMR and 13C NMR spectral data. Fluctuation of the CH2 group is not observed. The mass spectra are characteristic and are distinguished by splitting out of the carbonyl compound from the molecular ion or successive splitting out of CO2 and ketene molecules. The Meldrum acid analogs do not affect plant growth but have a depressive effect on the central nervous system of animals and low toxicity.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 11, pp. 1482–1486, November, 1975. 相似文献
953.
954.
955.
E. S. Domnina G. G. Skvortsova N. P. Glazkova M. F. Shostakovskii 《Chemistry of Heterocyclic Compounds》1967,2(3):283-286
The reaction of indole with acetylene under pressure is investigated. It is shown that under the action of KOH in aqueous dioxane at 220° C, N-vinylindole C10H9N is formed in 66% yield, and that this compound undergoes free radical and cationic polymerization. 相似文献
956.
L. N. Ivanova T. A. Severina G. A. Kogan V. F. Kucherov 《Russian Chemical Bulletin》1966,15(7):1167-1170
Conclusions The reactions of hexahydro-1,3-indandlone with ammonia and some amines were studied, and the structures of the products formed were proved. In the alkylation of-diketones of the hexahydroindan series and their enamines under the usual conditions C-alkylation products are not formed.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 7, pp. 1214–1218, July, 1966. 相似文献
957.
958.
Modern activation analysis requires the application of efficient data processing for the evaluation of theγ-spectra of samples containing several radionuclides, especially if preceding radiochemical separations are to be largely or completely eliminated. The essential aspects of two programs for quantitative determinations and qualitative identifications are described. These programs are based on the least squares analysis of the total spectrum and the search, arrangement and processing of the photopeaks. With respect to their details the programs are adapted for application on the computer IBM-360/75. 相似文献
959.
960.