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981.
P. Rodighiero A. Chilin G. Pastorini A. Guiotto P. Manzini 《Journal of heterocyclic chemistry》1990,27(4):1153-1158
A number of new methyltriazolocoumarins with a linear psoralen-like structure or an angular angelicin-like structure were synthetized. The syntheses were performed starting from the appropriate methylated 7-aminocoumarins which were nitrated, reduced and successively diazotized with concomitant cyclization to form the condensed triazolo ring. The new methyltriazolocoumarins show promising spectroscopic properties which are potentially predictive of their photochemical and photobiological behaviour. 相似文献
982.
N. S. Prostakov V. V. Kuznetsov E. E. Stashenko 《Chemistry of Heterocyclic Compounds》1989,25(11):1267-1271
It was established that the yields of a 4-allyl-4-aryl-aminopiperidines in the reaction of 4-aryliminopiperidines with allylmagnesium bromide increase significantly if the reaction is carried out in the presence of a crown ether. A number of previously unknown spiro[tetrahydroquinoline-2,4-piperidines] were obtained in the cyclization of 4-allyl-4-arylaminopiperidines in the presence of sulfuric acid.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 11, pp. 1514–1519, November, 1989. 相似文献
983.
I. G. Voigt-Martin 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》1988,100(10):1459-1459
984.
985.
986.
V. A. Makarov A. L. Sedov O. S. Anisimova V. G. Granik 《Chemistry of Heterocyclic Compounds》1996,32(6):699-707
Highly polarized enediamines of the a, -diamino--cyano--nitroethylene type have been obtained by the hydrolysis of 4-chloro-5-nitropyrimidines. Several chemical conversions of the enamines obtained have been studied, particularly leading to derivatives of 2-(cyanonitromethylene)imidazoline and -hexahydropyrimidine, and also to derivatives of N, N-bisvinylpiperazine and 7 methylene-1, 4-diazabicyclo(2.2. 1 ]heptane.Center for Drug Chemistry, All-Russian Chemical and Pharmaceutical Research Institute, Moscow 119815. Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 6, pp. 811–820, June, 1996. Original article submitted February 6, 1996.For Part 1, see [1]. 相似文献
987.
N. F. Kirillov V. V. Shchepin V. S. Melekhin 《Russian Journal of Organic Chemistry》2007,43(11):1628-1631
Methyl 1-(2-bromo-2-methyl-1-oxopropyl)-, 1-(1-bromocyclopentylcarbonyl)-, and 1-(1-bromocyclohexylcarbonyl) cyclobutanecarboxylates reacted with zinc and aromatic aldehydes to give, respectively, 7-aryl-2,2-dimethyl-6-oxaspiro[3.5]nonane-5,9-diones, 11-aryl-12-oxadispiro[3.1.4.3]tridecane-5,13-diones, and 12-aryl-13-oxadispiro[3.1.5.3]tetradecane-5,14-diones. 相似文献
988.
The influence exerted by a reinforcing additive, an aqueous suspension of 4D fluoroplastic (Teflon), on the structural, physicochemical, and service characteristics of the positive electrode of the lead battery was studied. A paste with polymer and carbon additives, extending the service life of the lead dioxide electrode, was developed for industrial use. 相似文献
989.
L. A. Zemnukhova L. G. Kolzunova E. D. Shkorina 《Russian Journal of Applied Chemistry》2007,80(6):1007-1011
Properties of liquid and dry extracts produced in treatment of buckwheat fruit shells (husk) and straw with water or an acid solution were studied. The conditions of pigment concentration from aqueous extracts by ultrafiltration were determined. 相似文献
990.