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61.
B. S. Chekavichus A. É. Sausin'sh G. Ya. Dubur 《Chemistry of Heterocyclic Compounds》1975,11(9):1077-1081
A number of new aryl esters of acetoacetic acid were obtained in the reaction of phenols with diketene in the presence of triethylamine. Reaction of the esters thus obtained with hexamethylenetetramine gave, for the first time, aryl esters of 1,4-dihydropyridine-3,5-dicarboxylic acid, the oxidation of which with chloranil gave the corresponding pyridines. 相似文献
62.
By means of Hartree—Fock energy variance calculations it has been shown that the specific electroncorrelation energy in extended cumulene molecules is approximately 0.3 eV/electron and the specific energy of interaction between -electron shells is 0.1 eV/electron.Translated from Teoreticheskaya i Éksperimental'naya Khimiya, Vol. 29, No. 6, pp. 514–517, November–December, 1993. 相似文献
63.
É. I. Ivanov 《Chemistry of Heterocyclic Compounds》1998,34(5):620-622
Alkylation of the cyclic homolog of xanthine in the methyl iodide-sodium hydride system as a function of the reagent-alkylating system ratio yields different products: for a 13 ratio of reagents, a homolog of caffeine is formed, while for a 12 ratio, a homolog of theobromine is formed. In contrast to xanthine, methylation of its cyclic homolog initially takes place at the imidazole ring and occurs in the sequence N(1), N(4), N(7).A. V. Bogatskii National Academy of Sciences of Ukraine, Odessa 270080. Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 5, pp. 701–703, May, 1998. 相似文献
64.
É. Lukevits I. Segal A. Zablotskaya S. Germane 《Chemistry of Heterocyclic Compounds》1996,32(6):682-688
The N-(2-hydroxyethyl)-1, 2, 3, 4-tetrahydroquinoline, -isoquinoline, and -silaisoquinoline, and their trimethyland triethylsilyl derivatives and the corresponding methiodides were synthesized. The acute toxicity and psychotropic activity of the compounds synthesized were studied.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 6, pp. 793–799, June, 1996. Original article submitted April 25, 1996. 相似文献
65.
66.
S. A. Giller A. V. Eremeev V. A. Kholodnikov É. É. Liepin'sh 《Chemistry of Heterocyclic Compounds》1975,11(9):1055-1058
Products of addition to both primary and secondary amino groups were obtained by reaction of 2-aminomethylethyleneimine with some acrylic acid derivatives. The structures of the compounds obtained were proved by means of their IR and PMR spectra and also by their subsequent chemical transformations.See [1] for communication X.Deceased.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 9, pp. 1212–1216, September, 1975. 相似文献
67.
É. S. Avanesyan V. N. Zaplishnyi G. M. Pogosyan 《Chemistry of Heterocyclic Compounds》1983,19(8):905-908
The peculiarities of the reaction of some substituted (in the benzene ring) 2,4-dichloro-6-aryloxy-sym-triazines with toluene under the conditions of the Friedel-Crafts reaction were investigated. Methods for the synthesis of 2-arloxy-4,6-bis(4-carboxyphenyl)-sym-triazines and their chlorides were developed. Cleavage of the ether bond to give a dihydro-sym-triazine structure occurs in the case of 2,4-dichloro-6-benzyloxy-sym-triazine.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 8, pp. 1125–1129, August, 1983 相似文献
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70.
The reactions of sulfur with alip-halogen derivatives of 1,2-diphenylethane, 1,2-diphenylethylene, and tetraphenylethane have been studied. A new method for the production of tetraphenylthiophene (from C6H5CHClCHClC6H5), benzothieno[3,2-b]benzothiophene (from C6H5CHClCCl2C6H5), and of 2-phenylbenzo[b] thiophene (from C6H5CHBrCHBrC6H5) has been developed. On being treated with sulfur, tetraphenyl-1,2-dichloroethane is converted into tetraphenylethylene. 1,2-Diphenylethylene reacts with sulfur in the presence of hydrogen bromide forming 2-phenylbenzo[b]thiophene and tetraphenylthiophene.For part XVII, see [1]. 相似文献