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91.
Ya. P. Stradyn' G. Ya. Dubur Yu. I. Beilis Ya. R. Uldrikis A. É. Sausin' B. S. Chekavichus 《Chemistry of Heterocyclic Compounds》1975,11(11):1299-1303
Thirty-nine -substituted 1,4-dihydropyridine derivatives were subjected to electrochemical oxidation on a rotating platinum microelectrode in acetonitrile, and the Ep (E1/2) values were measured. A satisfactory linear correlation between the Ep and Taft. * constants of the substituents in the position was observed. A linear correlation of the Ep values with the 0, - and – constants also exists.See [1] for communication I.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 11, pp. 1525–1529, November. 1975. 相似文献
92.
Institute of Catalysis, Academy of Sciences of the USSR. Central Institute of Physical Chemistry, Academy of Sciences of the German Democratic Republic. Translated from Zhurnal Strukturnoi Khimii, Vol. 30, No. 1, pp. 29–33, January–February, 1989. 相似文献
93.
94.
É. I. Ivanov G. D. Kalayanov I. M. Yaroshchenko 《Chemistry of Heterocyclic Compounds》1992,28(7):795-797
Possible routes for synthesis of 2-haloimidazo[4,5-e][1,4]diazepines are discussed. Conditions for chlorination differ for homologs of caffeine, theophylline, and theobromine. For the caffeine homolog, both the 2-chloroand 2,6,6-trichloro products are obtained depending on the synthetic conditionsTranslated from Khimiya Geterotsiklicheskikh Soedinenii, No. 7, pp. 955–958, July, 1992. 相似文献
95.
Kicha A. A. Kalinovskii A. I. Levina É. V. Rashkes Ya. B. Stonik V. A. Elyakov G. B. 《Chemistry of Natural Compounds》1985,21(3):332-337
From the glycoside fraction of the starfishPatiria pectinifera, after its desulfation, an artefactural glycoside has been obtained: 29(-L-arabinofuranosyloxy)-5-stigmastane-3,6,8,15,16-pentaol (I). The structure of (I) was shown by1H and13C NMR spectra and mass spectra and by acetylation and high-temperature hydrogenation.Pacific Ocean Institute of Bioorganic Chemistry, Far Eastern Scientific Center, Academy of Sciences of the USSR, Vladivostok. Institute of Plant Substances, Academy of Sciences of the Uzbek SSR, Tashkent. Translated from Khimiya Prirodnykh Soedinenii, No. 3, pp. 356–361, May–June, 1985. 相似文献
96.
N. K. Kochetkov B. A. Dmitriev A. V. Nikolaev N. É. Bairamova 《Russian Chemical Bulletin》1977,26(7):1480-1483
Conclusions Trisaccharide-D-glucopyranosyl-(14)--L-rhamnopyranosyl-(1 3)-D-galactose was synthesized by using, 2-O-isopropylidene-4,6-O-ethylidene--D-galactopyranose for producing 1 3-rhamnosylgalactose, linkage.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 7, pp. 1609–1613, July, 1977. 相似文献
97.
L. Leite D. Jansone M. Fleisher H. Kazhoka J. Popelis N. Veretennikova I. Shestakova I. Domracheva E. Lukevics 《Chemistry of Heterocyclic Compounds》2004,40(6):715-724
The respective 4-(arylvinyl)lactones and compounds of the Michael adduct type were synthesized by the condensation of substituted benzaldehydes with 3-cyano-4,6,6-trimethyl-5,6-dihydro-2-pyranone in the presence of catalytic amounts of sodium hydroxide. It was shown by the semiempirical AM1 method that the indicated products can be formed through one and the same intermediate compound. Some of the synthesized phenylvinyl-5,6-dihydro-2-pyranones have a cytotoxic effect, and this corresponds to the prognosis of the OREX expert system. 相似文献
98.
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
99.
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
100.
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