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1.
V. G. Baklykov V. N. Charushin O. N. Chupakhin V. N. Drozd 《Chemistry of Heterocyclic Compounds》1987,23(4):465-469
Thiobenzhydrazides undergo cyclization with N-alkyl-quinoxalinium salts to give 5-alkyl-substituted 1,4,4a,5,10,10a-hexahydro-1,3,4-thiadiazino[5,6-b]quinoxalines, which undergo isomerization to 10-alkyl-substituted thiadiazinoquinoxalines when they are heated in ethanol or in the presence of acids.See [1] for Communication 20.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 4, pp. 557–561, April, 1987. 相似文献
2.
V. I. Saloutin I. T. Bazyl' Z. E. Skryabina P. N. Kondrat'ev O. N. Chupakhin 《Russian Chemical Bulletin》1994,43(2):279-282
Reactions of pentafluorobenzoylpyruvic acid with amines afford the respective enamines. The intramolecular cyclization of the latter results inN-substituted 4-quinolone-2-carboxylic acids. Ammonia and triethylamine favor the cyclization of pentafluorobenzoylpyruvic acid to 2-carboxychromone.Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 2, pp. 299–302, February, 1994. 相似文献
3.
V. L. Rusinov A. Yu. Petrov O. N. Chupakhin 《Chemistry of Heterocyclic Compounds》1992,28(11):1335-1339
Two variants of a synthesis for nitropyrazolopyridines from aminopyrazoles and two- or three-carbon nitrosynthons are examined.For Communication 19 see [1].Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 11, pp. 1560–1564, November, 1992. 相似文献
4.
V. N. Charushin G. M. Petrova G. G. Aleksandrov L. G. Egorova A. I. Chernishev E. O. Sidorov N. A. Klyuev O. N. Chupakhin 《Chemistry of Heterocyclic Compounds》1987,23(4):426-435
Dibenzo[d,k]-1,3,6,10-tetraazatetracyclo[7.3.1.02,7.06,13]trideca-4,11-dienes undergo addition reactions at the C(2) carbon atom with alcohols and thiols, accompanied by cleavage of the C-N bond of the imidazoline ring, to generate diquinoxalino[1,2-a2,3-d]pyrrole derivatives.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 4, pp. 513–522, April, 1987. 相似文献
5.
L. Kh. Baumane R. A. Gavar Ya. P. Stradyn' O. N. Chupakhin V. L. Rusinov A. Yu. Petrov 《Chemistry of Heterocyclic Compounds》1985,21(5):582-587
1-Methyl- and 1-phenyl-substituted derivatives of 5-nitropyrazolo[3,4-b]pyridines are reduced at a dropping mercury electrode in a single one-electron wave with the formation of radical anions in interval of potentials from –0.94 to –1.06 V. Compounds unsubstituted at the N(1) nitrogen atom give an additional polarographic wave at E1/2 = –1.4 V due to the reduction of the deprotonated form (anion). The potentials and HFS constants of the ESR spectra of the corresponding electrochemically generated free radicals are given.For Communication 3, see [1].Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 5, pp. 689–693, May, 1985. 相似文献
6.
Kozhevnikov D. N. Kataeva N. N. Rusinov V. L. Chupakhin O. N. 《Russian Chemical Bulletin》2004,53(6):1295-1300
A simple procedure was developed for the synthesis of 1,2,4-triazines and their 4-oxides containing the ClCH2, Cl2CH, or CCl3 group at position 3 by cyclization of 2-aryl-2-hydrazono-1-oximinoethanes with the corresponding chloroacetonitriles. The reaction pathway depends on the number of halogen atoms in the acetonitrile used. The reactions with trichloroacetonitrile, monochloroacetonitrile, and dichloroacetonitrile afford 3-trichloromethyl-1,2,4-triazines, 3-chloromethyl-1,2,4-triazine 4-oxides, and a mixture of the corresponding dichloromethyltriazines and their 4-oxides, respectively. The reactions of 3-trichloromethyl-1,2,4-triazines with indoles and phenols are accompanied by tele-substitution with elimination of halogen from the trichloromethyl group to give 5-indolyl- (or 5-hydroxyphenyl)-3-dichloromethyl-1,2,4-triazines. 相似文献
7.
T. L. Pilicheva V. L. Rusinov O. N. Chupakhin N. A. Klyuev G. G. Aleksandrov S. E. Esipov 《Chemistry of Heterocyclic Compounds》1986,22(11):1250-1255
Non-charge-activated 6-nitroazolo[1,5-a]pyrimidines have been reacted with indoles, and the effects of substituents in the azole moiety of the substrate molecule have been examined.For communication 5, see [1].Translated from Khimiya Geterotsiklicheskikh Soedinenni, No. 11, 1544–1549, November, 1986. 相似文献
8.
V. N. Charushin M. G. Ponizovskii O. N. Chupakhin A. I. Rezvukhin G. M. Petrova Yu. A. Efremov 《Chemistry of Heterocyclic Compounds》1981,17(11):1129-1134
The reactions of substituted quinoxalinium, benzo[g]- and benzo[f]quinoxalinium, and pyrido[2,3-b]pyrazinium salts with anions of -dicarbonyl compounds give furo[2,3-b]-annelated systems with strictly determined regio- and stereoorientations.See [1] for Communication 3.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 11, pp. 1543–1548, November, 1981. 相似文献
9.
O. N. Chupakhin S. K. Kotovskaya S. A. Romanova V. N. Charushin 《Russian Journal of Organic Chemistry》2004,40(8):1167-1174
Features of 5(6)-fluoro-6(5)-X-benzofuroxans tautomerism were investigated. By 1H, 13C, and 19F NMR spectroscopy the direction of Boulton-Katritzky rearrangement in nitration, nitrosation, and azo coupling of fluorine-containing furoxanes was determined. 相似文献
10.
Krasnov V. P. Levit G. L. Korolyova M. A. Bukrina I. M. Sadretdinova L. Sh. Andreeva I. N. Charushin V. N. Chupakhin O. N. 《Russian Chemical Bulletin》2004,53(6):1253-1256
The influence of the reaction conditions (solvent, base) on the diastereoselectivity of acylation of (±)-3-methyl-2,3-dihydro-4H-1,4-benzoxazine with (S)-naproxen and N-tosyl-(S)-proline chlorides was studied. The highest diastereoselectivity was observed for the reaction carried out in benzene in the presence of aliphatic tertiary amines. 相似文献