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1.
A. V. Vypirailenko I. B. Dzvinchuk M. O. Lozinskii 《Chemistry of Heterocyclic Compounds》2003,39(1):123-125
2-Phenacylbenzothiazole reacts with hydrazines and o-hydroxybenzaldehydes to give hydrazones and chalcones. These compounds tend to isomerize to benzothiazole-2-spiro-3'-pyrazoles and benzo[b]pyran-2-spiro-2'-benzothiazoles, respectively. 相似文献
2.
M. O. Lozinskii Yu. A. Fialkov V. S. Khomenko T. A. Pavich 《Theoretical and Experimental Chemistry》1990,26(2):228-231
A series of new adducts of fluorinated REE -diketonates with triphenylphosphine oxide was synthesized. The paths of their fragmentation under electron impact were investigated. It was shown that in contrast to the complex with 1,1,1,2,2,3,3-heptafluoro-7,7-dimethyloctane-4,6-dione, the complexes of europium with 1-trifluoromethoxy-1,1-difluoro-5,5-dimethylhexane-2,4-dione and 1, 1,1-trifluoro-5,5-dimethylhexane-2,4-dione form dimeric associates in the gaseous phase. The reasons for this difference in the behavior of the complexes and the possible structure of one of the dimers are discussed.Translated from Teoreticheskaya i Eksperimental'naya Khimiya, Vol. 26, No. 2, March–April, 1990. 相似文献
3.
M. O. Lozinskii A. F. Shivanyuk P. S. Pel'kis 《Chemistry of Heterocyclic Compounds》1971,7(4):439-442
The exchange and cyclization of phenyliminooxalyl chloride with ammonium thiocyanate, sodium azide, aniline, amidoximes, and diphenylthiourea, and with 2-aminopyridine, 2-aminobenzothiazole, and 2-amino- and 2-mercaptobenzimidazole were studied. The cyclization products are derivatives of thiazolidine, imidazo[1,2-a]pyridine, imidazo[2,1-b]benzothiazole, imidazo[1,2-a]benzimidazole, and thiazolo[3,2-a]benzimidazole. A trimer of 1-phenyltetrazole-5-carboxylic acid was obtained when an attempt was made to convert its azide to the corresponding isocyanate.See [1] for communication II.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 4, pp. 471–474, April, 1971. 相似文献
4.
Borisevich A. N. Samoilenko L. S. Lozinskii M. O. Rusanov E. B. Chernega A. N. 《Russian Journal of General Chemistry》2001,71(11):1767-1770
Reactions of acetylthioacetanilide with arylamines in acetic acid in the presence of sodium acetate give 3-arylaminothiocrotonanilides in good yields. When treated with -bromoacetophenone in acetone, these products are converted to substituted 4-hydroxy-2-thiazolinium bromides, one of which was dehydrated to obtain the corresponding thiazolium bromide. The structure of the heterocyclization products was confirmed by single crystal X-ray diffraction and NMR study of 2-acetonylidene-3,4-diphenyl-2,3-dihydrothiazole formed by dehydration of the corresponding 2-thiazolinium salt with simultaneous hydrolysis. 相似文献
5.
A. M. Demchenko V. A. Yanchenko V. V. Kisly M. S. Lozinskii 《Chemistry of Heterocyclic Compounds》2005,41(5):668-672
We have developed a method for synthesis of aryl isothiocyanates by means of thiocarbamoylation of aromatic amines by tetramethylthiuram disulfide followed by degradation of the intermediate N(1)-aryl-N,N-dimethylthiourea by concentrated HCl. We have shown that thiocarbamoylation of 4-amino-5-ethyl-4H-1,2,4-triazole-3-thiol occurs at the 2 position of the triazole ring, while thiocarbamoylation of 4-amino-3-methyl-6-phenyl-4,5-dihydro-1,2,4-triazin-5-one leads to the dihetaryl-substituted thiourea. We consider the possibility of using N(1)-aryl-N,N-dimethylthioureas as analogs of isothiocyanates in reactions with N-nucleophiles.__________Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 5, pp. 775–780, May, 2005. 相似文献
6.
Esters of (arylhydrazono)chloroacetic acid reacted with tris(hydroxymethyl)aminomethane in the presence of trimethylamine under mild conditions to give 3-(arylhydrazonoyl)-5,5-di(hydroxymethyl)-2-oxomorpholines. 相似文献
7.
Composite poly(vinyl alcohol) cryogels formed by the freezing–thawing of aqueous concentrated polymer solutions containing suspended filler were prepared and studied. The particles of unmodified silica gels were used as solid hydrophilic fillers and silica gels with grafted C2, C8, and C18 alkyl groups, as hydrophobic fillers. The granules of cross-linked dextran gel (Sephadex) swollen in water were used as soft hydrophilic fillers and lipophilic Sephadexes modified with propylene oxide groups, as soft hydrophobic fillers. It was shown that the microstructure and mechanical properties of such composites are affected by the presence of hydrophobic dispersed phase, namely, as the hydrophobicity of dispersed particles rises, the rigidity of composites increases with filler concentration at progressively lesser extent. 相似文献
8.
V. N. Britsun A. N. Borisevich A. N. Esipenko M. O. Lozinskii 《Russian Journal of Organic Chemistry》2007,43(1):103-107
N-Aryl-3-oxobutanethioamides react with 2-amino-1,3-thiazole (2-amino-1,3-benzothiazole) in acetic acid to give mixtures of 7-methyl-5H-[1,3]thiazolo[3,2-a]pyrimidine-5-thione (2-methyl-4H-pyrimido-[2,1-b][1,3]benzothiazole-4-thione) and 5-arylimino-7-methyl-5H-[1,3]thiazolo[3,2-a]pyrimidines (4-arylimino-2-methyl-4H-pyrimido[2,1-b][1,3]benzothiazoles), whose ratio depends on the nature of the aryl substituent in the initial butanethioamide. 相似文献
9.
I. B. Dzvinchuk A. V. Vypirailenko M. O. Lozinskii 《Chemistry of Heterocyclic Compounds》2004,40(9):1199-1206
Oxidative cyclocondensation of 2-aroylmethyl-1H-benzimidazoles with o-aminothiophenol gave the previously unknown 3-aryl-2-(2-benzimidazolyl)-4H-1,4-benzothiazines and (or) the isomeric 2H-1,4-benzothiazines. 2-(4-Nitrophenacyl)-1H-benzimidazole and 2-phenacylbenzothiazole gave 4H-1,4-benzothiazines which are not liable to isomerize but the reaction of the first compound is complicated by a hydrolytic fission which yields 2-[2-(4-nitrobenzoylamino)phenylthiomethyl]benzimidazole. A mixture of dimethylsulfoxide, acetic acid, and water was used as oxidant and solvent. The effect of the substituent and of the solvent on the tendency of the products to undergo prototropic isomerization in the benzothiazine ring have been studied. 相似文献
10.
L. Yu. Chumakova A. M. Demchenko A. N. Krasovsky T. V. Dolishnyak M. O. Lozinskii 《Chemistry of Heterocyclic Compounds》2003,39(8):1002-1012
3-Ethoxycarbonyl-2-(N-R-thioureido)-4,5,6,7-tetrahydrobenzo[b]thiophenes were obtained by the reaction of 2-amino-3-ethoxycarbonyl-4,5,6,7-tetrahydrobenzo[b]thiophene with isothiocyanates and of 3-ethoxycarbonyl-2-isothiocyanato-4,5,6,7-tetrahydrobenzo[b]thiophene with primary and secondary amines. The cyclization paths of the products leading to derivatives of thieno[2,3-d]pyrimidine and thieno[2,3-d]-1,3-thiazine were studied. The corresponding S-substituted derivatives were obtained by the alkylation of 3-R-2-thioxo-3,4,5,6,7,8-hexahydrobenzo[b]thieno[2,3-d]pyrimidin-4-ones. 相似文献