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961.
The reaction between cis-[Pt(NH3)2Cl2], N1-(2"-tetrahydrofuranyl)-5-fluorouracil (HL), and NaOH (taken in a molar ratio of 1 : 1 : 1) or between cis-[Pt(NH3)2Cl2], HL, and Ag2O (taken in the molar ratio of 1 : 1 : 0.5) was used to synthesize complexes Ia (in the case of NaOH) or Ib (in the case of Ag2O) with composition Pt(NH3)2LCl. The model complex [Pt(NH3)3L]NO3 (II) was synthesized by the reaction between [Pt(NH3)3Cl]Cl, HL, AgNO3, and Ag2O (1 : 1 : 1 : 0.5). The obtained compounds were characterized by chemical analysis, chromatography, thermogravimetry, conductometry, potentiometry, IR, electronic, and NMR spectroscopies. Complexes Ia and Ib were found to have both similar and different properties. The structures of the compounds and the type of L coordination to platinum(II) were suggested. Cytotoxic properties of Iaand Ib were studied.  相似文献   
962.
The Web collection of electronic materials on Internet information resources for analytical chemistry (http://www.geokhi.ru/rusanalytchem/Resources/ default.htm) is reviewed. Data on the most informative sites maintained by institutions of various countries are systematized.  相似文献   
963.
The interaction of hydrogen atoms with a variety of alkali metal and alkaline-earth metal salts results not only in the recombination of these atoms but also in the displacement, into the gas phase, of free radicals (CaCl·(A 1 P 1/2, B 2 S +) and CaF·(A 2 P)) and metal atoms, including their excited species, which are detected spectroscopically. Transmission spectra indicate that the NaCl surface undergoes metallization when treated with a high-frequency discharge and a rarefied hydrogen flame. Combustion is affected by the gas-phase hydrogen atoms involved in the chain reaction and by the varying composition and properties of the surface. The concentration of Na atoms over the NaCl surface at 770 K is 109?1011 cm?3 in a stream of H atoms at 1 Torr and in the 2H2 + O2 flame at 4 Torr. The concentration of sodium atoms in the 2 P 3/2 and 2 P 1/2 excited states is ~5 × 106?5 × 108 cm?3. The role of the discovered reactions in combustion, pyrolysis, and plasma chemistry is discussed.  相似文献   
964.
Condensation of 4-chlorosulfonyl- and 4-fluorosulfonyl-benzoyl chlorides with p-dimethylamino--aminoacetophenone followed by cyclodehydration of the resulting amides leads to the formation of 4-(5-dimethylaminophenyl-2-oxazolyl)benzenesulfonyl halides, and the corresponding sulfonic ester, sulfomorpholide, sulfonamide, and sodium salt are synthesized from them. The spectral and luminescence properties of the compounds synthesized have been studied in toluene, ethanol, and DMF. The ability of the sulfonyl group to transmit the electronic effects of the substituents on it to the overall molecular -electron system of 2,5-diaryloxazole has been demonstrated. Salvation fluorochromia has been detected in polar solvents. In some of the compounds studied the Stokes shift exceeds 200 nm.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 2, pp. 234–237, February, 1993.  相似文献   
965.
Several new polymethine dyes of the cyanine and merocyanine series with 1-methyl-1H-imidazo [4,5-b]pyridine residues were synthesized, and their colors were studied. Replacement of the benzimidazole residue in the cyanine dyes by a l-methyl-1H-imidazo[4,5-b]-pyridine residue leads to deepening of the dye color.See [1] for communication II.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 11, pp. 1561–1565, November, 1971.  相似文献   
966.
The acylation of histidine with di-tert-butyl and di-tert-amyl pyrocarbonates has given the corresponding N,Nim-di-tert-alkoxycarbonyl derivatives. The N,Nim-di-tert-butoxycarbonyl derivative was obtained in the crystalline form by crystallization from benzene or carbon tetrachloride, or in the form of salts with cyclohexylamine, dicyclohexylamine, and diethylamine. N,Nim-di-tert-amyloxycarbonyl-histidine was characterized in the form of the salt with dicyclohexylamine.Institute of Biological and Medicinal Chemistry, Academy of Medical Sciences of the USSR, Moscow. Translated from Khimiya Prirodnykh Soedinenii, No. 3, pp. 379–383, May–June, 1980.  相似文献   
967.
968.
B. Moisan  A. Robert  A. Foucaud 《Tetrahedron》1974,30(16):2867-2872
The thermolysis of α-cyano α-keto epoxides to give dioxoles is a new rearrangement. The reactivity of the epoxides is dependent upon the nature of the substituents on the epoxide ring, and solvent polarity. When the reaction is carried in the presence of benzaldehyde, a 1,3 cycloadduct is obtained. These results are in good agreement with a carbonyl ylide intermediate.  相似文献   
969.
C.B. Kanner  U.K. Pandit 《Tetrahedron》1981,37(20):3513-3518
Conjugated esters and amides react with aryldiazonium salts at room temperature (MeCN) to form the corresponding iminium hydrazone derivatives, which can be thermally cyclized to cinnoline-3-esters and cinnoline-3-amides. In general the intermediate iminium salts derived from the enamine amides cyclize faster than those from the enamine esters. Furthermore, the ease of cyclization depends upon the structure of the base-component of the enamine ester or the amide and the substituent in the aryl moiety of the diazonium salt. The configurational structure of the iminium hydrazones, studied by NMR spectroscopy, has been shown to involve H-bonding of the hydrazonyl N-H with the ester or the amide CO group.  相似文献   
970.
A number of phenylmercury derivatives of 3-hydroxymethylene- and 3-aminomethylene-substituted 1-methyloxindoles, 1-indanones, and 1,3-indanediones were synthesized. It is shown that the preferred tautomeric structures of the potentially metallotropic and prototropic hydroxymethylene keto (hydroxy vinyl aldehyde) derivatives of the indicated compounds and 3-hydroxybenzo[b]-2-formylthiophene coincide precisely. An aminomethylene structure with an N-H bond is realized for the phenylmercury derivatives of the corresponding azomethines in all cases.Communication 28 from the series Benzenoid-Quinoid Tautomerism of Azomethines and Their Structural Analogs. See [1] for communication 27.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 1, pp. 65–68, January, 1979.  相似文献   
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