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1.
Procedures were developed for preparing 3,4,4'- and 2',3,4-triaminodiphenyl ethers by the reaction of 4-acetylaminophenol with, respectively, 4-nitro- or 2-nitrochlorobenzene, followed by nitration of the resulting 4-acetylamino-4'- or -2'-nitrodiphenyl ether, hydrolysis of the product, 4-acetylamino-3,4'- or -2',3-dinitrodiphenyl ether, and reduction of 4-amino-3,4'- or -2'-3-dinitrodiphenyl ether.  相似文献   
2.
Reaction of phenyl-ß-naphthylamines with formaldehyde and acetone in the presence of HCl and nitrobenzene in butanol solution leads to cyclization involving the naphthalene and phenyl rings, and formation of N-aryllepidine salts. 15 lepidine and 5, 6-benzoepidine salts are synthesized and characterized by their UV absorption spectra, as well as by their picrates.For Part LIII see [3].  相似文献   
3.
A compact set K in a smooth closed manifold M is said to be attractive, if on M there exists a system of differential equations, for which K is an asymptotically stable invariant set. It is proved that the set of attractive compacta is dense and its complement contains a dense set of type G in the space of all compacta of the manifold M endowed with two natural topologies.Translated from Zapiski Nauchnykh Seminarov Leningradskogo Otdeleniya Matematicheskogo Instituta im. V. A. Steklova AN SSSR, Vol. 143, pp. 170–175, 1985.  相似文献   
4.
Condensation of N-arylquinaldine salts with benzaldehyde and its o- and p-derivatives gives a series of styryl compounds. The absorption maxima of the hydroxystyryls are bathochromically shifted by 12–34 m, as compared with the unsubstituted analogs. Transformation of hydroxystyryl salts to the bases is linked with deepening of the color by 90–130 m.The other styryls were prepare similarly.  相似文献   
5.
Products of the reactions methyl N-[5(6)-(4-aminophenylsulfanyl)benzimidazol-2-yl]carbamate with phthalic anhydrides, involving the aniline nitrogen atoms, were obtained. Biological properties (embryotoxicity and toxicity) of the products and their mixtures with phase-transfer catalysts were studied. On this basis, new antihelminthic agents were developed.  相似文献   
6.
Procedures have been developed for the acylation of 4-amino-4'-nitrodiphenyl sulfide with an almost quantitative yield by the action of acetic anhydride in aprotic organic solvents and subsequent nitration of 4-acetylamino-4'-nitrodiphenyl sulfide with nitric acid in a mixture of acetic acid and an aprotic organic solvent with addition of a mixture of sulfuric and acetic acids by the end of the process.  相似文献   
7.
Nitration of 4-acetylamino-4'-nitrodiphenyl sulfide, 4-acetylamino-2'-nitrodiphenyl sulfide, and 4-acetylamino-2'-nitrodiphenyl ether yields respectively 4-acetylamino-3,4'-dinitrodiphenyl sulfide, 4-acetylamino-2',3-dinitrodiphenyl sulfide, and 4-acetylamino-2',3-dinitrodiphenyl ether.  相似文献   
8.
9.
AbstractExperimental data on the change in the electron density in the wake of a ballistic object traveling at velocities V =3.4–4.9 km/s in argon at pressures p =30–100 Torr are processed and analyzed. A reaction scheme is proposed which takes into account the recombination of charged particles, processes of ionic conversion, and the excited states of the atom. The solution of the equations of a nonequilibrium boundary layer for flow in the wake is used to formulate the inverse problem of determining the rate constants for dissociative recombination Ar 2 + +e→Ar+Ar and ternary recombination Ar++e+Ar→Ar+Ar. The “nearest-neighbor” approximation is used to obtain theoretically an expression for the ternary recombination coefficient as a function of temperature and pressure. Numerous solutions of inverse problems and a comparison with experiments demonstrates the validity of the expression obtained for the ternary recombination coefficient. It is shown that this expression is valid for moderate pressures and complements the Pitaevskii result for low pressures and the Langevin result for high pressures. Zh. Tekh. Fiz. 67, 12–18 (May 1997)  相似文献   
10.
Quinomerocyanines forming derivatives of rhodanine, oxazolone, and pyrazolone have been synthesized. The presence of a methoxy or a hydroxy group in the quinoline nucleus and in the p-position of a phenyl radical attached to the nitrogen leads to a bathochromic displacement of the absorption maximum as compared with the unsubstituted dye.For part LXV, see [12].  相似文献   
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