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1.
Ethyl esters of 1-(7-Z-1-ethyl-6-fluoro-4-oxo-1,4-dihydroquinoline-3-carbamoyl)-5-X-6,7,8-trifluoro-4-oxo-1,4-dihydroquinoline-3-carboxylic acids (X = H, F; Z = pyrrolidino-, piperidino-, hexamethylenimino-, morpholino-, thiomorpholino-) have been synthesized by the interaction of quinolone-3-carboxylic acid hydrazides with ethyl esters of 3-ethoxy-2-(polyfluorobenzoyl)acrylic acid . It was shown possible to cyclize intramolecularly the esters obtained with the formation of 1,3,4-oxadiazino[6,5,4-i,j]quinoline derivatives.  相似文献   
2.
3-(2-Acylhydrazino)-2-tetra(penta)fluorobenzoylacrylates are readily converted to acylamino-substituted quinolones and, under more forcing conditions, annelation of oxadiazine ring occurs. We have identified the possible cyclization of the mentioned acrylates to 4,5-substituted pyrazoles.  相似文献   
3.
Electronic transitions of the linear MgC 4H and MgC 6H radicals have been observed in the gas phase using laser-induced fluorescence spectroscopy. The species were prepared in a supersonic expansion by ablation of a magnesium rod in the presence of acetylene, diacetylene, or methane gas. The transitions were recorded in the 445-446 nm region and assigned to the A (2)Pi- X (2)Sigma (+) systems ( T 0 = 22 431.978(7) and 22 090.08(7) cm (-1)) based on previously reported mass-selective resonance-enhanced ionization spectra and the rotational structure. A spectral fit in MgC 4H yields the rotational constants B' = 0.04619(19) cm (-1) for the X (2)Sigma (+) state and B' = 0.04748(20) cm (-1) for A (2)Pi. Astrophysical implications are briefly addressed.  相似文献   
4.
Depending on the conditions, 3-(4-R-thiosemicarbazido)-2-polyfluorobenzoylacrylates can be converted into the corresponding potassium salts, [1,3,4]thiadiazino[6,5,4-ij]quinolines, and pyrazole or 1,3,4-thiadiazole derivatives.  相似文献   
5.
The interaction of C-aryl-substituted amidrazones and S-methylisothiosemicarbazide with 3-ethoxy-2-polyfluorobenzoylacrylates results in corresponding N-(quinolin-1-yl)amidines that undergo conversion into derivatives of 1,2,4-triazino[5,6,1-i,j]quinoline by heating in acetic anhydride.  相似文献   
6.
The heating of ethyl 3-azolylamino-2-polyfluorobenzoylacrylates in acetonitrile in the presence of KF gave rise to derivatives of 1-azolyl-substituted quinolones or azolo[1,5-a]pyrimidines.  相似文献   
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8.
A comparatively new procedure is described for the nonlinear electrophoresis of proteins. Movement and separation of complexes formed by proteins and ionic detergents is first experimentally demonstrated for SDS rainbow colored protein molecular weight markers (Amersham). This result was revealed by SDS-PAGE in an asymmetric zero average pulsed electric field with a peak amplitude of up to 300 V cm(-1) and a frequency of 100 Hz. The highest molecular weight fractions were found to have the highest nonlinear drift velocity. A two-dimensional map of distribution of the protein complexes developed using nonlinear electrophoresis followed by SDS gel electrophoresis in an orthogonal direction, reveals nonuniform distribution of the fractions. Nonlinear electrophoresis can be run without electrode chambers, since the buffer electrolyte is not used up in alternating electric fields. Thus, this new type of electrophoresis can have advantages in microfluidic systems and biochips. Also possible uses are discussed of nonlinear electrophoresis via nonlinear focusing of protein-detergent complexes for further improvement of the SDS-PAGE technique for the separation and examination of these large hydrophobic complexes.  相似文献   
9.
The work is dedicated to improvement of efficiency of storage and processing of food raw materials using radiation technologies. International practice of radiation processing of food raw materials is presented and an increase in the consumption of irradiated food products is shown. The prospects of using radiation technologies for the processing of food products in Russia are discussed. The results of studies of radiation effects on various food products and packaging film by γ radiation and accelerated electrons are presented.  相似文献   
10.
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