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51.
p-tert-Butylcalix[4]arenes substituted at the lower rim by acetic acid hydrazide residues reacted with methoxy(ethoxy)acridine and fluoren-9-one derivatives to give a series of calixarenes containing N′-fluorenylidene- and N′-acridinylacetohydrazide residues. It was found that modification of the hydrazide moiety does not affect the conformation of the initial macroring and that it can lead in some cases to unsymmetrically substituted calixarenes.  相似文献   
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Reaction products have been isolated from SO2–L–H2O–О2 systems (L = ethylenediamine, N,N,N′,N′-tetramethylethylenediamine, piperazine, and morpholine) as onium salts [H3NCH2CH2NH3]SO4, [(CH3)2NHCH2CH2NH(CH3)2]SO4, [(CH3)2NHCH2CH2NH(CH3)2]S2O6 ? H2O, [C4H8N2H4]SO3 ? H2O, [C4H8N2H4]S2O6, [C4H8N2H4]SO4 ? H2O, [O(C2H4)2NH2]2SO4 ? H2O. The prepared compounds have been characterized by X-ray diffraction analysis, X-ray powder diffraction, IR and mass spectroscopy.  相似文献   
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The properties of complex compounds produced by template condensation of salicylideneaminoguanidines with salicylaldehyde on a nickel(II) ion matrix are studied. It is shown that the potassium ion in a nitrogen-substituted triazacyclic complex can be replaced by a tetrabutylammonium cation. The electronic structure of the compounds obtained is characterized using UV, IR, and (1H, 13C) NMR spectroscopies. A chelate compound produced from nitroaminoguanidine was found to exhibit the effect of electron density redistribution involving nickel AO. As a result, two benzene rings of the complex anion become nonequivalent.  相似文献   
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2,7-Dihydroxy-9-fluorenone was alkylated with alkyl halides in acetone in the presence of potassium carbonate to prepare 2,7-dialkoxy-9-fluorenones prone to mesomorphism. Mesomorphic properties are characteristic of the compounds containing in the alkoxyl chain from 5 to 14 carbon atoms. When slowly cooled, such compounds tend to vitrify in the liquid crystal phase.  相似文献   
58.
New ylidene and spirocyclopropyl derivatives of cholestanone and dehydroepiandrosterone series were synthesized and their structure was determined by X-ray analysis. These compounds may be used as chiral dopants for cholesteric liquid crystal compositions which are applied in bistable displays with low power consumption. The ability of the synthesized substances to induce cholesteric mesophase in 4′-pentyl-1,1′-biphenyl-4-carbоnitrile nematic solvent was examined. The highest values of the helical twisting power |β| (190.0?±?2.3) and (165.5?±?1.9) µm?1 mol pats?1 were showed by (E)-2-{[3-(1,1′-biphenyl-4-yl)-1-phenyl-1H-pyrazol-4-yl]methyldene}-cholestanon and (1S,2S)-1-(1-phenyl-3-(4-methoxyphenyl)-1H-pyrazole-4-yl)-2,16′-spirocyclopropyldehydroepiandrosterone, correspondingly.  相似文献   
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It has been shown that dimethylamino-substituted 2,5-diaryloxazoles and 2,5-diaryl-1,3,4-oxadiazoles undergo heterocyclization under Vilsmeier-Haack conditions with the participation of the dimethylamino group to form quinazolinium salts. The oxazole ring can also be formylated at the free 4 position. In alkaline medium the quinazolinium ring is readily hydrolyzed with desalkylation.  相似文献   
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