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31.
32.
The reactions of 2-acetyldimedone and 2-acetyl-3-methoxy-5,5-dimethylcyclohex-2-en-1-one with 3,4-diaminobenzophenoneproduce2-[1-(2-amino-5-benzoylphenyl)amino]ethylidene-5,5-dimethyl-1,3-cyclohexanedioneand 2-acetyl-3-(2-amino-5-benzoylphenyl)amino-5,5-dimethylcyclohex-2-en-1-one, which are cyclized by the action of hydrochloric acid, yielding the respective hydrochlorides of 8-benzoyl- and 7-benzoyl-3,3,11-trimethyl-2,3,4,5-tetrahydro-1H-dibenzo[b,e][1,4]diazepin-2-ones. Hydrolytic cleavage of the 8-benzoyl derivative leads to 2-acetyl-3-(2-amino-4-benzoylphenyl)amino-5,5-dimethylcyclohex-2-en-1-one. A similar cleavage to form 2-acetyl-3-(2-aminophenyl)amino-5,5-dimethylcyclohex-2-en-1-one is observed for the known hydrochloride of 3,3,11-trimethyl-2,3,4,5-tetrahydro-1H-dibenzo[b,e][1,4]diazepin-2-one. The structures of the products were confirmed by PMR spectra and x-ray diffraction data.Riga Technical University, Riga LV-1658. Latvian Institute of Organic Chemistry, Riga LV-1006. University of Cincinnati, Ohio, USA. Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 3, pp. 379–391, March, 1997.  相似文献   
33.
Conclusions In contrast to the unfluorinated anilides, the trifluoro- and trichloroacetyl derivatives of pentafluoroaniline form trichlorophosphazopentafluorobenzene when treated with PCl5. The same compound was obtained by the reaction of pentafluoroaniline with PCl5.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 11, pp. 2635–2637, November, 1978.  相似文献   
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Abstract

The interaction of Li-diethylbenzylphosphonate 1-Li with aldehydes 2 is studied at different reaction conditions, the corresponding β-hydroxyethanephosphonate 3 being isolated. It is found that in these cases the aldol stage of the HWE reaction is not stereoselective or threo isomers predominate. The elimination stage leads only to trans-alkene due to the electron and steric influence of the substituents at the phosphorus atom.  相似文献   
36.
The synthesis and characterization of several new phosphorus-containing partially lower rim substituted derivatives of 5,11,17,23-tetra(t-butyl) calix(4)arene (I) and 5,11,17,23-tetra(t-octyl)calix(4)arene (II), namely 5,11,17,23-tetra(t-butyl)-25,27-dihydroxy-26,28-bis(diphenylphosphinoyl-oxy) calix(4)arene (IV); 5,11,17,23-tetra(t-butyl)-25-hydroxy-26,27,28-tris(tetramethyldiamido-phosphinoyl-oxy) calix(4)arene (Vb); 5,11,17,23-tetra(t-butyl)-25,27-dihydroxy-26,28-bis(dimethyl-phosphinoyl-methoxy) calix(4)arene (VI); 5,11,17,23-tetra (t-octyl)-25,27-dihydroxy-26,28-bis(dimethyl-phosphinoyl-methoxy) calix(4)arene (VII) are reported. The structure of the synthesized calix(4)arene derivatives are identified and confirmed by elemental analysis, IR, 1H, 13C, 31P{1H} NMR spectroscopy and mass spectrometry as and X-ray crystallographic analysis of 5,11,17,23-tetra(t-butyl)-25,27-dihydroxy-26,28-bis(dimethyl-phosphinoyl-methoxy) calix(4)arene VI. According to the NMR spectra, all calix(4)arenes are in cone conformation.  相似文献   
37.
Cross-coupling of 2-(biphenyl-4-yl)pyrroles derived from 1-(biphenyl-4-yl)ethanone oximes and acetylene with 3-bromo-1-phenylprop-2-yn-1-one on aluminum oxide gave 3-[5-(biphe-nyl-4-yl)pyrrol-2-yl]-1-phenylprop-2-yn-1-ones in 35–46% yields.  相似文献   
38.
Bis(dialkylamides) of phosphoryl-substituted α,ω-dicarboxylic acids were synthesized and their biological activity was studied.  相似文献   
39.
The possibility of synthesizing oxygen-ionic conductors from substituted bismuth molybdates containing [Bi12O14] n 8n+ columns, MoO4 tetrahedra, and isolated Bi ions in their structure was studied. The specifics of their structure and electric conductivity were investigated. The general formula of the solid solutions can be recorded as Bi13Mo5 ? x Me x O34 ? δ, where Me is the fouror five-valent d metal (Ti, Zr, V, Nb). The electric conductivity of doped bismuth molybdates considerably increased compared with that of the matrix compound. The electric conductivity reached 5.5 × 10?3 S cm?1 at 700°C and 1.8 × 10?4 S cm?1 at 350°C for the zirconium-doped compound with x = 0.4. The porosity of the ceramics was less than 5%; the thermal expansion coefficient was of the order of 14 × 10?6 K?1. Based on the set of their characteristics, these compounds are recommended as materials for membranes of electrochemical devices.  相似文献   
40.
Detection of staphylococcal toxins presents a great interest for medical diagnostics. Screening of clinical samples for the presence of several types of staphylococcal toxins using traditional methods—biological tests on animals or cell cultures as well as ELISA—is laborious. Multiplex detection methods would simplify testing. We have designed an xMAP-based assay to detect three staphylococcal toxins—enterotoxins A and B (SEA and SEB) and toxic shock syndrome toxin (TSST)—in cultural supernatants obtained from different strains of Staphylococcus aureus. The limits of detection of SEA, SEB, and TSST multiplex detection in S. aureus growth medium were 10, 1,000, and 5 pg/mL, respectively. Fifty-nine samples of S. aureus cultural supernatants were tested with the xMAP assay. The developed assay has proved highly effective detection of the natural toxins in the samples obtained due to bacterial cells cultivation. In prospect, the developed test system can be used in clinical diagnostics and in monitoring of foodstuffs and environmental objects.  相似文献   
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