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41.
Chemistry of Phosphorus Ylides. Part 37. The Reaction of Phosphonium Ylides with Indoles and Naphthofurans. Synthesis of Phosphanylidenes,Pyrans, Cyclobutenes,and Pyridazine as Antitumor Agents 下载免费PDF全文
Soher S. Maigali Marwa El‐Hussieny Fouad M. Soliman 《Journal of heterocyclic chemistry》2015,52(1):15-23
The reaction of the stabilized phosphonium ylides 2a , 2b with indolinones 1a , 1b and naphthofuranone 13 afforded the corresponding propylidene and ethylidene derivatives 4a , 4b , 4c , 4d and 14a , 14b . On the other hand, the active phosphacumulenes 5a , 5b react with compounds 4a , 4b , 4c , 4d by [4 + 2]‐cycloaddition to give the stable phosphanylidene indole pyranones 6a , 6b , 6c , 6d , 6e , 6f , 6g , 6h . Although compounds 14a , 14b afforded the naphthofuropyrans 16a , 16b , 16c , 16d and triphenylphosphane. Moreover, the phosphallene ylide 7 react with compounds 4a , 4b , 4c , 4d and 14a , 14b to give phosphanylidenecyclobuteneindoline 9a , 9b , 9c , 9d and naphthalenones 18a , 18b , respectively. In addition, the naphthofuropyridazine 21 was obtained from the reaction of the hydrazone 19 and the phosphacumulene 5a . The antitumor activity of some of the new compounds was evaluated, in vitro, against colon and hepatocellular carcinoma cell lines. They showed values closed to that recorded by the reference drug Doxorubicin. 相似文献
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Fouad El-Diasty 《Vibrational Spectroscopy》2011,55(1):1-37
In this review the basis, recent developments and applications of coherent anti-Stokes Raman scattering (CARS) in the fields of spectroscopy and microscopy are dialed with. The nonlinear susceptibility of the investigated molecule induced by pump and Stokes laser beams employed in the CARS technique is discussed. The relation between the nonlinear susceptibility, the different CARS laser intensities and the phase matching condition between them is also presented. The structure of CARS spectrum is analyzed as a function of the physical characteristics of the different employed lasers. This includes laser half widths, interference effects, cross-coherence and saturation of the resultant CARS signal by stimulated Raman scatter process (SRS). The different broadening mechanisms for CARS spectral line such as pressure and Doppler broadening are demonstrated. The recent progress in CARS for the in situ reaction flame diagnosis due to its suitability for detection of vibrational-rotational excited gas molecules present in the electronic ground state is discussed. CARS diagnosis for liquid- and solid-phases including the progress in polymeric materials is considered. The applications of CARS microscopy are reviewed in the view of its recent advances to study chemical and biological systems. 相似文献
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In this paper, we study pseudo-slant submanifolds and their warped products in Kenmotsu manifolds. We obtain the necessary conditions that a pseudoslant submanifold is locally a warped product and establish an inequality for the squared norm of the second fundamental form in terms of the warping function. The equality case is also considered. 相似文献
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The 1,3-dipolar cycloadditions (13DC) of C-diethoxyphosphoryl-N-methylnitrone and N-(2-fluorophenyl) acrylamide have been studied using density functional theory (DFT) calculations at B3LYP/6-31G(d) level of theory. Our calculations show that this 13DC reaction takes place with complete ortho regioselectivity with endo stereoselectivity, which favours kinetically the formation of the ortho–endo cycloadduct, in agreement with the experimental observations. The inclusion of solvent effects does not modify the gas-phase selectivities but slightly decreases the reactivity of the reagents. Analysis of the bond order and charge transfer at the transition states indicates that this 13DC reaction takes place via a one-step asynchronous mechanism. Analysis of the DFT global reactivity indices and the Parr functions of the reagents allow us to provide an explanation of the regioselectivity of this 13DC reaction. 相似文献
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Mohammad Jabasini Ashraf A Ewis Feng Xu Guichen Ping Maged Fouad Toshikatsu Shinka Yutaka Nakahori Mitsuru Ishikawa Yoshinobu Baba 《Analytical sciences》2005,21(12):1537-1539
For the diagnosis of unexplained male infertility a multiplex PCR for 6 markers, which are well-known as candidate genes for studying male infertility and located on the human Y-chromosome, has been designed. The multiplex PCR products have been separated on a 12 channel microchip electrophoresis system, which can analyze different samples simultaneously. By combining the technologies of multiplex PCR with multichannel microchip electrophoresis, the number of the DNA markers that can be screened simultaneously is increased to be 72 marker (12 x 6) in a single run while the electrophoresis analysis time is reduced to be only 180 s. 相似文献
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Within a hadron bag valence quarks have a distribution of momenta, which, at low energies allows the kinematic scaling violations in deep inelastic scattering to be calculated. Using a simple model for this distribution we can succesfully account for the data between 2 and 6 (GeV/c)2. At higher momenta, “non-kinematic” effects are required. 相似文献
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