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91.
Aissa Hasnaoui Malika El Messaoudi Jean-Pierre Lavergne 《Journal of heterocyclic chemistry》1985,22(1):25-27
The cycloaddition of 3,5-dimethylthio-1,2,4-triazepine (1) to various dienophiles has been studied. 4-Phenyl-1,2,4-triazoline-3,5-dione, dimethyl acetylene dicarboxylate and meleic anhydride react with I to give the [4+2]π cycloadduct. The heterocyclic products were found to be formed via 1,3-sigmatropic rearrangement of this cycloadduct. 相似文献
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Samia Bouzroura Lamouri Hammal Fadila Balegroune Malika Hamadène Sophie Poulain 《合成通讯》2013,43(3):448-455
High‐yielding syntheses of an unpublished series of 2‐thioxo‐imidazolidin‐4‐ones 6 bearing an N‐ethoxycarbonyl and amidyl moieties an N1 and C5, respectively, are reported. These derivatives were obtained by intramolecular cyclization of 3‐ethylhydrazinoacetate 3,4‐dihydro maleimides 4 in the presence of ethyl or phenylisothiocyanate 2 under neutral conditions. 相似文献
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Muhammad Asim Akbar Hussain Safia Khan Javeria Arshad Tehmeena Maryum Butt Amina Hana Mehwish Munawar Farhat Saira Malika Rani Arshad Mahmood Naveed Kausar Janjua 《Molecules (Basel, Switzerland)》2022,27(18)
Hexanary high-entropy oxides (HEOs) were synthesized through the mechanochemical sol-gel method for electrocatalytic water oxidation reaction (WOR). As-synthesized catalysts were subjected to characterization, including X-ray diffraction (XRD), Fourier transforms infrared (FTIR) analysis, and scanning electron microscopy (SEM). All the oxide systems exhibited sharp diffraction peaks in XRD patterns indicating the defined crystal structure. Strong absorption between 400–700 cm−1 in FTIR indicated the formation of metal-oxide bonds in all HEO systems. WOR was investigated via cyclic voltammetry using HEOs as electrode platforms, 1M KOH as the basic medium, and 1M methanol (CH3OH) as the facilitator. Voltammetric profiles for both equiatomic (EHEOs) and non-equiatomic (NEHEOs) were investigated, and NEHEOs exhibited the maximum current output for WOR. Moreover, methanol addition improved the current profiles, thus leading to the electrode utility in direct methanol fuel cells as a sequential increase in methanol concentration from 1M to 2M enhanced the OER current density from 61.4 to 94.3 mA cm−2 using NEHEO. The NEHEOs comprising a greater percentage of Al, ([Al0.35(Mg, Fe, Cu, Ni, Co)0.65]3O4) displayed high WOR catalytic performance with the maximum diffusion coefficient, D° (10.90 cm2 s−1) and heterogeneous rate constant, k° (7.98 cm s−1) values. These primary findings from the EC processes for WOR provide the foundation for their applications in high-energy devices. Conclusively, HEOs are proven as novel and efficient catalytic platforms for electrochemical water oxidation. 相似文献
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Houari Benamar Lamberto Tomassini Alessandro Venditti Abderrazak Marouf Malika Bennaceur Marcello Nicoletti 《Natural product research》2016,30(22):2567-2574
The whole plant ethanolic extract of Solenanthus lanatus was used for the isolation of acetylcholinesterase inhibitors. A new pyrrolizidine alkaloid, 7-O-angeloylechinatine N-oxide, 1, was isolated together with three known compounds of the same class (3′-O-acetylheliosupine N-oxide, 2, heliosupine N-oxide, 3, and heliosupine, 4), by bioassay-guided approach. Their structures were elucidated by spectroscopic methods. All the isolated compounds showed inhibition activity against the AChE, with IC50 0.53–0.60 mM. 相似文献
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Taking the concept of operator with several Fuchsian variables of N.S. Madi (Ann. Mat. Pura Appl. (4) 163 (1993) 1–15), the results of K. Igari (J. Math. Kyoto Univ. 25 (1985) 341–355) are extended in this Note to show the existence of null-solutions for some of these operators. To cite this article: M. Belarbi et al., C. R. Acad. Sci. Paris, Ser. I 336 (2003). 相似文献
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Dr. Arianna Pina Malika Kadri Dr. Daniela Arosio Dr. Alberto Dal Corso Dr. Jean-Luc Coll Prof. Dr. Cesare Gennari Dr. Didier Boturyn 《Chemistry (Weinheim an der Bergstrasse, Germany)》2020,26(33):7492-7496
The use of multimeric ligands is considered as a promising strategy to improve tumor targeting for diagnosis and therapy. Herein, tetrameric RGD (Arg-Gly-Asp) peptidomimetics were designed to target αvβ3 integrin-expressing tumor cells. These compounds were prepared by an oxime chemoselective assembly of cyclo(DKP-RGD) ligands and a cyclodecapeptide scaffold, which allows a tetrameric presentation. The resulting tetrameric RGD peptidomimetics were shown to improve αvβ3 integrin binding compared with the monomeric form. Interestingly, these compounds were also able to enhance tumor cell endocytosis in the same way as tetrameric RGD peptides. Altogether, the results show the potential of the tetrameric cyclo(DKP-RGD) ligands for in vivo imaging and drug delivery. 相似文献
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Amadou Thierno Diallo Malika Tlemçani Memona Khan Jolanda Spadavecchia Nadia Djaker 《Particle & Particle Systems Characterization》2020,37(12):2000255
Complex-shaped nanoparticles as gold nanourchins (GNU) and nanorods (GNR) are very suitable agents in the case of photothermal therapy due to their photon-heat conversion ability in the red and near-infrared region (NIR). The quantification in heat generation of complex shaped nanostructures is an important key to predict the therapeutic effect of these nanoparticles. For that, the determination of the nanoparticles absorption cross section (σAbs) responsible for the heat generation is one of the important steps before any application. Although it is obvious to determine σAbs for spheres via Mie's theory, in the case of complex structures like GNU or GNR, this parameter is difficult to model. In this work, a new methodology is used to determine experimentally σAbs for both GNU and GNR. Experimental measurements of the photothermal properties of 100 nm size GNU and two different sizes of GNRs are studied regarding different parameters such as concentration, laser excitation wavelength, and exposure time. By using the heat transfer theory, the temperature elevation in the nanoparticles solutions is converted to temperature elevation at the nanoparticles surface and σAbs values are then calculated for both GNU and GNR in the NIR spectral region. 相似文献