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51.
Asymmetric Cycloaddition: An Efficient Synthesis of Enantiopure Isoxazolines Substituted with Carbohydrate Analogues 下载免费PDF全文
Omar K. Al‐Duaij Naoufel Ben Hamadi Lotfi Khezemi 《Journal of heterocyclic chemistry》2016,53(2):408-413
A simple and convenient method for the synthesis of heterocycles substituted with carbohydrate analogs is described. The chiral optically pure five‐membered glycoconjugates containing the isoxazoline unit were obtained by an aromatic nitrile oxides cycloaddition with 1‐phenyl‐1,2‐dihydro‐pyridazine‐3,6‐dionyl N‐glycoside derivatives. 相似文献
52.
A new and efficient procedure for the synthesis of 3,5-disubstituted-2,6-dicyanoaniline derivatives by CoFe2O4@SiO2-PA-CC-guanidine magnetic nanoparticles (MNPs) was reported. 3,5-Disubstituted-2,6-dicyanoaniline derivatives were synthesized from malononitrile, aldehydes, and β-nitrostyrene derivatives in good yields. MNPs used for the synthesis of aniline derivatives were easy to recover and reuse. The CoFe2O4@SiO2-PA-CC-guanidine MNPs were characterized by Fourier-transform infrared spectroscopy, scanning electron microscopy, energy-dispersive X-ray spectroscopy, X-ray diffraction, thermogravimetric analysis, and vibration sample magnetometry techniques. 相似文献
53.
Lotfi Z Ismail Hussein M Abdel Moneim 《Journal of Physics and Chemistry of Solids》2003,64(8):1405-1411
The effect of longitudinal and transverse modes of oxygen plasma generated by microwave source with frequency 2.45 GHz has been used to characterize polycrystalline samples of NdBa2Cu3O6+δ (Nd-123) high Tc-superconductor. For this purpose we have developed a simple oxidation technique, used by us earlier, to investigate the effect of different modes on the appearance of superconductivity in Nd-123. Our main results show that the mode of microwave plasma and time of exposure can control the local arrangement of oxygen vacancies in CuOδ basal plane. Samples exposed to the transverse mode reveals a well ordered orthorhombic phase transition while the longitudinal modes caused the samples to have a non-superconducting tetragonal structure for all of the exposure time. The Tc vs. δ curve does not show the typical 60 K plateau corresponding to the ortho-II phase. The IR spectrum show bands at shorter wavelengths which corresponding to the metal oxides. 相似文献
54.
Daniela Manova Florian Gallier Lotfi Tak-Tak Lyubov Yotava Nadège Lubin-Germain 《Tetrahedron letters》2018,59(21):2086-2090
The amidation reaction is of a very particular interest, especially in the pharmaceutical industry and always requires the activation of the acid with a large excess of reactants. Therefore, a large amount of waste is generated. In order to reduce the environmental impact of such reaction, we have developed enzymatic amidation conditions which are compatible with a wide range of amines and acids, in particular with the biologically relevant lipoic acid. Water is the only by-product generated during this reaction thus a very high atom economy is obtained. In addition, we have shown that the lipase can be recovered and reused several times without a significant loss of activity. 相似文献
55.
Iran Sheikhshoaie Najmeh Lotfi Joachim Sieler Harald Krautscheid Moj Khaleghi 《Transition Metal Chemistry》2018,43(6):555-562
Three Ni(II) and Zn(II) complexes [Ni(L1)], [Ni(L2)], and [Zn(L3)(DMSO)] (L1 = 2,3-bis(2-hydroxybenzylideneimino)-2,3-butenedinitrile, L2 = 2,3-bis(2-hydroxy-3-methoxybenzylideneimino)-2,3-butenedinitrile, L3 = 2,3-bis(2-hydroxy-1-naphthylideneimino)-2,3-butenedinitrile) were obtained in DMSO by one-pot syntheses. The complexes were characterized by physicochemical and spectroscopic methods. Also, their solid-state structures were determined by single-crystal X-ray diffraction. The geometries of the Ni(II) and Zn(II) complexes were square planar and square pyramidal, respectively. The complexes were screened in vitro against a fungal species and eight species of bacteria, revealing their antimicrobial activity. 相似文献
56.
Lotfi Rghioui Lahcen El Ammari Larbi Benarafa Jean Pierre Wignacourt 《Acta Crystallographica. Section C, Structural Chemistry》2002,58(7):i90-i91
The crystal structure of dipotassium caesium ytterbium bis(phosphate) is built up from regular independent PO4 tetrahedra and YbO6 octahedra sharing corners and arranged in layers. The structure is, in many respects, similar to that of glaserite. 相似文献
57.
58.
Peykani Pejman Hosseinzadeh Lotfi Farhad Sadjadi Seyed Jafar Ebrahimnejad Ali Mohammadi Emran 《Fuzzy Optimization and Decision Making》2022,21(2):197-261
Fuzzy Optimization and Decision Making - Fuzzy data envelopment analysis (FDEA) is one of the most applicable approaches for performance assessment of peer decision making units under ambiguity... 相似文献
59.
Muhammad Muzammal Hussain Dr. Muhammad K. Majeed Prof. Haitao Ma Prof. Yunpeng Wang Dr. Adil Saleem Mina Lotfi 《Chemistry (Weinheim an der Bergstrasse, Germany)》2022,28(2):e202103220
Organic resin cross-linking ZIF-67/SiO2 superhydrophobic (SHPB) multilayer coating was successfully fabricated on metal substrate. The perfluoro-octyl-triethoxy silane (POTS) modified ZIF-67 and SiO2 coating was applied on primary coated polytetrafluoroethylene (PTFE) and epoxy resin (EP) via spray coating method. Here, we present that the robust superhydrophobicity can be realized by structuring surfaces at two different length scales, with a nanostructure design to provide water repellence and a microstructure design to provide durability. The as-fabricated multilayer coating displayed superior water-repellence (CA=167.4°), chemical robustness (pH=1–14) and mechanical durability undergoing 120th linear abrasion or 35th rotatory abrasion cycle. By applying different acidic and basic corrosive media and various weathering conditions, it can still maintain superior-hydrophobicity. To get a better insight of interaction between inhibitor molecules and metal surface, density functional theory (DFT) calculations were performed, showing lower energy gap and increased binding energy of ZPS/SiO2/PTFE/EP (ZPS=ZIF-67+POTS) multilayer coating compared to the ZIF-67/SiO2/PTFE/EP, thereby supporting the experimental findings. Additionally, such coatings may be useful for applications such as anti-corrosion, self-cleaning, and anti-icing multi-functionalities. 相似文献
60.
Mosbah Habib Chahdoura Hassiba Mannai Asma Snoussi Mejdi Aouadi Kaïss Abreu Rui M. V. Bouslama Ali Achour Lotfi Selmi Boulbaba 《Applied biochemistry and biotechnology》2019,187(3):1113-1130
Applied Biochemistry and Biotechnology - A series of enantiopure isoxazolidines (3a–c) were synthesized by 1,3-dipolar cycloaddition between a (−)-menthone-derived nitrone and various... 相似文献