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Farrokhzadeh Abdolkarim Akher Farideh Badichi Soliman Mahmoud E. S. 《Applied biochemistry and biotechnology》2019,188(1):260-281
Applied Biochemistry and Biotechnology - There is currently considerable interest in SHP2 as a potential target for treatment of cancer. Mutation in SHP2, particularly the E76A mutation, has been... 相似文献
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Mercury(II) complexes with l-cysteine (H(2)Cys) in alkaline aqueous solutions have been structurally characterized by means of extended X-ray absorption fine structure (EXAFS) spectroscopy. The distribution of [Hg(Cys)(n)] (n = 2, 3, and 4) species in approximately 0.09 mol dm(-3) mercury(II) solutions with H(2)Cys/Hg(II) ratios varying from 2.2 to 10.1 has been evaluated by fitting linear combinations of simulated EXAFS functions for the separate complexes to the experimental EXAFS data, aided by (199)Hg NMR and Raman results. For the [Hg(Cys)(2)](2-) and [Hg(Cys)(3)](4-) complexes and the novel four-coordinated Hg(Cys)(4) species that dominates in solutions with excess of cysteine (H(2)Cys/Hg(II) > 5), the mean Hg-S bond distances were found to be 2.35(2), 2.44(2), and 2.52(2) Angstroms, respectively. The minor amount of the linear [Hg(Cys)(2)](2-) complex that can still be discerned in solutions with ratios up to H(2)Cys/Hg(II) = 5 was derived from the distinct S-Hg-S symmetric stretching Raman band at 334 cm(-1). From (199)Hg NMR spectra, the chemical shift of the Hg(Cys)(4) species was estimated to -340 ppm with an amount exceeding 85% in the highest excess of cysteine, consistent with the EXAFS data. 相似文献
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X-ray absorption spectroscopy (XAS) (edge and extended X-ray absorption fine structure (EXAFS)) has been applied to the characterization of three molybdenum(V,VI) monodithiolene complexes with unidentate coligands, [MoO(SC(6)H(2)-2,4,6-Pr(i)()(3))(2)(bdt)](-) (1), [MoOCl(SC(6)H(2)-2,4,6-Pr(i)(3))(bdt)](-) (2), and [MoO(2)(SC(6)H(2)-2,4,6-Pr(i)(3))(bdt)](-) (3) (bdt = benzene-1,2-dithiolate). These complexes are related to the active site in the xanthine oxidase and sulfite oxidase families and, as in the enzyme sites, bind monodentate thiolate. By comparison to the data of crystalline oxidized chicken sulfite oxidase, it is shown that complex 3, whose thiolate simulates binding by the highly conserved cysteine, is an accurate structural analogue of the oxidized site of this enzyme. Normalized edge spectra, EXAFS data, Fourier transforms, and GNXAS-based fit results are presented. As in earlier studies, this provides characterization of new analogue complexes by XAS to facilitate identification of related sites in proteins. 相似文献
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Meisam Shabanian Mehdi Khoobi Farideh Hemati Hossein Ali Khonakdar Khalil Faghihi Udo Wagenknecht Seyed esmaeil Sadat ebrahimia Abbas Shafiee 《中国颗粒学报》2015,(2):14-21
Hyperbranched polyethylenimine(PEI)-functionalized mesoporous silica(MCM@PEI) was synthesized and used to produce poly(vinyl alcohol)(PVA) nanocomposites.The modified nanofiller was characterized with infrared spectroscopy,thermogravimetric analysis,X-ray diffraction,scanning electron microscopy,transmission electron microscopy,and N2 adsorption.When compared with pure mesoporous silica(MCM),the MCM@PEI nanoparticles exhibited better dispersion in the PVA matrix.The effects of MCM@PEI on the thermal and flame properties of PVA nanocomposites were also studied.Improvement in the thermal properties was confirmed by enhanced thermal stability and char yield.Incorporation of MCM@PEI in PVA led to a significant drop in the heat release rate and the total heat release. 相似文献
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Ali Ramazani Abolfazl Momeni-Movahhed Farideh Gouranlou 《Phosphorus, sulfur, and silicon and the related elements》2013,188(4):903-907
Protonation of the highly reactive 1:1 intermediates, produced in the reaction between triphenylphosphine and dialkyl acetylenedicarboxylates, by 1-hydroxy-2-acetonaphthone leads to vinyltriphenylphosphonium salts, which undergo aromatic electrophilic substitution reaction with conjugate base to produce dialkyl 2-(3-acetyl-4-hydroxy-1-naphthyl)-3-(triphenylphosphoranylidene) butanedioates. Silica gel was found to catalyze conversion of dialkyl 2-(3-acetyl-4-hydroxy-1-naphthyl)-3-(triphenylphosphoranylidene) butanedioates to dialkyl 2-(3-acetyl-4-hydroxy-1-naphthyl)-2-butenedioates in solvent-free conditions at 90°;C in fairly good yields. 相似文献
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Simple synthesis of 7H-phenaleno[1,2-b]furan-7-one derivatives by one-pot, three-component reactions
The reaction of alkyl isocyanides with various aldehydes and 3-hydroxy-1 H-phenalene-1-one is described. The protocol offers facile and efficient synthesis of biologically interesting 9-(alkyl or arylamino)-7 H-phenaleno[1,2- b]furan-7-one derivatives from readily available starting materials in high yields. 相似文献
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Farideh Namvar Susan Azizi Rosfarizan Mohamad Amin Boroumand Moghaddam Mozhgan Soltani Fazele Moshfegh 《Research on Chemical Intermediates》2016,42(3):1571-1581
Palm pollen (PP) has been widely used in nutrition, pharmaceutical and cosmetic industries. In the present study, we explored the potential of PP in the synthesis of a silver nanoparticle (Ag NP). PP was used as both reducing and stabilizing agent. The Ag/PP nanocomposite was examined by field emission electron microscopy, X-ray diffraction, Fourier transform infrared (FT-IR) spectroscopy, ultraviolet spectroscopy and zeta potential measurement. The biosynthesized NPs showed surface plasmon resonance centered at 425 nm with an average particle size measured to be 23 nm and a zeta potential of ?30.9 mV. Prominent FT-IR signals were obtained and ascribed to phenolic and carbohydrate compounds involved in the formation of the Ag NPs, and proteins which participated in stabilization of the Ag NPs. The biologically synthesized Ag NPs were found to be extremely effective against E. coli (13.8 ± 0.25 mm) with a minimum inhibitory concentration of 20 µg/mL. Thus, such biosynthesized Ag NPs can be used in medicinal applications. 相似文献
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Ghorbani-Choghamarani Arash Rabiei Hossein Tahmasbi Bahman Ghasemi Banoo Mardi Farideh 《Research on Chemical Intermediates》2016,42(6):5723-5737
Research on Chemical Intermediates - Dopamine sulfamic acid-functionalized magnetic Fe3O4 nanoparticles (DSA@MNPs) were prepared by a very simple and inexpensive procedure using commercial... 相似文献