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61.
Majid M. Heravi Masoumeh Zakeri Narges Karimi Mina Saeedi Hossien A. Oskooie Niloofar Tavakoli-Hosieni 《合成通讯》2013,43(13):1998-2006
2,4,5-Trisubstituted imidazoles have been synthesized in excellent yields (85–95%) in the presence of 5 mol% of [(CH2)4SO3HMIM][HSO4] as a Brønsted acidic ionic liquid. 相似文献
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Reza Heydari Batool Tahamipour Niloofar Akbarzadeh Torbati Claudia Graiff Morteza Ziyaadini 《合成通讯》2013,43(15):2031-2041
1,10-Phenanthrolinium N-ylides react with ethyl cyanoacetate and aromatic aldehydes via a domino-Knoevenagel cyclization to produce a new class of tetrahydropyrrolo [1,2-a][1,10] phenanthrolines with four diastereoisomeric centers as stable helical compounds in a simple, mild, and efficient protocol in excellent yields. Explicit structural elucidation of compounds was accomplished by single-crystal x-ray diffraction. 相似文献
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Niloofar Abolhasani Khaje Charles K. Mobley Sandeep K. Misra Lindsey Miller Zixuan Li Evgeny Nudler Joshua S. Sharp 《Journal of the American Society for Mass Spectrometry》2018,29(9):1901-1907
Fast photochemical oxidation of proteins (FPOP) may be used to characterize changes in protein structure by measuring differences in the apparent rate of peptide oxidation by hydroxyl radicals. The variability between replicates is high for some peptides and limits the statistical power of the technique, even using modern methods controlling variability in radical dose and quenching. Currently, the root cause of this variability has not been systematically explored, and it is unknown if the major source(s) of variability are structural heterogeneity in samples, remaining irreproducibility in FPOP oxidation, or errors in LC-MS quantification of oxidation. In this work, we demonstrate that coefficient of variation of FPOP measurements varies widely at low peptide signal intensity, but stabilizes to ≈?0.13 at higher peptide signal intensity. We dramatically reduced FPOP variability by increasing the total sample loaded onto the LC column, indicating that the major source of variability in FPOP measurements is the difficulties in quantifying oxidation at low peptide signal intensities. This simple method greatly increases the sensitivity of FPOP structural comparisons, an important step in applying the technique to study subtle conformational changes and protein-ligand interactions. 相似文献
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Jalilian Niloofar Ebrahimzadeh Homeira Asgharinezhad Ali Akbar Molaei Karam 《Mikrochimica acta》2017,184(7):2191-2200
Microchimica Acta - The authors describe the synthesis of a nanosorbent for fast magnetic solid phase extraction of trace levels of Ag(I), Au(III), Pd(II) and Pt(II). It consists of graphene oxide... 相似文献
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Hemati Niloofar Shiri Farshad Hadidi Saba Mohammadi Elham Parvizi Rasool Hosein Farzaei Mohammad 《Structural chemistry》2021,32(3):1053-1060
Structural Chemistry - The antibiotic para-aminosalicylic acid (PAS) is decomposed into its decarboxylated product, meta-aminophenol, with a series of toxicity symptoms including hemolytic anemia.... 相似文献
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Dr. Prashanth K. Poddutoori Niloofar Zarrabi Dr. Andrey G. Moiseev Roger Gumbau‐Brisa Dr. Serguei Vassiliev Prof. Art van der Est 《Chemistry (Weinheim an der Bergstrasse, Germany)》2013,19(9):3148-3161
Two self‐assembled supramolecular donor–acceptor triads consisting of AlIII porphyrin (AlPor) with axially bound naphthalenediimide (NDI) as an acceptor and tetrathiafulvalene (TTF) as a secondary donor are reported. In the triads, the NDI and TTF units are attached to AlIII on opposite faces of the porphyrin, through covalent and coordination bonds, respectively. Fluorescence studies show that the lowest excited singlet state of the porphyrin is quenched through electron transfer to NDI and hole transfer to TTF. In dichloromethane hole transfer to TTF dominates, whereas in benzonitrile (BN) electron transfer to NDI is the main quenching pathway. In the nematic phase of the liquid crystalline solvent 4‐(n‐pentyl)‐4′‐cyanobiphenyl (5CB), a spin‐polarized transient EPR spectrum that is readily assigned to the weakly coupled radical pair TTF.+NDI.? is obtained. The initial polarization pattern indicates that the charge separation occurs through the singlet channel and that singlet–triplet mixing occurs in the primary radical pair. At later time the polarization pattern inverts as a result of depopulation of the states with singlet character by recombination to the ground state. The singlet lifetime of TTF.+NDI.? is estimated to be 200–300 ns, whereas the triplet lifetime in the approximately 350 mT magnetic field of the X‐band EPR spectrometer is about 10 μs. In contrast, in dichloromethane and BN the lifetime of the charge separation is <10 ns. 相似文献
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Cerium(IV) sulfate tetrahydrate, Ce(SO4)2·4H2O, is a novel inorganic solid acidic catalyst that efficiently catalyzes the synthesis of 2,3-dihydroquinazolin-4(1H)-ones via the one-pot three- component reaction of isatoic anhydride, aromatic aldehydes, and a nitrogen source(ammonium acetate, ammonium carbonate, ammonium chloride, or methylamine) under solvent-free conditions. The desired products are obtained in short reaction time with high yields. The catalyst is inexpensive and readily available and can be recovered conveniently and reused such that considerable catalytic activity can still be achieved after the fifth run. Easy work-up and avoiding the use of harmful organic solvents are other advantages of this simple procedure. 相似文献