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Mohammadreza Moghaddam-manesh Hamid Beyzaei Mostafa Heidari Majd Sara Hosseinzadegan Kiarash Ghazvini 《Journal of heterocyclic chemistry》2021,58(7):1525-1530
In this study, anticancer, antibacterial (against hospital-isolated antibiotic-resistant Escherichia coli strains), antifungal, and antioxidant effects of synthesized heterocyclic compounds 5 and 7 containing thiazole core were examined. Cytotoxicity testing was utilized against MCF-7 breast cancer cells via MTT cell viability assay. Antibacterial and antifungal activities were checked out according to Clinical and Laboratory Standards Institute (CLSI) guidelines, and antioxidant properties were evaluated through scavenging 2,2-diphenyl-1-picrylhydrazyl (DPPH) free radicals. Results showed the viability of breast cancer cell lines was reliant on concentration of heterocycles and time of incubation. Synthetic compounds exhibited excellent antibacterial and antifungal properties base on their minimum inhibitory concentration (MIC), minimum bactericidal concentration (MBC), and minimum fungicidal concentration (MFC) values as well as high antioxidant activities according to their IC50 values. Higher anticancer and antibacterial properties were observed with compound 7; on the contrary, thiazole 5 had better antioxidant effects. They can be introduced as potent antimicrobial, antioxidant, and anticancer agents. 相似文献
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Eddie Wadbro Sara Zahedi Gunilla Kreiss Martin Berggren 《BIT Numerical Mathematics》2013,53(3):791-820
A finite element method for elliptic partial differential equations that allows for discontinuities along an interface not aligned with the mesh is presented. The solution on each side of the interface is separately expanded in standard continuous, piecewise-linear functions, and jump conditions at the interface are weakly enforced using a variant of Nitsche’s method. In our method, the solutions on each side of the interface are extended to the entire domain which results in a fixed number of unknowns independent of the location of the interface. A stabilization procedure is included to ensure well-defined extensions. We prove that the method provides optimal convergence order in the energy and the L 2 norms and a condition number of the system matrix that is independent of the position of the interface relative to the mesh. Numerical experiments confirm the theoretical results and demonstrate optimal convergence order also for the pointwise errors. 相似文献
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Sara Taha Gelan Rafat Fatma Aboshosha Fotouh R. Mansour 《Journal of Analytical Chemistry》2017,72(2):239-242
A simple portable spectrophotometer was constructed and used to perform analytical experiments. The developed model uses available tools and materials such as light emitting diode lamps, compact discs, plastic and cardboard boxes and a cell phone camera to build a design that illustrates the major components of spectrophotometers. The spectra of serial concentrations of KMnO4 (50?600 μM) were recorded and the values of absorbance were extracted at λmax to build the calibration curve. A linear relationship between the concentration and absorbance was obtained with the coefficient of determination 0.994. The model was also utilized to study the spectra of KMnO4, phenolphthalein and bromothymol blue in comparison with a Shimadzu UV-1800 spectrophotometer as a reference instrument. In spite of the differences in the observed spectra, the recorded λmax were almost identical to those measured by the developed model. The model was successfully used to determine the concentration of sodium alendronate through ligand-exchange complexation with ferric salicylate. 相似文献
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Vera C.M. Duarte Hélio Faustino Maria J. Alves António Gil Fortes Nuno Micaelo 《Tetrahedron: Asymmetry》2013,24(18):1063-1068
Two d-erythrose 1,3-butadienes were reacted with electrophilic achiral t-butyl 2H-azirine 3-carboxylate giving cycloadducts with good yields and moderate selectivity. The isomers could be separated to give the major (R)-isomers at C-2 in approximately 50% yield in both cases. Alternatively LACASA-DA methodology was applied to one of the reactions leading to homochiral (R)- and (S)-products by changing the chiral nature of an extra chiral BINOL inductor used. 相似文献
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Sara Bertuzzi Dr. Ana Gimeno Reyes Núñez-Franco Dr. Ganeko Bernardo-Seisdedos Sandra Delgado Dr. Gonzalo Jiménez-Osés Dr. Oscar Millet Prof. Dr. Jesús Jiménez-Barbero Dr. Ana Ardá 《Chemistry (Weinheim an der Bergstrasse, Germany)》2020,26(67):15643-15653
The interaction of human galectin-1 with a variety of oligosaccharides, from di-(N-acetyllactosamine) to tetra-saccharides (blood B type-II antigen) has been scrutinized by using a combined approach of different NMR experiments, molecular dynamics (MD) simulations, and isothermal titration calorimetry. Ligand- and receptor-based NMR experiments assisted by computational methods allowed proposing three-dimensional structures for the different complexes, which explained the lack of enthalpy gain when increasing the chemical complexity of the glycan. Interestingly, and independently of the glycan ligand, the entropy term does not oppose the binding event, a rather unusual feature for protein-sugar interactions. CLEANEX-PM and relaxation dispersion experiments revealed that sugar binding affected residues far from the binding site and described significant changes in the dynamics of the protein. In particular, motions in the microsecond-millisecond timescale in residues at the protein dimer interface were identified in the presence of high affinity ligands. The dynamic process was further explored by extensive MD simulations, which provided additional support for the existence of allostery in glycan recognition by human galectin-1. 相似文献