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کاربرد نوع شرط:
- جایگاه : پژوهشی
- مجله: Physical Chemistry Research
- نوع مقاله: Journal Article
- کلمات کلیدی: Kinetics,Tautomerism,Rate constant,Tunneling effect,Heat capacity of activation
- چکیده:
- چکیده انگلیسی: The kinetics and mechanism of the reaction of 5-nitro-1H-benzo[d] imidazole to produce 6-nitro-1H-benzo[d] imidazole was studied by employing hybrid meta-density functional theory. MPWBlK/6-31+G** level calculations were carried out to obtain energies and optimize the geometries of all stationary points along the PES, and determine the harmonic vibrational frequencies. Two transition states (TS1 and TS2) and a chemically-energized intermediate (Int) are involved along the calculated potential energy surface. RRKM-TST was used to compute the temperature dependence of the rate constants, which were determined using nonlinear least-squares fitting at 273-1000 K. The Arrhenius plot for all reactions was shown positive temperature dependence. Thermodynamic parameters were also used to determine the stability and the extent of spontaneity of the reaction. The self-consistent reaction field (SCRF) was used with DFT energy, optimization, and frequency calculations to model systems in solution and compare them with the rate constants in the gas and solvent (water) phases. The variation of activation energy in the temperature range (273-1000 K) were determined in the gas and solvent phases. The heat capacity of activation of reactions ((∂E_a)/∂T) were also reported which is temperature dependent and is significant in low temperature.
- انتشار مقاله: 17-10-1395
- نویسندگان: Marzyeh Mohammadi,Seyedeh Leila Hashemi Dashtaki,Shapour Ramazani,Bahador Karami
- مشاهده
- جایگاه : پژوهشی
- مجله: Journal of Kerman University of Medical Sciences
- نوع مقاله: Journal Article
- کلمات کلیدی: Synthesis,Cytotoxic,Anti-oxidant,nano-catalyst,Ultrasound assisted,Bio-assay,Anti-viral
- چکیده:
- چکیده انگلیسی: Background: An efficient, promoted tri-component catalytic reaction between barbituric acid (or N,N-dimethyl barbituric acid), 4-hydroxy coumarin, and a wide range of aryl aldehydes using zinc oxide nanowires (ZnO NWs) to obtain some new 4-hydroxychromenylarylmethyl-6-hydroxypyrimidine-2,4-diones is described. Method: The reactants were successfully condensed via three C-C bond formation by zinc oxide nanowires (ZnO NWs) as an efficient, environmentally safe and recyclable nano catalyst to produce target molecules. In addition, the biological effects of synthesized products by the use of DPPH and acyclovir as positive controls and also Hep-2, vero cell, HSV-1, and adenovirus as four applied cell lines have been evaluated. Results: The results showed that synthesized products have anti-oxidant, cytotoxic and anti-viral activities and can offer promising prospect as biologically active agents. Conclusion: This achievement in an efficient and eco-friendly synthesis of novel analogous of hybrid molecules in aqueous media with special biological properties may engross chemists and pharmacologists as well as pharmacists in future.
- انتشار مقاله: 01-11-1396
- نویسندگان: Khalil Eskandari,Bahador Karami,Yaghoub Pourshojaei,Zahra Lori-Gooini,Elham Soltanipour-Joneghani,Mohammad-Taghi Moradi,Ali Asadipour
- مشاهده
- جایگاه : پژوهشی
- مجله: Iranian Journal of Catalysis
- نوع مقاله: Journal Article
- کلمات کلیدی: Solvent-free,Biginelli,Molybdate sulfuric acid,Quinazolinones/thiones
- چکیده:
- چکیده انگلیسی: Molybdate sulfuric acid (MSA) has been prepared and used as catalyst for the Biginelli synthesis of some quinazolinones/thiones under solvent-free conditions. The catalyst loading is low and it shows recyclability. This method has advantages such as avoidance of the organic solvents, high yield of pure products, short reaction times and operational simplicity.
- انتشار مقاله: 21-09-1392
- نویسندگان: Aigin Bashti,Bahador Karami,Saeed Khodabakhshi
- مشاهده