In this work,we describe a new strategy for the electrochemical determination of captopril（CA） using ferrocenemonocarboxylic acid as a mediator and multiwall carbon nanotubes as sensors in aqueous solution at pH 7.0...In this work,we describe a new strategy for the electrochemical determination of captopril（CA） using ferrocenemonocarboxylic acid as a mediator and multiwall carbon nanotubes as sensors in aqueous solution at pH 7.0.The diffusion coefficient（D）,and the kinetic parameters such as electron transfer coefficient（α）.and heterogeneous rate constant（kh）,for CA were also determined using electrochemical approaches.Under the optimized conditions,the electrocatalytic oxidation peak current of captopril showed two linear dynamic ranges with a detection limit of 0.3×10^-6 mol L^-1 captopril.The linear calibration range was 0.8×10^（-6） to 65×10^-6 mol L^-1 using cyclic voltammetry.Finally,this modified electrode was also examined as a selective,simple and precise new electrochemical sensor for the determination of captopril in real samples such as drug and patient human urine.展开更多
A carbon paste electrode（CPE） chemically modified with multiwall carbon nanotubes and ferrocene（FC） was used as a selective electrochemical sensor for the simultaneous determination of trace amounts of cysteamine...A carbon paste electrode（CPE） chemically modified with multiwall carbon nanotubes and ferrocene（FC） was used as a selective electrochemical sensor for the simultaneous determination of trace amounts of cysteamine（CA） and folic acid（FA）.This modified electrode showed very efficient electrocatalytic activity for the anodic oxidation of CA.The peak current of differential pulse voltammograms of CA and FA increased linearly with their concentration in the ranges of 0.7-200μmol/L CA and 5.0- 700μmol/L FA.The detection limits for CA and FA were 0.3μmol/L and 2.0μmoI/L,respectively.The diffusion coefficient（D） and transfer coefficient（α） of CA were also determined.These conditions are sufficient to allow determination of CA and FA both individually and simultaneously.展开更多
An efficient synthesis of 5-oxo-2,5-dihydro-3-furancarboxylate derivatives via reaction of dialkyl acetylenedicarboxylate with triphenylphosphine （Ph3P） in the presence of activated carbonyl compounds such as ethyl ...An efficient synthesis of 5-oxo-2,5-dihydro-3-furancarboxylate derivatives via reaction of dialkyl acetylenedicarboxylate with triphenylphosphine （Ph3P） in the presence of activated carbonyl compounds such as ethyl pyruvate, benzil, benzoylcyanide, biacetyle or N-alkylisatins is described.展开更多
Potassium fluoride doped natural zeolite was found to be an efficient and selective solid base catalyst for 1,4-Michael addition. The catalyst is easily prepared and the workup procedure simplified by simple filtratio...Potassium fluoride doped natural zeolite was found to be an efficient and selective solid base catalyst for 1,4-Michael addition. The catalyst is easily prepared and the workup procedure simplified by simple filtration.All products were obtained in high yields as well as short reaction times.展开更多
An efficient synthesis of methyl 4-hydroxy-6-oxo-1,6-dihydro-2-pyridine carboxylates is described.This involves three component reactions between primary alkyl amines,malonyl dichloride and methyl propiolates.
Potassium ferrate impregnated on montmorillonite is a mild,cheap,and non-toxic reagent for the iodination of phenols, including naphthol,aromatic amines,and heterocyclic substrates in fair to excellent yields by a sim...Potassium ferrate impregnated on montmorillonite is a mild,cheap,and non-toxic reagent for the iodination of phenols, including naphthol,aromatic amines,and heterocyclic substrates in fair to excellent yields by a simple isolation procedure.展开更多
文摘In this work,we describe a new strategy for the electrochemical determination of captopril（CA） using ferrocenemonocarboxylic acid as a mediator and multiwall carbon nanotubes as sensors in aqueous solution at pH 7.0.The diffusion coefficient（D）,and the kinetic parameters such as electron transfer coefficient（α）.and heterogeneous rate constant（kh）,for CA were also determined using electrochemical approaches.Under the optimized conditions,the electrocatalytic oxidation peak current of captopril showed two linear dynamic ranges with a detection limit of 0.3×10^-6 mol L^-1 captopril.The linear calibration range was 0.8×10^（-6） to 65×10^-6 mol L^-1 using cyclic voltammetry.Finally,this modified electrode was also examined as a selective,simple and precise new electrochemical sensor for the determination of captopril in real samples such as drug and patient human urine.
文摘A carbon paste electrode（CPE） chemically modified with multiwall carbon nanotubes and ferrocene（FC） was used as a selective electrochemical sensor for the simultaneous determination of trace amounts of cysteamine（CA） and folic acid（FA）.This modified electrode showed very efficient electrocatalytic activity for the anodic oxidation of CA.The peak current of differential pulse voltammograms of CA and FA increased linearly with their concentration in the ranges of 0.7-200μmol/L CA and 5.0- 700μmol/L FA.The detection limits for CA and FA were 0.3μmol/L and 2.0μmoI/L,respectively.The diffusion coefficient（D） and transfer coefficient（α） of CA were also determined.These conditions are sufficient to allow determination of CA and FA both individually and simultaneously.
文摘An efficient synthesis of 5-oxo-2,5-dihydro-3-furancarboxylate derivatives via reaction of dialkyl acetylenedicarboxylate with triphenylphosphine （Ph3P） in the presence of activated carbonyl compounds such as ethyl pyruvate, benzil, benzoylcyanide, biacetyle or N-alkylisatins is described.
文摘Potassium fluoride doped natural zeolite was found to be an efficient and selective solid base catalyst for 1,4-Michael addition. The catalyst is easily prepared and the workup procedure simplified by simple filtration.All products were obtained in high yields as well as short reaction times.
基金financial and spiritual support from the National Endowment for the Elite
文摘An efficient synthesis of methyl 4-hydroxy-6-oxo-1,6-dihydro-2-pyridine carboxylates is described.This involves three component reactions between primary alkyl amines,malonyl dichloride and methyl propiolates.
基金the Islamic Azad University of Qaemshahr for financial support
文摘Potassium ferrate impregnated on montmorillonite is a mild,cheap,and non-toxic reagent for the iodination of phenols, including naphthol,aromatic amines,and heterocyclic substrates in fair to excellent yields by a simple isolation procedure.
