The investigation of complexation of uranium with biological active ligands is vital for understanding uranium speciation in biosystems. A number of studies have been undertaken for investigating the complexation of u...The investigation of complexation of uranium with biological active ligands is vital for understanding uranium speciation in biosystems. A number of studies have been undertaken for investigating the complexation of uranium in its (VI) oxidation states but similar investigations pertaining to the interaction of uranium, in lower oxidation states, with biological ligands is scarce. The aim of the work is to bridge this gap and studies have been carried out to determine the coordination pattern of pyridine-3-carboxylic acid with uranium(IV). Semi-micro analysis, spectro-analytical techniques, magnetic susceptibility and cyclic voltammetry have been employed for the characterization of the synthesized complex.展开更多
A novel organotin complex [（n-Bu）3Sn（OCOC5H4NO）]n has been synthesized and characterized by elemental analysis, IR and ^1H NMR. The crystal structure has been determined by X-ray single-crystal diffraction. The cr...A novel organotin complex [（n-Bu）3Sn（OCOC5H4NO）]n has been synthesized and characterized by elemental analysis, IR and ^1H NMR. The crystal structure has been determined by X-ray single-crystal diffraction. The crystal belongs to monoclinic, space group P2 1/c with a = 8.982（2）, b = 17.908（4）, c = 13.219（3） A, β= 96.981（4）°, Z = 4, V= 2110.6（8） A^3, Dc = 1.347 g/cm^3, μ（MoKa） = 12.23 cm^-1, F（000） = 880, R = 0.0497 and wR = 0.1263. In the molecular structure of the title complex, the tin atoms are five-coordinated in a distorted trigonal bipyramidal geometry. A one-dimensional linear polymer is formed through an interaction between the O atoms of pyridine-3-carboxylic acid N-oxide and tin atoms of an adjacent molecule.展开更多
The copper（Ⅱ） complexes of pyridine-3-carboxylic acid （nicotinic acid） and pyridine-2-carboxylic acid （isonicotinic acid） were synthesized, and their structures were characterized by elemental analysis, infrare...The copper（Ⅱ） complexes of pyridine-3-carboxylic acid （nicotinic acid） and pyridine-2-carboxylic acid （isonicotinic acid） were synthesized, and their structures were characterized by elemental analysis, infrared spectrum, powder X-ray diffraction and so on. The results show that under experimental conditions, the ligands of synthesized copper nicotinate and copper isonicotinate are coordinated simultaneity with copper（Ⅱ） via the nitrogen of pyridine group and an oxygen of carboxylic acid group to form bidentate chelates. The crystal of copper nicotinate with two six-membered chelate rings belongs to monoclinic system, while that of copper isonicotinate having two five-membered chelate rings is of triclinic system. The tests show that the biological activities, such as the improvement of feed utilization, growth, anti-oxidation ability of organism and disease-resistant power, are different when copper nicotinate, copper inicotinate, copper-lysine chelate, copper-methionine chelate and copper sulphate are added in pig＇s feed, respectively. Due to its higher biological activity, less pollution and lower toxicity, copper nicotinate has wide potential applications as a feed additive.展开更多
文摘The investigation of complexation of uranium with biological active ligands is vital for understanding uranium speciation in biosystems. A number of studies have been undertaken for investigating the complexation of uranium in its (VI) oxidation states but similar investigations pertaining to the interaction of uranium, in lower oxidation states, with biological ligands is scarce. The aim of the work is to bridge this gap and studies have been carried out to determine the coordination pattern of pyridine-3-carboxylic acid with uranium(IV). Semi-micro analysis, spectro-analytical techniques, magnetic susceptibility and cyclic voltammetry have been employed for the characterization of the synthesized complex.
基金The project was supported by the National Natural Science Foundation of China (No. 20271025), the Natural Science Foundation of Shandong Province (No. Z2001B02) and the State Key Laboratory of Crystal Material
文摘A novel organotin complex [（n-Bu）3Sn（OCOC5H4NO）]n has been synthesized and characterized by elemental analysis, IR and ^1H NMR. The crystal structure has been determined by X-ray single-crystal diffraction. The crystal belongs to monoclinic, space group P2 1/c with a = 8.982（2）, b = 17.908（4）, c = 13.219（3） A, β= 96.981（4）°, Z = 4, V= 2110.6（8） A^3, Dc = 1.347 g/cm^3, μ（MoKa） = 12.23 cm^-1, F（000） = 880, R = 0.0497 and wR = 0.1263. In the molecular structure of the title complex, the tin atoms are five-coordinated in a distorted trigonal bipyramidal geometry. A one-dimensional linear polymer is formed through an interaction between the O atoms of pyridine-3-carboxylic acid N-oxide and tin atoms of an adjacent molecule.
基金Supported by the Natural Science Foundation of Fujian Province (B0510012) and the Science and Technology of Science Foundation of Fujian Education Department (JA04189)
文摘The copper（Ⅱ） complexes of pyridine-3-carboxylic acid （nicotinic acid） and pyridine-2-carboxylic acid （isonicotinic acid） were synthesized, and their structures were characterized by elemental analysis, infrared spectrum, powder X-ray diffraction and so on. The results show that under experimental conditions, the ligands of synthesized copper nicotinate and copper isonicotinate are coordinated simultaneity with copper（Ⅱ） via the nitrogen of pyridine group and an oxygen of carboxylic acid group to form bidentate chelates. The crystal of copper nicotinate with two six-membered chelate rings belongs to monoclinic system, while that of copper isonicotinate having two five-membered chelate rings is of triclinic system. The tests show that the biological activities, such as the improvement of feed utilization, growth, anti-oxidation ability of organism and disease-resistant power, are different when copper nicotinate, copper inicotinate, copper-lysine chelate, copper-methionine chelate and copper sulphate are added in pig＇s feed, respectively. Due to its higher biological activity, less pollution and lower toxicity, copper nicotinate has wide potential applications as a feed additive.
