A novel, simple approach to the synthesis of macrocyclic Schiff base ligand resulted from the condensation of bisaldehyde and ethylenediamine was prepared (7, 8, 15, 16, 17, 18-hexahydrodibenzo (a, g) (14) annulene) (...A novel, simple approach to the synthesis of macrocyclic Schiff base ligand resulted from the condensation of bisaldehyde and ethylenediamine was prepared (7, 8, 15, 16, 17, 18-hexahydrodibenzo (a, g) (14) annulene) (L) and its complexes were synthesized and characterized using different physicochemical studies as elemental analysis, FT-IR, 1H NMR, conductivity, magnetic properties, thermal analysis, and their biological activities. The spectroscopic data of the complexes suggest their 1:1 complexe structures which are investigated by elemental analysis, FT-IR, 1H NMR, conductivity, magnetic properties, thermal analysis, and their biological activities. The spectroscopic studies suggested the octahedral structure for the all complexes. The spectroscopic data of the complexes suggest their structure in which (N2O2) group act as a tetradentate ligand and two chlorides as monodentate ligands. Also electronic spectra and magnetic susceptibility measurements indicate octahedral structure of these complexes. The synthesized Schiff base and its metal complexes also were screened for their antibacterial and antifungal activity. Here we report the effect of a neutral chelating ligand on the complexation with iron to determine it in different types of natural water using recovery test. The activity data show that the metal complexes to be more potent/ antibacterial than the parent Schiff base ligand against one or more bacterial species.展开更多
A series of novel heteronuclear Ln( Ⅲ)-Cu( Ⅱ) complexes with noncyclic polyether-amino acid Schiff base were synthesized. The general formula is [LnCu2H2TALY)(NO3)5](NO3)2·nH2O (Ln= La, Nd, Sm, Gd, n = 4;Ln= Yb...A series of novel heteronuclear Ln( Ⅲ)-Cu( Ⅱ) complexes with noncyclic polyether-amino acid Schiff base were synthesized. The general formula is [LnCu2H2TALY)(NO3)5](NO3)2·nH2O (Ln= La, Nd, Sm, Gd, n = 4;Ln= Yb, Y, n = 3), where H2TALY = tetraglycol aldehyde bis-lysine Schiff base. It is the first time to report the synthetic method for this new Cu(Ⅱ) complexes and Ln( Ⅲ)-Cu( Ⅱ) heteronuclear complexes. The complexes were characterized by elemental analysis, IR spectra, TG-DTA, magnetic susceptibility, and especially by a 500 MHz NMR spectrometer for 2D-COSY NMR. Coordination mechanism and structures of complexes have been suggested as well. Of particular interest is the potential that the novel complexes obtained may be used as a catalyst, which prompted us to investigate them. It shows 100% conversion with the viscosity-average molecular weight 120 000 for the polymerization of methyl methacrylate (MMA) without addition of any cocatalyst. Furthermore, the complexes with such aliphatic Schiff bases can be used as a good catalyst, which has been confirmed and discussed here. They may be a new kind of catalyst system with the above speciality.展开更多
Owing to its two unsymmetrical-NH2 groups sited on different terminals, 2, 6-diaminocaproic acid (lysine) was used as a reactant for synthesizing a novel unsymmetrical Schiff base with salicylaldehyde on one side and ...Owing to its two unsymmetrical-NH2 groups sited on different terminals, 2, 6-diaminocaproic acid (lysine) was used as a reactant for synthesizing a novel unsymmetrical Schiff base with salicylaldehyde on one side and ovanillin on the other for the first time. It is a new way to synthesize such a special unsymmetrical Schiff base. It is named “hetero bis-Schiff base” for distinguishing it from others. The synthesis method, formation mechanism as well as twelve new lanthaniHe complexes with the above ligand are reported and discussed herein. They were characterized by elementary analysis, molar conductivity, IR-spectra and especially by1H and13C NMR spectra. The results obtained may provide a new promising method for synthesizing similar unsymmetrical Schiff bases and their complexes.展开更多
A novel dinuclear copper complex with tetraglycol aldehyde-phenylalanineSchiff base has been synthesized. It was characterized and formulated as [Cu_2L(NO_3)]NO_3 byelemental analysis, magnetic susceptibility, TG-DTA,...A novel dinuclear copper complex with tetraglycol aldehyde-phenylalanineSchiff base has been synthesized. It was characterized and formulated as [Cu_2L(NO_3)]NO_3 byelemental analysis, magnetic susceptibility, TG-DTA, IR, EPR and ~1H NMR spectra. The obtainedcomplex can be used as a good catalyst for the polymerization of methyl methacrylate (MMA). Theoptimum polymerization conditions are: MMA/catalyst = 500 (molar ratio); [catalyst] =7.5x10^(-3)mol·L^(-1); dioxane as solvent; 80℃; 6 h. Polymethyl methacrylate (PMMA) with 80%conversion, 7.2x10^5 viscosity-average molecular weight and 60.5% syndiotacticity was obtained. Thiscomplex has also been shown to play an important role in scavenging O_2^-.展开更多
A novel Schiff base (TAMET) was synthesized by the condensation of tetraglycol aldehyde with methionine and a mild oxidant CrO3. (C5H5N)2 was selected for the reaction. Seven new rare earth complexes with this Schiff ...A novel Schiff base (TAMET) was synthesized by the condensation of tetraglycol aldehyde with methionine and a mild oxidant CrO3. (C5H5N)2 was selected for the reaction. Seven new rare earth complexes with this Schiff base have been synthesized and characterized by elemental analysis, TG-DTA, molar Conductivity, magnetic susceptibility and IR, especially 1H NMR spectra. Information was obtained from reflectance spectra and the coordination of sulfur atom to rare earths was discussed. The experimental results show that these compounds have some biological activity and could dispose of O2?-.展开更多
A novel ligand, 1-(4-methoxybenzylidene)-4-methylthiosemicarbazone (MBT) derived from 4-methoxybenzaldehyde was synthesized and characterized by spectroscopic methods (IR, 1H NMR, 13C NMR), single crystal X-ray diffra...A novel ligand, 1-(4-methoxybenzylidene)-4-methylthiosemicarbazone (MBT) derived from 4-methoxybenzaldehyde was synthesized and characterized by spectroscopic methods (IR, 1H NMR, 13C NMR), single crystal X-ray diffraction technique and physical means. MBT showed antibacterial activity in vitro with MICs of 64 μg/mL (a strain of Salmonella typhi (ATCC 6539)), 128 μg/mL (Salmonella typhi), 64 μg/mL (Salmonella paratyphi A), 128 μg/mL (Salmonella paratyphi B) and 64 μg/mL (Salmonella typhimurium). The results showed that MBT demonstrated moderate in vitro antibacterial activity against a strain of Salmonella typhi (ATCC 6539), Salmonella paratyphi A, and Salmonella typhimurium, indicating its promise as a possible lead for the discovery of antibacterial drugs.展开更多
文摘A novel, simple approach to the synthesis of macrocyclic Schiff base ligand resulted from the condensation of bisaldehyde and ethylenediamine was prepared (7, 8, 15, 16, 17, 18-hexahydrodibenzo (a, g) (14) annulene) (L) and its complexes were synthesized and characterized using different physicochemical studies as elemental analysis, FT-IR, 1H NMR, conductivity, magnetic properties, thermal analysis, and their biological activities. The spectroscopic data of the complexes suggest their 1:1 complexe structures which are investigated by elemental analysis, FT-IR, 1H NMR, conductivity, magnetic properties, thermal analysis, and their biological activities. The spectroscopic studies suggested the octahedral structure for the all complexes. The spectroscopic data of the complexes suggest their structure in which (N2O2) group act as a tetradentate ligand and two chlorides as monodentate ligands. Also electronic spectra and magnetic susceptibility measurements indicate octahedral structure of these complexes. The synthesized Schiff base and its metal complexes also were screened for their antibacterial and antifungal activity. Here we report the effect of a neutral chelating ligand on the complexation with iron to determine it in different types of natural water using recovery test. The activity data show that the metal complexes to be more potent/ antibacterial than the parent Schiff base ligand against one or more bacterial species.
基金Project supported by the National Natural Science Foundation of China (Grant No. 29671026)Natural Science Foundation of Zhejiang Province (Grant No. 296062)the Laboratory of MRAMP (Grant No. 971502)
文摘A series of novel heteronuclear Ln( Ⅲ)-Cu( Ⅱ) complexes with noncyclic polyether-amino acid Schiff base were synthesized. The general formula is [LnCu2H2TALY)(NO3)5](NO3)2·nH2O (Ln= La, Nd, Sm, Gd, n = 4;Ln= Yb, Y, n = 3), where H2TALY = tetraglycol aldehyde bis-lysine Schiff base. It is the first time to report the synthetic method for this new Cu(Ⅱ) complexes and Ln( Ⅲ)-Cu( Ⅱ) heteronuclear complexes. The complexes were characterized by elemental analysis, IR spectra, TG-DTA, magnetic susceptibility, and especially by a 500 MHz NMR spectrometer for 2D-COSY NMR. Coordination mechanism and structures of complexes have been suggested as well. Of particular interest is the potential that the novel complexes obtained may be used as a catalyst, which prompted us to investigate them. It shows 100% conversion with the viscosity-average molecular weight 120 000 for the polymerization of methyl methacrylate (MMA) without addition of any cocatalyst. Furthermore, the complexes with such aliphatic Schiff bases can be used as a good catalyst, which has been confirmed and discussed here. They may be a new kind of catalyst system with the above speciality.
基金Project supported by the National Natural Science Foundation of China (Grant No. 29671026)the Natural Science Foundation of Zhejiang Province (Grant No. 296062)the Laboratory of MRAMP (Grant No. 971502)
文摘Owing to its two unsymmetrical-NH2 groups sited on different terminals, 2, 6-diaminocaproic acid (lysine) was used as a reactant for synthesizing a novel unsymmetrical Schiff base with salicylaldehyde on one side and ovanillin on the other for the first time. It is a new way to synthesize such a special unsymmetrical Schiff base. It is named “hetero bis-Schiff base” for distinguishing it from others. The synthesis method, formation mechanism as well as twelve new lanthaniHe complexes with the above ligand are reported and discussed herein. They were characterized by elementary analysis, molar conductivity, IR-spectra and especially by1H and13C NMR spectra. The results obtained may provide a new promising method for synthesizing similar unsymmetrical Schiff bases and their complexes.
基金This work was supported by the National Natural Science Foundation of China (Grant No.29671026) the Natural Science Foundation of Zhejiang Province, China (Grant No. 202033).
文摘A novel dinuclear copper complex with tetraglycol aldehyde-phenylalanineSchiff base has been synthesized. It was characterized and formulated as [Cu_2L(NO_3)]NO_3 byelemental analysis, magnetic susceptibility, TG-DTA, IR, EPR and ~1H NMR spectra. The obtainedcomplex can be used as a good catalyst for the polymerization of methyl methacrylate (MMA). Theoptimum polymerization conditions are: MMA/catalyst = 500 (molar ratio); [catalyst] =7.5x10^(-3)mol·L^(-1); dioxane as solvent; 80℃; 6 h. Polymethyl methacrylate (PMMA) with 80%conversion, 7.2x10^5 viscosity-average molecular weight and 60.5% syndiotacticity was obtained. Thiscomplex has also been shown to play an important role in scavenging O_2^-.
基金Project supported by the National Natural Science Foundation of China (No. 29671026)the Natural Science Foundation of Zhejiang Province (No. 296062)the State Key Laboratory of Magnetic Resonance and Atomic and Molecular Physics (No. 971502)
文摘A novel Schiff base (TAMET) was synthesized by the condensation of tetraglycol aldehyde with methionine and a mild oxidant CrO3. (C5H5N)2 was selected for the reaction. Seven new rare earth complexes with this Schiff base have been synthesized and characterized by elemental analysis, TG-DTA, molar Conductivity, magnetic susceptibility and IR, especially 1H NMR spectra. Information was obtained from reflectance spectra and the coordination of sulfur atom to rare earths was discussed. The experimental results show that these compounds have some biological activity and could dispose of O2?-.
文摘A novel ligand, 1-(4-methoxybenzylidene)-4-methylthiosemicarbazone (MBT) derived from 4-methoxybenzaldehyde was synthesized and characterized by spectroscopic methods (IR, 1H NMR, 13C NMR), single crystal X-ray diffraction technique and physical means. MBT showed antibacterial activity in vitro with MICs of 64 μg/mL (a strain of Salmonella typhi (ATCC 6539)), 128 μg/mL (Salmonella typhi), 64 μg/mL (Salmonella paratyphi A), 128 μg/mL (Salmonella paratyphi B) and 64 μg/mL (Salmonella typhimurium). The results showed that MBT demonstrated moderate in vitro antibacterial activity against a strain of Salmonella typhi (ATCC 6539), Salmonella paratyphi A, and Salmonella typhimurium, indicating its promise as a possible lead for the discovery of antibacterial drugs.
