<div style="text-align:justify;"> <span style="font-family:Verdana;">The aim of this work is to synthesize, characterize and evaluate the biological activity of 1,4-naphthoquinone deriv...<div style="text-align:justify;"> <span style="font-family:Verdana;">The aim of this work is to synthesize, characterize and evaluate the biological activity of 1,4-naphthoquinone derivatives ligands and their metal—Co(II), Ni(II) and Cu(II) chelates. Continuing our work with another derivatives of 1,4-naphthoquinone ligands, this work had been constructed for synthesis of new ligands derived from 1,4-naphthoquinone such as 3-thioacetyl-2-amino-1,4-naphthoquinone and 2-benzoyl-3-amino-1,4-naphthoquinone (L<span style="white-space:nowrap;"><sup>1</sup></span>-L<span style="white-space:nowrap;"><sup>2</sup></span>) which characterized on the basis of elemental analysis, electronic, IR, mass, <span style="white-space:nowrap;"><sup>1</sup></span>H-NMR spectral data. The synthesized ligands have been carried out to achieve the coordination behavior towards bi-valent metal ions like cobalt, nickel and copper. The solid chelates of the different ligands were prepared and subjected to analytical techniques such as elemental analyses, spectroscopic techniques including mass, <span style="white-space:nowrap;"><sup>1</sup></span>H-NMR, and IR spectroscopy, and thermal analyses techniques. The chelates were found to have octahedral geometry. The biological activity of the prepared ligands and their binary metals complexes were also screened against different antifungal and antibacterial organisms.</span> </div>展开更多
<div style="text-align:justify;"> <span style="font-family:Verdana;">The aim of this work is to synthesize, characterize and evaluate the biological activity of 2-acetyl and 2-formyl-3-...<div style="text-align:justify;"> <span style="font-family:Verdana;">The aim of this work is to synthesize, characterize and evaluate the biological activity of 2-acetyl and 2-formyl-3-amino-1,4-naphthoquinone (L<span style="white-space:nowrap;"><sup>1</sup></span> - L<span style="white-space:nowrap;"><sup>2</sup></span>) and their metal-Co(II), Ni(II) and Cu(II) chelates. The newly chelates were characterized by elemental analysis, IR, mass and <span style="white-space:nowrap;"><sup>1</sup></span>HNMR spectra, thermogravimetric analysis (TGA) and biological activity. The antibacterial and antifungal activities of the ligands and its metal complexes were screened against bacterial species (<span style="white-space:nowrap;"><i>Staphylococcus aureus, Bacillus subtilis and Escherichia coli</i></span>) and fungi (<span style="white-space:nowrap;"><i>Candida albicans</i></span>). Ampicillin and amphotericin were used as references for antibacterial and antifungal studies. The activity data show that the metal complexes have a promising biological activity comparable with parent free ligand against bacterial and fungal species.</span> </div>展开更多
Schiff bases are the most widely used organic compounds. They have been shown to exhibit a broad range of biological activities, including antifungal, antibacterial, antimalarial, antiproliferative, anti-inflammatory,...Schiff bases are the most widely used organic compounds. They have been shown to exhibit a broad range of biological activities, including antifungal, antibacterial, antimalarial, antiproliferative, anti-inflammatory, antiviral, and antipyretic properties. This review summarizes the synthesis and biological activities of Schiff bases and their complexes.展开更多
This work involved the synthesis of two Schiff base derivatives of cefotaxime antibiotic (CFX) namely: [sodium3-(acetoxymethyl)-7-((Z)-2-(methoxyimino)-2-(2-((E)-2–oxoindolin-3-ylide-neamino) thiazol-4-yl)acetamido)-...This work involved the synthesis of two Schiff base derivatives of cefotaxime antibiotic (CFX) namely: [sodium3-(acetoxymethyl)-7-((Z)-2-(methoxyimino)-2-(2-((E)-2–oxoindolin-3-ylide-neamino) thiazol-4-yl)acetamido)-8-oxo-5-thia-1-azabicyclo[4.2.0]oct-2-ene-2-carboxylate]. (0.5) Methanol (LI) and [sodium3-(acetoxymethyl)-7-((2Z)-2-(2-(4-dimethylamino) benzylideneamino) thiazol-4-yl)-2-(methoxyimino)acetamido)-8-oxo-5-thia-1-azabicyclo [4.2.0] oct-2-ene-2-carboxylate]. (0.5) Methanol (LII) from the condensation reaction of the antibiotic with 1H-Indole-2,3-dione(isatin) and -N, N-dimethyl amino benzaldehyde respectively. Metal complexes of the two Schiff base ligands with Co(II), Ni(II), Cu(II), Cd(II), Pd(II) and Pt(IV) ions were prepared by reacting each ligand with the metal salts in refluxing ethanol. The chemical structures of the two ligands as well as the stereo-chemical structures and geometries of the studied metal complexes were suggested depending the results obtained from CHN and TG analysis, NMR, FTIR, and atomic absorption spectrophotometry, electronic spectra, magnetic moments and conductivity measurements. The mole ratio of the ligands to the metal ion was 1:1 with tridentate bonding behaviors of the coordinating ligands with the metal ions.展开更多
The metal complexes of norfloxacin were prepared, and their structures were characterized using spectroscopic techniques like IR, 1H NMR, UV, atomic absorption, and CHN analysis. The solubility, melting point, and con...The metal complexes of norfloxacin were prepared, and their structures were characterized using spectroscopic techniques like IR, 1H NMR, UV, atomic absorption, and CHN analysis. The solubility, melting point, and conductance measurements were also performed. These studies suggested that norfloxacin formed complexes with the metals utilizing carbonyl oxygen atom of the ring and carboxylic group oxygen atom. The antibacterial activities of these metal complexes against 14 different Gram-positive and Gram-negative microorganisms were studied by the disk susceptibility method. It was observed that the complexes of norfloxacin with magnesium, calcium, cobalt, nickel, and copper showed improved activity compared with the stated drug.展开更多
Five new transition metal complexes [Cu(HL)2(H20)2] (1), [Cu(HL)z(phen)] (2), [Cu(HL)2(H20)]2(4,4′-bipy) (3), [Zn(HL)2(HzO)2].(4,4′-bipy) (4), [Ag(HL)(4,4′-bipy)]n (5), (H2L=5-chl...Five new transition metal complexes [Cu(HL)2(H20)2] (1), [Cu(HL)z(phen)] (2), [Cu(HL)2(H20)]2(4,4′-bipy) (3), [Zn(HL)2(HzO)2].(4,4′-bipy) (4), [Ag(HL)(4,4′-bipy)]n (5), (H2L=5-chloro-l-phenyl-lH-pyrazole-3,4-dicarboxylic acid, phen=1,10-phenanthroline; 4,4′-bipy = 4,4′bipyridine) have been synthesized and characterized. Complexes 1, 2 and 4 exhibit monomeric structures, 3 shows a dinuclear structure, 5 displays 1D chain structure, and all extend to 3D supramolecular network via rich hydrogen bonds. Complexes 1, 2, 3, 5 comprise single helical chains, while complex 4 generates quadruple-stranded helical chains. Furthermore, the antibacterial activities of the titled complexes against bacterial species, three Gram positive bacteria (Staphylococcus aureus, Bacillus subtilis and Candida albicans) and two Gram negative bacteria (Escherichia coli and Pseudomonas aeruginosa) were stud-ied and compared to the activities of free ligands by using the microdilution method.展开更多
文摘<div style="text-align:justify;"> <span style="font-family:Verdana;">The aim of this work is to synthesize, characterize and evaluate the biological activity of 1,4-naphthoquinone derivatives ligands and their metal—Co(II), Ni(II) and Cu(II) chelates. Continuing our work with another derivatives of 1,4-naphthoquinone ligands, this work had been constructed for synthesis of new ligands derived from 1,4-naphthoquinone such as 3-thioacetyl-2-amino-1,4-naphthoquinone and 2-benzoyl-3-amino-1,4-naphthoquinone (L<span style="white-space:nowrap;"><sup>1</sup></span>-L<span style="white-space:nowrap;"><sup>2</sup></span>) which characterized on the basis of elemental analysis, electronic, IR, mass, <span style="white-space:nowrap;"><sup>1</sup></span>H-NMR spectral data. The synthesized ligands have been carried out to achieve the coordination behavior towards bi-valent metal ions like cobalt, nickel and copper. The solid chelates of the different ligands were prepared and subjected to analytical techniques such as elemental analyses, spectroscopic techniques including mass, <span style="white-space:nowrap;"><sup>1</sup></span>H-NMR, and IR spectroscopy, and thermal analyses techniques. The chelates were found to have octahedral geometry. The biological activity of the prepared ligands and their binary metals complexes were also screened against different antifungal and antibacterial organisms.</span> </div>
文摘<div style="text-align:justify;"> <span style="font-family:Verdana;">The aim of this work is to synthesize, characterize and evaluate the biological activity of 2-acetyl and 2-formyl-3-amino-1,4-naphthoquinone (L<span style="white-space:nowrap;"><sup>1</sup></span> - L<span style="white-space:nowrap;"><sup>2</sup></span>) and their metal-Co(II), Ni(II) and Cu(II) chelates. The newly chelates were characterized by elemental analysis, IR, mass and <span style="white-space:nowrap;"><sup>1</sup></span>HNMR spectra, thermogravimetric analysis (TGA) and biological activity. The antibacterial and antifungal activities of the ligands and its metal complexes were screened against bacterial species (<span style="white-space:nowrap;"><i>Staphylococcus aureus, Bacillus subtilis and Escherichia coli</i></span>) and fungi (<span style="white-space:nowrap;"><i>Candida albicans</i></span>). Ampicillin and amphotericin were used as references for antibacterial and antifungal studies. The activity data show that the metal complexes have a promising biological activity comparable with parent free ligand against bacterial and fungal species.</span> </div>
文摘Schiff bases are the most widely used organic compounds. They have been shown to exhibit a broad range of biological activities, including antifungal, antibacterial, antimalarial, antiproliferative, anti-inflammatory, antiviral, and antipyretic properties. This review summarizes the synthesis and biological activities of Schiff bases and their complexes.
文摘This work involved the synthesis of two Schiff base derivatives of cefotaxime antibiotic (CFX) namely: [sodium3-(acetoxymethyl)-7-((Z)-2-(methoxyimino)-2-(2-((E)-2–oxoindolin-3-ylide-neamino) thiazol-4-yl)acetamido)-8-oxo-5-thia-1-azabicyclo[4.2.0]oct-2-ene-2-carboxylate]. (0.5) Methanol (LI) and [sodium3-(acetoxymethyl)-7-((2Z)-2-(2-(4-dimethylamino) benzylideneamino) thiazol-4-yl)-2-(methoxyimino)acetamido)-8-oxo-5-thia-1-azabicyclo [4.2.0] oct-2-ene-2-carboxylate]. (0.5) Methanol (LII) from the condensation reaction of the antibiotic with 1H-Indole-2,3-dione(isatin) and -N, N-dimethyl amino benzaldehyde respectively. Metal complexes of the two Schiff base ligands with Co(II), Ni(II), Cu(II), Cd(II), Pd(II) and Pt(IV) ions were prepared by reacting each ligand with the metal salts in refluxing ethanol. The chemical structures of the two ligands as well as the stereo-chemical structures and geometries of the studied metal complexes were suggested depending the results obtained from CHN and TG analysis, NMR, FTIR, and atomic absorption spectrophotometry, electronic spectra, magnetic moments and conductivity measurements. The mole ratio of the ligands to the metal ion was 1:1 with tridentate bonding behaviors of the coordinating ligands with the metal ions.
文摘The metal complexes of norfloxacin were prepared, and their structures were characterized using spectroscopic techniques like IR, 1H NMR, UV, atomic absorption, and CHN analysis. The solubility, melting point, and conductance measurements were also performed. These studies suggested that norfloxacin formed complexes with the metals utilizing carbonyl oxygen atom of the ring and carboxylic group oxygen atom. The antibacterial activities of these metal complexes against 14 different Gram-positive and Gram-negative microorganisms were studied by the disk susceptibility method. It was observed that the complexes of norfloxacin with magnesium, calcium, cobalt, nickel, and copper showed improved activity compared with the stated drug.
基金This work was supported by the National Natural Science Foundation of China (Nos. 20961007 and 21264011), the Aviation Fund (No. 2010ZF56023) and the Young Scientists Program of Jiangxi Province (No. 2008DQ00600).
文摘Five new transition metal complexes [Cu(HL)2(H20)2] (1), [Cu(HL)z(phen)] (2), [Cu(HL)2(H20)]2(4,4′-bipy) (3), [Zn(HL)2(HzO)2].(4,4′-bipy) (4), [Ag(HL)(4,4′-bipy)]n (5), (H2L=5-chloro-l-phenyl-lH-pyrazole-3,4-dicarboxylic acid, phen=1,10-phenanthroline; 4,4′-bipy = 4,4′bipyridine) have been synthesized and characterized. Complexes 1, 2 and 4 exhibit monomeric structures, 3 shows a dinuclear structure, 5 displays 1D chain structure, and all extend to 3D supramolecular network via rich hydrogen bonds. Complexes 1, 2, 3, 5 comprise single helical chains, while complex 4 generates quadruple-stranded helical chains. Furthermore, the antibacterial activities of the titled complexes against bacterial species, three Gram positive bacteria (Staphylococcus aureus, Bacillus subtilis and Candida albicans) and two Gram negative bacteria (Escherichia coli and Pseudomonas aeruginosa) were stud-ied and compared to the activities of free ligands by using the microdilution method.