Avaji Prakash Gouda, Kumar C H Vinod, Patil Sangamesh A, Shivananda K N, Nagaraju C
Department of Organic Chemistry, Indian Institute of Science, Bangalore 560012, Karnataka, India.
Eur J Med Chem. 2009 Sep;44(9):3552-9. doi: 10.1016/j.ejmech.2009.03.032. Epub 2009 Apr 5.
A macrocyclic hydrazone Schiff base was synthesized by reacting 1,4-dicarbonyl phenyl dihydrazide with 2,6-diformyl-4-methyl phenol and a series of metal complexes with this new Schiff base were synthesized by reaction with Co(II), Ni(II) and Cu(II) metal salts. The Schiff base and its complexes have been characterized by elemental analyses, IR, (1)H NMR, UV-vis, FAB mass, ESR spectra, fluorescence, thermal, magnetic and molar conductance data. The analytical data reveal that the Co(II), Ni(II) and Cu(II) complexes possess 2:1 metal-ligand ratios. All the complexes are non-electrolytes in DMF and DMSO due to their low molar conductance values. Infrared spectral data suggest that the hydrazone Schiff base behaves as a hexadentate ligand with NON NON donor sequence towards the metal ions. The ESR spectral data shows that the metal-ligand bond has considerable covalent character. The electrochemical behavior of the copper(II) complex was investigated by cyclic voltammetry. The Schiff base and its complexes have also been screened for their antibacterial (Escherichia coli, Staphylococcus aureus, Shigella dysentery, Micrococcus, Bacillus subtilis, Bacillus cereus and Pseudomonas aeruginosa) and antifungal activities (Aspergillus niger, Penicillium and Candida albicans) by MIC method. The brine shrimp bioassay was also carried out to study their in-vitro cytotoxic properties.
通过使1,4 - 二羰基苯基二酰肼与2,6 - 二甲酰基 - 4 - 甲基苯酚反应合成了一种大环腙席夫碱，并通过与Co(II)、Ni(II)和Cu(II)金属盐反应合成了一系列与这种新席夫碱的金属配合物。通过元素分析、红外光谱、(1)H核磁共振、紫外可见光谱、快原子轰击质谱、电子顺磁共振光谱、荧光光谱、热分析、磁性分析和摩尔电导率数据对席夫碱及其配合物进行了表征。分析数据表明，Co(II)、Ni(II)和Cu(II)配合物具有2:1的金属 - 配体比。由于其低摩尔电导率值，所有配合物在N,N - 二甲基甲酰胺和二甲基亚砜中均为非电解质。红外光谱数据表明，腙席夫碱对金属离子表现为具有NON NON供体序列的六齿配体。电子顺磁共振光谱数据表明，金属 - 配体键具有相当大的共价特征。通过循环伏安法研究了铜(II)配合物的电化学行为。还通过最小抑菌浓度法筛选了席夫碱及其配合物的抗菌活性（针对大肠杆菌、金黄色葡萄球菌、痢疾志贺氏菌、微球菌、枯草芽孢杆菌、蜡样芽孢杆菌和铜绿假单胞菌）和抗真菌活性（针对黑曲霉、青霉和白色念珠菌）。还进行了卤虫生物测定以研究它们的体外细胞毒性特性。
