Metal complexes of novel Schiff base (HL) ligand, prepared via condensation of 4-aminoantipyrine and 2-aminophenol, are prepared. The ligand is characterized based on elemental analysis, mass, IR and (1)H NMR spectra. Metal complexes are reported and characterized based on elemental analyses, IR, (1)H NMR, solid reflectance, magnetic moment, molar conductance, ESR spectra and thermal analyses (TG, DTG and DTA). From the elemental analyses, 1:1 [M]:[ligand] complexes are prepared with the general formulae [M(L)Cl(H(2)O)(2)] x yH(2)O (M = Mn(II), Co(II), Ni(II), Cu(II), Zn(II) and Cd(II), y = 3-4), [Fe(L)Cl(2)(H(2)O)] x 3 H(2)O and [Th(L)Cl(H(2)O)(2)]Cl(2) x 3 H(2)O. The molar conductance data reveal that all the metal chelates are non-electrolytes (except Th(IV) complex, it is 2:1 electrolyte). IR spectra show that HL is coordinated to the metal ions in a uninegatively tridentate manner with NNO donor sites of the azomethine-N, amino N and deprotonated phenolic-O. From the magnetic and solid reflectance spectra, it is found that the geometrical structures of these complexes are octahedral. The thermal behaviour of these chelates shows that the hydrated complexes losses water molecules of hydration in the first step followed immediately by decomposition of the anions and ligand molecules in the subsequent steps. The activation thermodynamic parameters are calculated from the DTG curves using Coats-Redfern method. The synthesized ligand, in comparison to its metal complexes is screened for its antibacterial activity against bacterial species, Escherichia coli, Pseudomonas putida, Exiguobacterium acetylicum and Bacillus simplex. 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▼
机译：制备通过4-氨基安替比林和2-氨基苯酚缩合制备的新型席夫碱（HL）配体的金属配合物。基于元素分析，质量，IR和（1）H NMR光谱对配体进行表征。根据元素分析，IR，（1）H NMR，固体反射率，磁矩，摩尔电导，ESR光谱和热分析（TG，DTG和DTA）对金属配合物进行了报道和表征。从元素分析中，以通式[M（L）Cl（H（2）O）（2）] x yH（2）O（M = Mn（ II），Co（II），Ni（II），Cu（II），Zn（II）和Cd（II），y = 3-4），[Fe（L）Cl（2）（H（2）O ）] x 3 H（2）O和[Th（L）Cl（H（2）O）（2）] Cl（2）x 3 H（2）O。摩尔电导数据显示所有金属螯合物都是非电解质（除了Th（IV）络合物，它是2：1电解质）。红外光谱表明，HL与偶氮甲胺-N，氨基N和去质子化酚-O的NNO供体位点以一致的三齿方式与金属离子配位。从磁和固体反射光谱，发现这些络合物的几何结构是八面体的。这些螯合物的热行为表明，水合配合物在第一步中损失了水合水分子，随后在随后的步骤中立即分解了阴离子和配体分子。使用Coats-Redfern方法从DTG曲线计算出活化热力学参数。相对于其金属配合物，对合成的配体针对细菌，大肠杆菌，恶臭假单胞菌，乙状芽孢杆菌和单纯芽孢杆菌的抗菌活性进行筛选。活性数据表明，金属配合物比针对一种或多种细菌的母体席夫碱配体更有效/更具抗菌性。
展开▼
