Synthesis, structural characterization and antibacterial activity of diorganotin(IV) complexes with ONO tridentate Schiff bases containing pyridine ring
organotin(IV) complexes, were obtained by reaction of SnR2Cl2 (R = Ph, Me, Bu) with ONO donor Schiffbases. The synthesized complexes have been investigated by elemental analysis and IR, 1H NMR, and 119Sn NMR spectroscopy. These data show that the Schiff base acts as a tridentate dianionic ligand and coordinates via the imine nitrogen and two oxygen atoms. The X-ray crystallography of complex 4 shows
通过SnR 2 Cl 2(R = Ph,Me,Bu)与ONO供体席夫碱的反应获得了五种有机锡(IV)配合物。合成的配合物已通过元素分析和IR,1 H NMR和119 Sn NMR光谱进行了研究。这些数据表明,席夫碱起着三齿双阴离子配体的作用,并通过亚胺氮和两个氧原子进行配位。配合物4的X射线晶体学显示该分子的二聚体结构。在体外的席夫碱及其配合的抗菌活性已经对革兰氏阳性(评估枯草芽孢杆菌和金黄色葡萄球菌)和革兰氏阴性(大肠埃希氏菌和铜绿假单胞菌)细菌,并与标准抗菌药物进行比较。
Synthesis, solvatochromaticity and bioactivities of some transition metal complexes with 2-(R-benzylideneamino)-pyridin-3-ol Schiff base derivatives
作者:I.S. Ahmed、M.A. Kassem
DOI:10.1016/j.saa.2010.03.026
日期:2010.10
New four Schiff bases are prepared by condensation of 2-amino-pyridin-3-ol with 3, 4-dihydroxy-benzaldehyde (I), 2-hydroxybenzaldehyde (II), 5-bromo-2-hydroxybenzaldehyde (III), and 4-dimethylaminobenzaldehyde (IV). The structures of these compounds are characterized based on elemental analyses (C, H, N), IR and H-1 NMR. Also, the electronic absorption spectra are recorded in organic solvents of different polarity. The solvents are selected to be covered a wide range of parameters (refractive index, dielectric constant and hydrogen bonding capacity). The UV-vis absorption spectra of Schiff base compounds are investigated in aqueous buffer solutions of varying pH and utilized for the determination of ionization constant, pK(a) and activation free energy. Delta G* of the ionization process. The biological activity against bacterial species and fungi as microorganisms representing different microbial categories such as (two Gram-negative bacteria, Eschericha coli and Agrobacterium sp.),three Gram-positive bacteria (Staphylococcus aureus, Bacillus subtlus and Bacillus megatherium), yeast (Candida albicans), and fungi (Aspergillus niger) were studied. (C) 2010 Published by Elsevier B.V.