Metal complexes of the 2,2'-(1,3-phenylenebis(diazene-2,1-diyl))bis(4-aminobenzoic acid) diazo ligand (H2L) derived from m-phenylenediamine and p-aminobenzoic acid were synthesized and characterized by different spectral, thermal, and analytical tools. The H2L ligand reacted with the metal ions Cr(III), Mn(II), Fe(III), Co(II), Ni(II), Cu(II), Zn(II), and Cd(II) as 1 : 1 stoichiometry. All complexes displayed an octahedral geometry according to the electronic and magnetic moment measurements. The IR spectra revealed the binding of the azo ligand to the metal ions via two azo nitrogen atoms and protonated carboxylate O in a neutral tetradentate manner. Both IR and 1H NMR spectra documented the involvement of the carboxylate group without proton displacement. The thermal studies pointed out that the complexes had higher thermal stability comparable with that of the free ligand. SEM images revealed the presence of the diazo ligand and its Cd(II) complex in a nanostructure form. The contact angle measurements proved that the Cd(II) complex can be considered as a superhydrophobic material. The molecular and electronic structure of H2L and [Cd(H2L)Cl2].H2O were optimized theoretically, and the quantum chemical parameters were calculated. The biological activities of the ligand, as well as its metal complexes, have been tested in vitro against some bacteria and fungi species. The results showed that all the tested compounds have significant biological activities with different sensitivity levels. The binding between H2L and its Cd(II) complex with receptors of the crystal structure of S. aureus (PDB ID: 3Q8U), crystal structure of protein phosphatase (PPZ1) of Candida albicans (PDB ID: 5JPE), receptors of breast cancer mutant oxidoreductase (PDB ID: 3HB5), and crystal structure of Escherichia coli (PDB ID: 3T88) was predicted and given in detail using molecular docking.

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纳米偶氮配体及其超疏水复合物：合成、表征、DFT、接触角、分子对接和抗菌研究

合成了衍生自间苯二胺和对氨基苯甲酸的 2,2'-(1,3-亚苯基双(二氮烯-2,1-二基))双(4-氨基苯甲酸)重氮配体 (H2L) 的金属配合物，并具有不同的光谱、热和分析工具。H2L 配体与金属离子 Cr(III)、Mn(II)、Fe(III)、Co(II)、Ni(II)、Cu(II)、Zn(II) 和 Cd(II) 反应为 1 : 1 化学计量。根据电子和磁矩测量，所有配合物都显示出八面体几何形状。红外光谱显示偶氮配体通过两个偶氮氮原子和质子化的羧酸盐 O 以中性四齿方式与金属离子结合。IR 和 1H NMR 光谱都记录了羧酸盐基团的参与，而没有质子置换。热研究指出，与游离配体相比，配合物具有更高的热稳定性。SEM 图像揭示了重氮配体及其纳米结构形式的 Cd(II) 配合物的存在。接触角测量证明 Cd(II) 配合物可以被认为是一种超疏水材料。理论优化了H2L和[Cd(H2L)Cl2].H2O的分子结构和电子结构，计算了量子化学参数。配体及其金属配合物的生物活性已在体外针对某些细菌和真菌物种进行了测试。结果表明，所有测试化合物都具有显着的生物活性，但灵敏度不同。H2L 与其 Cd(II) 复合物与金黄色葡萄球菌晶体结构受体之间的结合（PDB ID：