Three mononuclear copper(II) complexes, viz. [CuL1] (1), [CuL2] (2), [CuL3] (3), and one nickel(II) complex, viz.[NiL3] (4) where H2L1 = 3,3′-{(methylazanediyl)bis[(propane-3,1-diyl)azanylylidenemethanylylidene]}bis(4-bromophenol), H2L2 = 2,2′-[1,2-phenylenebis(azanylylidenemethanylylidene)]bis(4-bromophenol) and H2L3 = 3,3′-{(methylazanediyl)bis[(propane-3,1-diyl)azanylylidenemethanylylidene]}bis(4,6-dibromophenol), have been prepared. The syntheses have been carried out by the reaction of copper perchlorate (for 1–3) or nickel perchlorate (for 4) with the corresponding Schiff base in the molar ratio of 1:1. The complexes have been characterized by several physicochemical techniques including single-crystal X-ray diffraction. Structural studies reveal that the complexes 1, 3 and 4 adopt distorted trigonal bipyramidal structures, while 2 adopts a distorted square planar geometry. The antibacterial activity of the complexes and the constituent Schiff bases has been tested against two Gram(+) and two Gram(−) bacteria.

中文翻译：

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铜(II)镍(II)四种单核席夫碱配合物的合成、晶体结构及抗菌活性

三个单核铜 (II) 配合物，即。[CuL1] (1)、[CuL2] (2)、[CuL3] (3) 和一种镍 (II) 络合物，即 [NiL3] (4) 其中 H2L1 = 3,3'-{(methylazanediyl)bis [(propane-3,1-diyl)azanylylidenemethanylylidene]}bis(4-bromophenol), H2L2 = 2,2'-[1,2-phenylenebis(azanylylidenemethanylylidene)]bis(4-bromophenol) and H2L3 = 3,3' -{(methylazanediyl)bis[(propane-3,1-diyl)azanylylidenemethanylylidene]}双(4,6-dibromophenol)，已制备。合成是通过高氯酸铜（1-3）或高氯酸镍（4）与相应的希夫碱以 1:1 的摩尔比反应进行的。这些配合物已通过多种物理化学技术进行表征，包括单晶 X 射线衍射。结构研究表明配合物1、3和4采用扭曲的三角双锥结构，而2采用扭曲的方形平面几何。复合物和组成希夫碱的抗菌活性已针对两种革兰氏 (+) 和两种革兰氏 (-) 细菌进行了测试。