Literature evidences reveal the affinity of ionic liquids for biomembranes that they are readily absorbed into the cell, resulting in a variety of biological effects, including broad antibacterial potential and anticancer activity. Recent research directions considered the ions of this class of compounds as a new choice of ligands in the synthesis of transition metal complexes for various applications. Based on this, the present work reports the synthesis, structural characterization, and in vitro antibacterial activities of a tetrahedral hexacationic Co(II) complex formed by coordinating with the cation of an ionic liquid, N-butyl-4,4-bipyridinium bis(trifluoromethylsulfonyl)amide ([C₄Bip][Tf₂N]). It has been demonstrated by the isolation and characterization of tetrakis-(N-butyl-4,4′-bipyridinium)cobalt(II)dichloride-tetrakis-(bis(trifluoromethylsulfonyl)amide, ([(C₄Bip)₄Co]Cl₂(Tf₂N)₄). The ligand and complex are characterized spectroscopically (¹H, ¹³C, and ¹⁹F NMR, ESI MS, ICP OES), and by CHNS elemental analysis, halide estimation, and conductivity studies. The antibacterial activities of the compounds against two bacteria, Klebsiella pneumoniae (K. pneumoniae) and Staphylococcus aureus (S. aureus), are screened using the agar well-diffusion method and were compared with a reference (gentamicin). The metal complex demonstrated better inhibition than the ionic liquid and the reference.

中文翻译：

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离子液体作为配体在合成新配位化合物中的非官能化阳离子及其生物活性的评估。

文献证据表明，离子液体对生物膜的亲和力很容易被细胞吸收，从而导致多种生物学效应，包括广泛的抗菌潜力和抗癌活性。最近的研究方向认为这类化合物的离子是用于各种应用的过渡金属配合物合成中配体的新选择。基于此，本工作报告了通过与离子液体N-丁基-4,4-联吡啶双（双-）的阳离子配位形成的四面体六阳离子Co（II）配合物的合成，结构表征和体外抗菌活性。三氟甲基磺酰基）酰胺（[C ₄ Bip] [Tf ₂N]）。通过四-（N-丁基-4,4'-联吡啶鎓）二氯化钴（II）-四-（双（三氟甲基磺酰基）酰胺，（[（C ₄ Bip）₄ Co] Cl ₂（Tf ₂ N）₄）。通过光谱（¹ H，¹³ C和¹⁹ F NMR，ESI MS，ICP OES）以及CHNS元素分析，卤化物估算和电导率研究对配体和配合物进行表征。针对两种细菌中，所述化合物的活性肺炎克雷伯氏菌（ķ。肺炎）和金黄色葡萄球菌（使用琼脂充分扩散的方法筛选金黄色葡萄球菌（S. aureus），并将其与参考品（庆大霉素）进行比较。与离子液体和参照物相比，金属络合物显示出更好的抑制作用。