Three mononuclear coordination complexes of 1-butyl-2-((5-methyl-1H-pyrazol-3-yl)methyl)-1H-benzimidazole (L), namely [CoL]Cl₂ (C1), [Co₂L₂]Cl₂·H₂O (C2) and [Zn₂L₂]Cl₂ (C3), have been synthesized and characterized spectroscopically. Their single-crystal X-ray diffraction analysis revealed that C1 and C2 display pseudopolymorphism. The presence of N–H⋯Cl and C–H⋯Cl hydrogen bonding in the crystal structure of C1 and C3 assists the formation of a 2D hydrogen bonded sheet and orthogonal packing [2D sheet + a pair of 1D chains], respectively, leading to supramolecular structures. A combination of N–H⋯Cl, C–H⋯Cl, O–H⋯Cl, and C–H⋯O interactions results however in a 2D corrugated hydrogen bonded sheet with inclusion of water molecules in C2. Hirshfeld surface analysis confirms that hydrogen bonding and π-stacking contacts stabilize the crystal structures. These metal complexes display good performance towards their antimicrobial activity against Escherichia coli, Pseudomonas aeruginosa, and Staphylococcus aureus. In particular a normalized minimum inhibitory concentration as low as 6.25 μg mL⁻¹ for the bacterial strains was recorded for C2. Its structure–bioactivity correlation is discussed in detail.

中文翻译：

---

具有显着抗菌活性的Co（II）和Zn（II）吡唑基-苯并咪唑配合物

1-丁基-2-（（5-甲基-1 H-吡唑-3-基）甲基）-1 H-苯并咪唑（L）的三种单核配位化合物[CoL] Cl ₂（C1），[Co ₂合成了L ₂ ] Cl ₂ ·H ₂ O（C2）和[Zn ₂ L ₂ ] Cl ₂（C3）。他们的单晶X射线衍射分析显示C1和C2显示伪多态性。C1晶体结构中存在N–H⋯Cl和C–H⋯Cl氢键C3和C3分别帮助形成2D氢键合片和正交堆积[2D片+一对1D链]，从而导致超分子结构。N–H⋯Cl，C–H⋯Cl，O–H⋯Cl和C–H⋯O相互作用的结合产生了二维波纹氢键合板材，其中水分子包含在C2中。Hirshfeld表面分析证实氢键和π堆积接触稳定了晶体结构。这些金属配合物对大肠杆菌，铜绿假单胞菌和金黄色葡萄球菌具有良好的抗菌活性。尤其是归一化的最小抑菌浓度低至6.25μgmL ^-1记录菌株的C2。详细讨论了其结构与生物活性的关系。