Heptanuclear zinc(II) complex with metronidazole : synthesis, structure and antibacterial activity

Modec, Barbara (author), Podjed Rihtaršič, Nina (author), Hrast Rambaher, Martina (author), Golob, Majda (author)

The reaction systems consisting of mononuclear zinc(II) acetate dihydrate, metronidazole (met) and nitrile solvent (acetonitrile or propionitrile) have afforded heptanuclear zinc(II) compounds, [Zn$_7$O$_2$(CH$_3$COO)$_{10}$(met)$_2$]∙2CH$_3$CN (1) and [Zn$_7$O$_2$(CH$_3$COO)$_{10}$(met)$_2$]∙2CH$_3$CH$_2$CN (2). Heptanuclear compounds 1 and 2 formed regardless of the reaction conditions: either under ambient conditions or when heated at 105 °C for 24 h in autoclaves. Their compositions were authenticated using single crystal X-ray crystallography. Both compounds feature the previously known {Zn$_7$O$_2$(CH$_3$COO)$_{10}$} structural core whose metal ions are interconnected via acetate and μ$_4$-oxide ligands. Two metronidazole ligands are coordinated to this core via imidazole nitrogen atoms. The zinc ions of the heptanuclear complex adopt different coordination environments: four are in nearly tetrahedral environments of four oxygen atoms, two are surrounded by NO$_4$ donor atoms which define vertices of a distorted square pyramid and one is in an octahedral environment of six oxygen atoms. The Znsingle bondO bonding patterns reflect both the nature and the number of donors. The solid-state structures of 1 and 2 display different intermolecular connectivities. Antibacterial testing against a series of Gram-positive and Gram-negative bacteria shows that [Zn$_7$O$_2$(CH$_3$COO)$_{10}$(met)$_2$]∙2CH$_3$CN (1) exhibits moderate activity against Staphylococcus epidermidis. Overall, the study advances the field of metal-based antimicrobial agents and offers new perspectives on addressing antibiotic resistance.

• Language: English
• Keywords: Zinc(II), Zn$_4$(μ$_4$-O) entity, heptanuclear core, metronidazole, crystal structure, antibacterial activity
• Work type: Article
• Typology: 1.01 - Original Scientific Article
• Organization: FKKT - Faculty of Chemistry and Chemical Technology; FFA - Faculty of Pharmacy; VF - Veterinary Faculty
• Publication status: Published
• Publication version: Version of Record
• Year: 2026
• Number of pages: 8 str.
• Numbering: Vol. 20, art. 102267
• PID: 20.500.12556/RUL-181550
• UDC: 546.47:615.28
• ISSN on article: 2211-7156
• DOI: 10.1016/j.rechem.2025.102962
• COBISS.SI-ID: 262343683
• Publication date in RUL: 10.04.2026

Record is a part of a journal

• Title: Results in chemistry
• Publisher: Elsevier B.V.
• ISSN: 2211-7156
• COBISS.SI-ID: 56332803

Licences

• License: CC BY 4.0, Creative Commons Attribution 4.0 International
• Link: http://creativecommons.org/licenses/by/4.0/
• Description: This is the standard Creative Commons license that gives others maximum freedom to do what they want with the work as long as they credit the author.

Secondary language

• Language: Slovenian
• Keywords: cink(II), Zn$_4$(μ$_4$-O) entiteta, heptanuklearno jedro, metronidazol, kristalna struktura, antibakterijsko delovanje