{
  "abstract": "Antibacterial resistance continues to drive the need for exploring novel chemical spaces beyond conventional organic scaffolds. Metal-based compounds have emerged as a promising class of antibiotic candidates, demonstrating high hit rates against priority bacterial pathogens without exhibiting increased toxicity compared to purely organic molecules. Here, we report a one-pot, three-component combinatorial strategy for the synthesis of piano-stool Ir-(III) cyclopentadienyl Schiff-base complexes as potential antibacterial agents. Using 15 picolinaldehydes (A-O), 24 amines (1-24), and four Cp/Cp* iridium precursors (Cp1-4), a library of 1440 complexes was generated and screened directly from crude reaction mixtures in a direct-to-biology approach. Biological screening revealed pronounced activity against Gram-positive Staphylococcus aureus, particularly for biphenyl-substituted Cp (Cp2) complexes, while no activity was observed against Gram-negative bacteria. A subset of the compounds exhibited potent and selective antibacterial activity with low mammalian cell toxicity. Dose-response validation identified 4 promising hit candidates, of which Ir15 displayed low-micromolar activity against a panel of Gram-positive pathogens, limited hemolysis, and moderate cytotoxicity. Initial mechanistic studies indicate that Ir15 acts through a membrane-associated mode of action involving mild membrane depolarization without large pore formation, alongside changes in nucleoid morphology. Overall, this work establishes Ir-(III)-Cp Schiff-base complexes as a modular antibacterial platform and identifies Ir15 as a promising lead compound for further optimization.",
  "abstract_shown": true,
  "affiliations": [
    "Department of Chemistry, Biochemistry & Pharmaceutical Sciences, University of Bern, Freiestrasse 3, 3012 Bern, Switzerland.",
    "Department of Chemistry, University of York, York YO10 5DD, U.K.",
    "Department of Chemistry \"Ugo Schiff\", University of Florence, Sesto Fiorentino 50019, Italy."
  ],
  "article_type": "research article",
  "arxiv": null,
  "author_total": 7,
  "authors": [
    {
      "affs": [
        0,
        1
      ],
      "name": "Çağrı Özsan"
    },
    {
      "affs": [
        0,
        1
      ],
      "name": "Athi Welsh"
    },
    {
      "affs": [
        2
      ],
      "name": "Stefano Zineddu"
    },
    {
      "affs": [
        1
      ],
      "name": "David R Husbands",
      "orcid": "0000-0001-8693-7766"
    },
    {
      "affs": [
        1
      ],
      "name": "Kiera Robinson"
    },
    {
      "affs": [
        1
      ],
      "name": "Anson Kwok-Hei Chau"
    },
    {
      "affs": [
        0,
        1
      ],
      "name": "Angelo Frei",
      "orcid": "0000-0001-6169-2491"
    }
  ],
  "bibtex": "https://research.draconitic.com/paper/f8zjd5ymf6tbh.bib",
  "cited_by": 1,
  "doi": "10.1021/jacsau.6c00813",
  "fulltext_url": "https://europepmc.org/articles/PMC13714831",
  "id": "f8zjd5ymf6tbh",
  "issns": [
    "2691-3704"
  ],
  "landing_url": "https://europepmc.org/article/MED/42953627",
  "language": "eng",
  "licence": "CC-BY-NC-ND",
  "licence_label": "CC BY-NC-ND",
  "licence_source": "article",
  "licence_url": "https://creativecommons.org/licenses/by-nc-nd/4.0/",
  "metadata_licence": null,
  "native_subjects": [
    [
      "heading",
      "Article"
    ],
    [
      "openalex",
      "2730|Metal complexes synthesis and properties"
    ]
  ],
  "openalex": "W7213610390",
  "pdf_url": "https://europepmc.org/articles/PMC13714831?pdf=render",
  "pmcid": "PMC13714831",
  "pmid": "42953627",
  "published": "2026-09-18",
  "publisher": "American Chemical Society",
  "ris": "https://research.draconitic.com/paper/f8zjd5ymf6tbh.ris",
  "sources": [
    {
      "first_seen": "2026-10-31T00:20:41Z",
      "native_id": "MED:42953627",
      "source": "europepmc",
      "url": "https://europepmc.org/article/MED/42953627"
    },
    {
      "first_seen": "2026-11-01T12:22:15Z",
      "native_id": "PMC13714831",
      "source": "pmc",
      "url": "https://doi.org/10.1021/jacsau.6c00813"
    }
  ],
  "subjects": [
    {
      "field": "medicine",
      "origin": "openalex:2730|Metal complexes synthesis and properties",
      "subfield": "oncology"
    }
  ],
  "title": "Unlocking Iridium Chemical Space for Antibiotic Discovery through One-Pot Combinatorial Synthesis in a Direct-to-Biology Approach.",
  "title_text": "Unlocking Iridium Chemical Space for Antibiotic Discovery through One-Pot Combinatorial Synthesis in a Direct-to-Biology Approach.",
  "type": "peer-reviewed",
  "updated_at": "2026-11-01T12:22:15Z",
  "url": "https://research.draconitic.com/paper/f8zjd5ymf6tbh",
  "venue": "JACS Au",
  "versions": []
}