{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,6,15]],"date-time":"2026-06-15T11:53:57Z","timestamp":1781524437543,"version":"3.54.1"},"reference-count":38,"publisher":"MDPI AG","issue":"2","license":[{"start":{"date-parts":[[2026,1,19]],"date-time":"2026-01-19T00:00:00Z","timestamp":1768780800000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100004004","name":"University of Trento","doi-asserted-by":"crossref","id":[{"id":"10.13039\/501100004004","id-type":"DOI","asserted-by":"crossref"}]},{"name":"lovenian Research and Innovation Agency","award":["P1-0207"],"award-info":[{"award-number":["P1-0207"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Molecules"],"abstract":"<jats:p>In the search for solutions to the global health threat posed by antimicrobial resistance, the development of new compounds is crucial. In this context, the in vitro testing of known indolizinoquinolinedione analogs 1\u20137 revealed that N,N-syn regioisomers are more active than N,N-anti regioisomers. In particular, compound 2 (ethyl 5,12-dihydro-5,12-dioxoindolizino[2,3-g]quinoline-6-carboxylate) exhibited the most significant activity against Bacillus subtilis, B. cereus, Staphylococcus aureus, and methicillin-resistant S. aureus (MRSA) bacteria. The reported increased bioactivity of metal complexes and their ability to overcome drug resistance through metal coordination have induced the study of new metal complexes of compound 2. FT-IR spectroscopy combined with DFT-simulated spectra confirmed the C=O chelation in all Zn, Cu, and Mn complexes 8\u201310. ESI-MS isotopic cluster analysis and UV-Vis-derived Job\u2019s plot provided significant evidence for 1:1 chelation. Finally, 1H NMR data were correlated to the DFT-calculated charge distribution. Complexes 8\u201310 displayed similar activity against B. subtilis, although this was lower than that for 2, and there were comparable effects with 2 and vancomycin antibiotic against S. aureus. FTsZ protein as a potential target of B. subtilis and DNA gyrase of S. aureus and MRSA were studied by docking calculations, revealing a good correlation with the in vitro results.<\/jats:p>","DOI":"10.3390\/molecules31020348","type":"journal-article","created":{"date-parts":[[2026,1,20]],"date-time":"2026-01-20T08:36:33Z","timestamp":1768898193000},"page":"348","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":1,"title":["Indolizinoquinolinedione Metal Complexes: Structural Characterization, In Vitro Antibacterial, and In Silico Studies"],"prefix":"10.3390","volume":"31","author":[{"ORCID":"https:\/\/orcid.org\/0000-0003-4359-6951","authenticated-orcid":false,"given":"Jacopo","family":"Vigna","sequence":"first","affiliation":[{"name":"Laboratory of Bioorganic Chemistry, Department of Physics, University of Trento, 38123 Trento, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Michael","family":"Marchesi","sequence":"additional","affiliation":[{"name":"Laboratory of Bioorganic Chemistry, Department of Physics, University of Trento, 38123 Trento, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Ibtissem","family":"Djinni","sequence":"additional","affiliation":[{"name":"Laboratory of Applied Microbiology, Faculty of Natural and Life Sciences, University of Bejaia, Targa Ouzemmour, B\u00e9ja\u00efa 06000, Algeria"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Mi\u0161a Mojca","family":"Cajnko","sequence":"additional","affiliation":[{"name":"Department of Biology, Biotechnical Faculty, University of Ljubljana, Jamnikarjeva 101, 1000 Ljubljana, Slovenia"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-4023-5379","authenticated-orcid":false,"given":"Kristina","family":"Sep\u010di\u0107","sequence":"additional","affiliation":[{"name":"Department of Biology, Biotechnical Faculty, University of Ljubljana, Jamnikarjeva 101, 1000 Ljubljana, Slovenia"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0009-0000-2460-3015","authenticated-orcid":false,"given":"Andrea","family":"Defant","sequence":"additional","affiliation":[{"name":"Laboratory of Bioorganic Chemistry, Department of Physics, University of Trento, 38123 Trento, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-0297-3685","authenticated-orcid":false,"given":"Ines","family":"Mancini","sequence":"additional","affiliation":[{"name":"Laboratory of Bioorganic Chemistry, Department of Physics, University of Trento, 38123 Trento, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2026,1,19]]},"reference":[{"key":"ref_1","unstructured":"(2025, June 24). 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