{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2025,10,14]],"date-time":"2025-10-14T14:44:06Z","timestamp":1760453046173,"version":"build-2065373602"},"reference-count":29,"publisher":"MDPI AG","issue":"12","license":[{"start":{"date-parts":[[2020,6,24]],"date-time":"2020-06-24T00:00:00Z","timestamp":1592956800000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100001871","name":"Funda\u00e7\u00e3o para a Ci\u00eancia e a Tecnologia","doi-asserted-by":"publisher","award":["PTDC\/QUI-OUT\/27996\/2017"],"award-info":[{"award-number":["PTDC\/QUI-OUT\/27996\/2017"]}],"id":[{"id":"10.13039\/501100001871","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100008530","name":"European Regional Development Fund","doi-asserted-by":"publisher","award":["LISBOA-01-0145-FEDER-007660","UIDB\/00313\/2020"],"award-info":[{"award-number":["LISBOA-01-0145-FEDER-007660","UIDB\/00313\/2020"]}],"id":[{"id":"10.13039\/501100008530","id-type":"DOI","asserted-by":"publisher"}]},{"name":"GREEN-it, Bioresources for Sustainability","award":["UID\/Multi\/04551\/2013"],"award-info":[{"award-number":["UID\/Multi\/04551\/2013"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Molecules"],"abstract":"<jats:p>The synthesis and structural modulation of five pro-ligand salts was achieved using alternative sustainable synthetic strategies, the use of microwaves being the method of choice, with an 81% yield and an E factor of 43 for 3d. After complexation with Fe3(CO)12 by direct reaction with the appropriate pro-ligands at 130 \u00b0C, a set of iron(II) N-heterocyclic carbene (NHC) complexes were isolated and fully characterized (via 1H and 13C NMR and IR spectroscopy and elemental analysis). The antibacterial activities of the iron(II)-NHC complexes were tested against standard World Health Organization priority bacterial strains: Staphylococcus aureus ATCC 29213 and Escherichia coli ATCC 25922. The results showed a significant effect of the Fe(II)-NHC side-chain on the antibacterial activity against both Gram-negative and Gram-positive bacteria. Among all compounds, the most lipophilic iron complex, 3b, was found to be the most active one, with a minimum inhibitory concentration of 8 \u00b5g\/mL. Pioneering mechanistic studies suggested an alternative mechanism of action (OH\u00b7 formation), which opens the way for the development of a new class of antibiotics.<\/jats:p>","DOI":"10.3390\/molecules25122917","type":"journal-article","created":{"date-parts":[[2020,6,24]],"date-time":"2020-06-24T10:54:59Z","timestamp":1592996099000},"page":"2917","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":6,"title":["Synthesis of Iron(II)\u2013N-Heterocyclic Carbene Complexes: Paving the Way for a New Class of Antibiotics"],"prefix":"10.3390","volume":"25","author":[{"ORCID":"https:\/\/orcid.org\/0000-0001-8229-0651","authenticated-orcid":false,"given":"Carolina S.","family":"Vinagreiro","sequence":"first","affiliation":[{"name":"Coimbra Chemistry Centre, University of Coimbra, Rua Larga, 3004-535 Coimbra, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-0120-9140","authenticated-orcid":false,"given":"Rita","family":"Lopes","sequence":"additional","affiliation":[{"name":"ITQB NOVA, Instituto de Tecnologia Qu\u00edmica e Biol\u00f3gica Ant\u00f3nio Xavier, Av. da Rep\u00fablica, 2780-157 Oeiras, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-4958-7677","authenticated-orcid":false,"given":"Beatriz","family":"Royo","sequence":"additional","affiliation":[{"name":"ITQB NOVA, Instituto de Tecnologia Qu\u00edmica e Biol\u00f3gica Ant\u00f3nio Xavier, Av. da Rep\u00fablica, 2780-157 Oeiras, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-7479-8540","authenticated-orcid":false,"given":"Gabriela Jorge","family":"Da Silva","sequence":"additional","affiliation":[{"name":"Faculty of Pharmacy and Center for Neurosciences and Cell Biology, University of Coimbra, Polo das Ci\u00eancias da Sa\u00fade, Azinhaga de Santa Comba, 3000-548 Coimbra, Portugal"}]},{"given":"Mariette M.","family":"Pereira","sequence":"additional","affiliation":[{"name":"Coimbra Chemistry Centre, University of Coimbra, Rua Larga, 3004-535 Coimbra, Portugal"}]}],"member":"1968","published-online":{"date-parts":[[2020,6,24]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"336","DOI":"10.1038\/nature17042","article-title":"Antibacterial drug discovery in the resistance era","volume":"529","author":"Brown","year":"2016","journal-title":"Nature"},{"key":"ref_2","unstructured":"World Health Organization (2017). 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