{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,4,5]],"date-time":"2026-04-05T07:55:29Z","timestamp":1775375729776,"version":"3.50.1"},"reference-count":33,"publisher":"MDPI AG","issue":"11","license":[{"start":{"date-parts":[[2021,11,13]],"date-time":"2021-11-13T00:00:00Z","timestamp":1636761600000},"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 Tecnologia","doi-asserted-by":"publisher","award":["POCI-01-0145-FEDER-016793"],"award-info":[{"award-number":["POCI-01-0145-FEDER-016793"]}],"id":[{"id":"10.13039\/501100001871","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100001871","name":"Funda\u00e7\u00e3o para a Ci\u00eancia e Tecnologia","doi-asserted-by":"publisher","award":["UIDB\/04423\/2020 and UIDP\/04423\/2020"],"award-info":[{"award-number":["UIDB\/04423\/2020 and UIDP\/04423\/2020"]}],"id":[{"id":"10.13039\/501100001871","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100000780","name":"European Commission","doi-asserted-by":"publisher","award":["NORTE-01-0145-FEDER-000040"],"award-info":[{"award-number":["NORTE-01-0145-FEDER-000040"]}],"id":[{"id":"10.13039\/501100000780","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Marine Drugs"],"abstract":"<jats:p>Biofouling, which occurs when certain marine species attach and accumulate in artificial submerged structures, represents a serious economic and environmental issue worldwide. The discovery of new non-toxic and eco-friendly antifouling systems to control or prevent biofouling is, therefore, a practical and urgent need. In this work, the antifouling activity of a series of 24 xanthones, with chemical similarities to natural products, was exploited. Nine (1, 2, 4, 6, 8, 16, 19, 21, and 23) of the tested xanthones presented highly significant anti-settlement responses at 50 \u03bcM against the settlement of mussel Mytilus galloprovincialis larvae and low toxicity to this macrofouling species. Xanthones 21 and 23 emerged as the most effective larval settlement inhibitors (EC50 = 7.28 and 3.57 \u00b5M, respectively). Additionally, xanthone 23 exhibited a therapeutic ratio (LC50\/EC50) &gt; 15, as required by the US Navy program attesting its suitability as natural antifouling agents. From the nine tested xanthones, none of the compounds were found to significantly inhibit the growth of the marine biofilm-forming bacterial strains tested. Xanthones 4, 6, 8, 16, 19, 21, and 23 were found to be non-toxic to the marine non-target species Artemia salina (&lt;10% mortality at 50 \u03bcM). Insights on the antifouling mode of action of the hit xanthones 21 and 23 suggest that these two compounds affected similar molecular targets and cellular processes in mussel larvae, including that related to mussel adhesion capacity. This work exposes for the first time the relevance of C-1 aminated xanthones with a 3,4-dioxygenated pattern of substitution as new non-toxic products to prevent marine biofouling.<\/jats:p>","DOI":"10.3390\/md19110638","type":"journal-article","created":{"date-parts":[[2021,11,14]],"date-time":"2021-11-14T20:51:53Z","timestamp":1636923113000},"page":"638","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":14,"title":["From Natural Xanthones to Synthetic C-1 Aminated 3,4-Dioxygenated Xanthones as Optimized Antifouling Agents"],"prefix":"10.3390","volume":"19","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-4077-6060","authenticated-orcid":false,"given":"Diana I. S. P.","family":"Resende","sequence":"first","affiliation":[{"name":"CIIMAR\u2014Interdisciplinary Centre of Marine and Environmental Research, University of Porto, Terminal de Cruzeiros do Porto de Leix\u00f5es, Avenida General, Norton de Matos S\/N, 4450-208 Matosinhos, Portugal"},{"name":"Laboratory of Organic and Pharmaceutical Chemistry, Department of Chemical Sciences, Faculty of Pharmacy, University of Porto, Rua Jorge Viterbo Ferreira, 228, 4050-313 Porto, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-9356-7265","authenticated-orcid":false,"given":"Joana R.","family":"Almeida","sequence":"additional","affiliation":[{"name":"CIIMAR\u2014Interdisciplinary Centre of Marine and Environmental Research, University of Porto, Terminal de Cruzeiros do Porto de Leix\u00f5es, Avenida General, Norton de Matos S\/N, 4450-208 Matosinhos, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-7646-4026","authenticated-orcid":false,"given":"Sandra","family":"Pereira","sequence":"additional","affiliation":[{"name":"CIIMAR\u2014Interdisciplinary Centre of Marine and Environmental Research, University of Porto, Terminal de Cruzeiros do Porto de Leix\u00f5es, Avenida General, Norton de Matos S\/N, 4450-208 Matosinhos, Portugal"},{"name":"Department of Biology, Faculty of Sciences, University of Porto, Rua do Campo Alegre, 4069-007 Porto, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-4621-885X","authenticated-orcid":false,"given":"Alexandre","family":"Campos","sequence":"additional","affiliation":[{"name":"CIIMAR\u2014Interdisciplinary Centre of Marine and Environmental Research, University of Porto, Terminal de Cruzeiros do Porto de Leix\u00f5es, Avenida General, Norton de Matos S\/N, 4450-208 Matosinhos, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-6956-1736","authenticated-orcid":false,"given":"Agostinho","family":"Lemos","sequence":"additional","affiliation":[{"name":"Laboratory of Organic and Pharmaceutical Chemistry, Department of Chemical Sciences, Faculty of Pharmacy, University of Porto, Rua Jorge Viterbo Ferreira, 228, 4050-313 Porto, Portugal"}]},{"given":"Jeffrey E.","family":"Plowman","sequence":"additional","affiliation":[{"name":"AgResearch Ltd., 1365 Springs Rd, Lincoln 7674, New Zealand"}]},{"given":"Ancy","family":"Thomas","sequence":"additional","affiliation":[{"name":"AgResearch Ltd., 1365 Springs Rd, Lincoln 7674, New Zealand"}]},{"given":"Stefan","family":"Clerens","sequence":"additional","affiliation":[{"name":"AgResearch Ltd., 1365 Springs Rd, Lincoln 7674, New Zealand"},{"name":"Biomolecular Interaction Centre, University of Canterbury, Christchurch 8041, New Zealand"},{"name":"Riddet Institute, Massey University, Palmerston North 4474, New Zealand"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-3585-2417","authenticated-orcid":false,"given":"Vitor","family":"Vasconcelos","sequence":"additional","affiliation":[{"name":"CIIMAR\u2014Interdisciplinary Centre of Marine and Environmental Research, University of Porto, Terminal de Cruzeiros do Porto de Leix\u00f5es, Avenida General, Norton de Matos S\/N, 4450-208 Matosinhos, Portugal"},{"name":"Department of Biology, Faculty of Sciences, University of Porto, Rua do Campo Alegre, 4069-007 Porto, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-4676-1409","authenticated-orcid":false,"given":"Madalena","family":"Pinto","sequence":"additional","affiliation":[{"name":"CIIMAR\u2014Interdisciplinary Centre of Marine and Environmental Research, University of Porto, Terminal de Cruzeiros do Porto de Leix\u00f5es, Avenida General, Norton de Matos S\/N, 4450-208 Matosinhos, Portugal"},{"name":"Laboratory of Organic and Pharmaceutical Chemistry, Department of Chemical Sciences, Faculty of Pharmacy, University of Porto, Rua Jorge Viterbo Ferreira, 228, 4050-313 Porto, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-4150-8532","authenticated-orcid":false,"given":"Marta","family":"Correia-da-Silva","sequence":"additional","affiliation":[{"name":"CIIMAR\u2014Interdisciplinary Centre of Marine and Environmental Research, University of Porto, Terminal de Cruzeiros do Porto de Leix\u00f5es, Avenida General, Norton de Matos S\/N, 4450-208 Matosinhos, Portugal"},{"name":"Laboratory of Organic and Pharmaceutical Chemistry, Department of Chemical Sciences, Faculty of Pharmacy, University of Porto, Rua Jorge Viterbo Ferreira, 228, 4050-313 Porto, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-5397-4672","authenticated-orcid":false,"given":"Em\u00edlia","family":"Sousa","sequence":"additional","affiliation":[{"name":"CIIMAR\u2014Interdisciplinary Centre of Marine and Environmental Research, University of Porto, Terminal de Cruzeiros do Porto de Leix\u00f5es, Avenida General, Norton de Matos S\/N, 4450-208 Matosinhos, Portugal"},{"name":"Laboratory of Organic and Pharmaceutical Chemistry, Department of Chemical Sciences, Faculty of Pharmacy, University of Porto, Rua Jorge Viterbo Ferreira, 228, 4050-313 Porto, Portugal"}]}],"member":"1968","published-online":{"date-parts":[[2021,11,13]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","unstructured":"Vinagre, P.A., Simas, T., Cruz, E., Pinori, E., and Svenson, J. 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