{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,5,9]],"date-time":"2026-05-09T11:16:26Z","timestamp":1778325386777,"version":"3.51.4"},"reference-count":32,"publisher":"MDPI AG","issue":"10","license":[{"start":{"date-parts":[[2018,10,12]],"date-time":"2018-10-12T00:00:00Z","timestamp":1539302400000},"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":["POCI-01-0145-FEDER-028736, POCI-01-0145-FEDER-016790 (PTDC\/MAR-BIO\/4694\/2014; 3599-PPCDT)"],"award-info":[{"award-number":["POCI-01-0145-FEDER-028736, POCI-01-0145-FEDER-016790 (PTDC\/MAR-BIO\/4694\/2014; 3599-PPCDT)"]}],"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":["UID\/Multi\/04423\/2013, NORTE-01-0145-FEDER-000035, NOVELMAR\/BPD_2\/2016-019, NOVELMAR\/BPD\/2017\/012"],"award-info":[{"award-number":["UID\/Multi\/04423\/2013, NORTE-01-0145-FEDER-000035, NOVELMAR\/BPD_2\/2016-019, NOVELMAR\/BPD\/2017\/012"]}],"id":[{"id":"10.13039\/501100008530","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Molecules"],"abstract":"<jats:p>Due to the emergence of multidrug-resistant pathogenic microorganisms, the search for new antimicrobial compounds plays an important role in current medicinal chemistry research. Inspired by lichen antimicrobial xanthones, a series of novel chlorinated xanthones was prepared using five chlorination methods (Methods A\u2013E) to obtain different patterns of substitution in the xanthone scaffold. All the synthesized compounds were evaluated for their antimicrobial activity. Among them, 3-chloro-4,6-dimethoxy-1-methyl-9H-xanthen-9-one 15 showed promising antibacterial activity against E. faecalis (ATCC 29212 and 29213) and S. aureus ATCC 29213. 2,7-Dichloro-3,4,6-trimethoxy-1-methyl-9H-xanthen-9-one 18 revealed a potent fungistatic and fungicidal activity against dermatophytes clinical strains (T. rubrum, M. canis, and E. floccosum (MIC = 4\u20138 \u00b5g\/mL)). Moreover, when evaluated for its synergistic effect for T. rubrum, compound 18 exhibited synergy with fluconazole (\u03a3FIC = 0.289). These results disclosed new hit xanthones for both antibacterial and antifungal activity.<\/jats:p>","DOI":"10.3390\/molecules23102617","type":"journal-article","created":{"date-parts":[[2018,10,12]],"date-time":"2018-10-12T10:54:03Z","timestamp":1539341643000},"page":"2617","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":36,"title":["Lichen Xanthones as Models for New Antifungal Agents"],"prefix":"10.3390","volume":"23","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-4077-6060","authenticated-orcid":false,"given":"Diana I. S. P.","family":"Resende","sequence":"first","affiliation":[{"name":"Laboratory of Organic and Pharmaceutical Chemistry (LQOF), Department of Chemical Sciences, Faculty of Pharmacy, University of Porto, Rua de Jorge Viterbo Ferreira, 228, 4050-313 Porto, Portugal"},{"name":"Interdisciplinary Centre of Marine and Environmental Research (CIIMAR), Terminal de Cruzeiros do Porto de Leix\u00f5es, Av. General Norton de Matos s\/n, 4450-208 Matosinhos, Portugal"}]},{"given":"Patr\u00edcia","family":"Pereira-Terra","sequence":"additional","affiliation":[{"name":"Interdisciplinary Centre of Marine and Environmental Research (CIIMAR), Terminal de Cruzeiros do Porto de Leix\u00f5es, Av. General Norton de Matos s\/n, 4450-208 Matosinhos, Portugal"},{"name":"Laboratory of Microbiology, Department of Aquatic Production, Institute of Biomedical Sciences Abel Salazar (ICBAS), University of Porto, Rua de Jorge Viterbo Ferreira, 228, 4050-313 Porto, Portugal"}]},{"given":"\u00c2ngela S.","family":"In\u00e1cio","sequence":"additional","affiliation":[{"name":"Interdisciplinary Centre of Marine and Environmental Research (CIIMAR), Terminal de Cruzeiros do Porto de Leix\u00f5es, Av. General Norton de Matos s\/n, 4450-208 Matosinhos, Portugal"},{"name":"Laboratory of Microbiology, Department of Aquatic Production, Institute of Biomedical Sciences Abel Salazar (ICBAS), University of Porto, Rua de Jorge Viterbo Ferreira, 228, 4050-313 Porto, Portugal"}]},{"given":"Paulo Martins da","family":"Costa","sequence":"additional","affiliation":[{"name":"Interdisciplinary Centre of Marine and Environmental Research (CIIMAR), Terminal de Cruzeiros do Porto de Leix\u00f5es, Av. General Norton de Matos s\/n, 4450-208 Matosinhos, Portugal"},{"name":"Laboratory of Microbiology, Department of Aquatic Production, Institute of Biomedical Sciences Abel Salazar (ICBAS), University of Porto, Rua de Jorge Viterbo Ferreira, 228, 4050-313 Porto, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-2948-5809","authenticated-orcid":false,"given":"Eug\u00e9nia","family":"Pinto","sequence":"additional","affiliation":[{"name":"Interdisciplinary Centre of Marine and Environmental Research (CIIMAR), Terminal de Cruzeiros do Porto de Leix\u00f5es, Av. General Norton de Matos s\/n, 4450-208 Matosinhos, Portugal"},{"name":"Laboratory of Microbiology, Department of Biological Sciences, Faculty of Pharmacy, University of Porto, Rua de 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":"Laboratory of Organic and Pharmaceutical Chemistry (LQOF), Department of Chemical Sciences, Faculty of Pharmacy, University of Porto, Rua de Jorge Viterbo Ferreira, 228, 4050-313 Porto, Portugal"},{"name":"Interdisciplinary Centre of Marine and Environmental Research (CIIMAR), Terminal de Cruzeiros do Porto de Leix\u00f5es, Av. General Norton de Matos s\/n, 4450-208 Matosinhos, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-4676-1409","authenticated-orcid":false,"given":"Madalena M. M.","family":"Pinto","sequence":"additional","affiliation":[{"name":"Laboratory of Organic and Pharmaceutical Chemistry (LQOF), Department of Chemical Sciences, Faculty of Pharmacy, University of Porto, Rua de Jorge Viterbo Ferreira, 228, 4050-313 Porto, Portugal"},{"name":"Interdisciplinary Centre of Marine and Environmental Research (CIIMAR), Terminal de Cruzeiros do Porto de Leix\u00f5es, Av. General Norton de Matos s\/n, 4450-208 Matosinhos, Portugal"}]}],"member":"1968","published-online":{"date-parts":[[2018,10,12]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"470","DOI":"10.3389\/fmicb.2016.00470","article-title":"Antimicrobial drugs in fighting against antimicrobial resistance","volume":"7","author":"Cheng","year":"2016","journal-title":"Front. 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