{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,8,28]],"date-time":"2026-08-28T20:11:58Z","timestamp":1787947918897,"version":"build-2784847793"},"reference-count":49,"publisher":"MDPI AG","issue":"3","license":[{"start":{"date-parts":[[2025,3,16]],"date-time":"2025-03-16T00:00:00Z","timestamp":1742083200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Antibiotics"],"abstract":"<jats:p>Background\/Objectives: The discovery of new molecules to which bacteria have not yet developed resistance is a significant medical priority. Synthetic flavonoids are good candidates for developing new antimicrobials. Our study investigates a series of newly synthesized tricyclic flavonoids with several different substituents on the flavonoid core. Methods: By varying the nature of the substituents on rings A and B, a structure\u2013activity relationship study using different microbial strains has been performed. The antibacterial and antifungal properties of these compounds have been investigated against Gram-positive and Gram-negative bacteria and several Candida strains. Results: All seven tested compounds have been found to exhibit the highest antimicrobial activity against S. aureus, with an inhibition zone of up to 23 mm. The tricyclic flavonoids 5c, 5e, and 5f showed good antifungal properties against C. parapsilosis, with an inhibition zone of around 17 mm. Conclusions: All the data support the idea that flavonoids 5 are reliable candidates for developing effective antimicrobial agents.<\/jats:p>","DOI":"10.3390\/antibiotics14030307","type":"journal-article","created":{"date-parts":[[2025,3,17]],"date-time":"2025-03-17T07:49:57Z","timestamp":1742197797000},"page":"307","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":4,"title":["Antibacterial and Antifungal Properties of New Synthetic Tricyclic Flavonoids"],"prefix":"10.3390","volume":"14","author":[{"ORCID":"https:\/\/orcid.org\/0000-0003-1789-2108","authenticated-orcid":false,"given":"Laura Gabriela","family":"Sarbu","sequence":"first","affiliation":[{"name":"Department of Chemistry, Alexandru Ioan Cuza University of Iasi, No. 11 Carol I Blvd., 700506 Iasi, Romania"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-3080-1709","authenticated-orcid":false,"given":"Irina","family":"Rosca","sequence":"additional","affiliation":[{"name":"Intelcenter, Petru Poni Institute of Macromolecular Chemistry, No. 41A Grigore Ghica Voda Alley, 700487 Iasi, Romania"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-4483-873X","authenticated-orcid":false,"given":"Mihail Lucian","family":"Birsa","sequence":"additional","affiliation":[{"name":"Department of Chemistry, Alexandru Ioan Cuza University of Iasi, No. 11 Carol I Blvd., 700506 Iasi, Romania"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2025,3,16]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"629","DOI":"10.1016\/S0140-6736(21)02724-0","article-title":"Global burden of bacterial antimicrobial resistance in 2019: A systematic analysis","volume":"399","author":"Murray","year":"2022","journal-title":"Lancet"},{"key":"ref_2","doi-asserted-by":"crossref","unstructured":"Tang, K.W.K., Millar, B.C., and Moore, J.E. 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