{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,1,10]],"date-time":"2026-01-10T00:32:42Z","timestamp":1768005162904,"version":"3.49.0"},"reference-count":22,"publisher":"MDPI AG","issue":"8","license":[{"start":{"date-parts":[[2023,8,7]],"date-time":"2023-08-07T00:00:00Z","timestamp":1691366400000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"Catalyst: Seeding Dumont d\u2019Urville NZ-France Science &amp; Technology Support Programme","award":["19-UOA-057-DDU"],"award-info":[{"award-number":["19-UOA-057-DDU"]}]},{"name":"New Zealand Ministry of Business, Innovation and Employment and administered by the Royal Society Te Ap\u0101rangi","award":["19-UOA-057-DDU"],"award-info":[{"award-number":["19-UOA-057-DDU"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Biomolecules"],"abstract":"<jats:p>The widespread incidence of antimicrobial resistance necessitates the discovery of new classes of antimicrobials as well as adjuvant molecules that can restore the action of ineffective antibiotics. Herein, we report the synthesis of a new class of indole-3-acetamido-polyamine conjugates that were evaluated for antimicrobial activities against a panel of bacteria and two fungi, and for the ability to enhance the action of doxycycline against Pseudomonas aeruginosa and erythromycin against Escherichia coli. Compounds 14b, 15b, 17c, 18a, 18b, 18d, 19b, 19e, 20c and 20d exhibited strong growth inhibition of methicillin-resistant Staphylococcus aureus (MRSA) and Cryptococcus neoformans, with minimum inhibitory concentrations (MIC) typically less than 0.2 \u00b5M. Four analogues, including a 5-bromo 15c and three 5-methoxyls 16d\u2013f, also exhibited intrinsic activity towards E. coli. Antibiotic kill curve analysis of 15c identified it to be a bactericide. While only one derivative was found to (weakly) enhance the action of erythromycin against E. coli, three examples, including 15c, were found to be strong enhancers of the antibiotic action of doxycycline against P. aeruginosa. Collectively, these results highlight the promising potential of \u03b1,\u03c9-disubstituted indole-3-acetamido polyamine conjugates as antimicrobials and antibiotic adjuvants.<\/jats:p>","DOI":"10.3390\/biom13081226","type":"journal-article","created":{"date-parts":[[2023,8,7]],"date-time":"2023-08-07T06:37:31Z","timestamp":1691390251000},"page":"1226","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":7,"title":["Indole-3-Acetamido-Polyamines as Antimicrobial Agents and Antibiotic Adjuvants"],"prefix":"10.3390","volume":"13","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-1477-4117","authenticated-orcid":false,"given":"Kenneth","family":"Sue","sequence":"first","affiliation":[{"name":"School of Chemical Sciences, The University of Auckland, Private Bag 92019, Auckland 1142, New Zealand"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-3883-0109","authenticated-orcid":false,"given":"Melissa M.","family":"Cadelis","sequence":"additional","affiliation":[{"name":"School of Chemical Sciences, The University of Auckland, Private Bag 92019, Auckland 1142, New Zealand"},{"name":"School of Medical Sciences, The University of Auckland, Private Bag 92019, Auckland 1142, New Zealand"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Evangelene S.","family":"Gill","sequence":"additional","affiliation":[{"name":"School of Chemical Sciences, The University of Auckland, Private Bag 92019, Auckland 1142, New Zealand"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Florent","family":"Rouvier","sequence":"additional","affiliation":[{"name":"Membranes et Cibles Th\u00e9rapeutiques (MCT), L\u2019Institut National de la Sant\u00e9 et de la Recherche M\u00e9dicale (INSERM), Aix-Marseille Universite, 27 bd Jean Moulin, 13385 Marseille, France"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Marie-Lise","family":"Bourguet-Kondracki","sequence":"additional","affiliation":[{"name":"Laboratoire Mol\u00e9cules de Communication et Adaptation des Micro-Organismes, UMR 7245 CNRS, Mus\u00e9um National d\u2019Histoire Naturelle, 57 Rue Cuvier (C.P. 54), 75005 Paris, France"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-9355-8980","authenticated-orcid":false,"given":"Jean Michel","family":"Brunel","sequence":"additional","affiliation":[{"name":"Membranes et Cibles Th\u00e9rapeutiques (MCT), L\u2019Institut National de la Sant\u00e9 et de la Recherche M\u00e9dicale (INSERM), Aix-Marseille Universite, 27 bd Jean Moulin, 13385 Marseille, France"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-5492-5269","authenticated-orcid":false,"given":"Brent R.","family":"Copp","sequence":"additional","affiliation":[{"name":"School of Chemical Sciences, The University of Auckland, Private Bag 92019, Auckland 1142, New Zealand"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2023,8,7]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"29","DOI":"10.1038\/nrd2201","article-title":"Drugs for Bad Bugs: Confronting the Challenges of Antibacterial Discovery","volume":"6","author":"Payne","year":"2007","journal-title":"Nat. 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