{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,10,6]],"date-time":"2026-10-06T19:22:46Z","timestamp":1791314566046,"version":"4.3.1"},"reference-count":17,"publisher":"MDPI AG","issue":"9","license":[{"start":{"date-parts":[[2015,9,15]],"date-time":"2015-09-15T00:00:00Z","timestamp":1442275200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100000925","name":"NHMRC","doi-asserted-by":"publisher","award":["APP1024314"],"award-info":[{"award-number":["APP1024314"]}],"id":[{"id":"10.13039\/501100000925","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100001031","name":"ARC","doi-asserted-by":"publisher","award":["LP120200339"],"award-info":[{"award-number":["LP120200339"]}],"id":[{"id":"10.13039\/501100001031","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100001031","name":"ARC","doi-asserted-by":"publisher","award":["LE0668477"],"award-info":[{"award-number":["LE0668477"]}],"id":[{"id":"10.13039\/501100001031","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100001031","name":"ARC","doi-asserted-by":"publisher","award":["LE0237908"],"award-info":[{"award-number":["LE0237908"]}],"id":[{"id":"10.13039\/501100001031","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Marine Drugs"],"abstract":"<jats:p>Six regioisomers associated with the tricyclic core of thiaplakortones A\u2013D have been synthesized. Reaction of 1H-indole-4,7-dione and 1-tosyl-1H-indole-4,7-dione with  2-aminoethanesulfinic acid afforded a regioisomeric series, which was subsequently deprotected and oxidized to yield the tricyclic core scaffolds present in the thiaplakortones. All compounds were fully characterized using NMR and MS data. A single crystal X-ray structure was obtained on one of the N-tosyl derivatives. All compounds were screened for in vitro antiplasmodial activity against chloroquine-sensitive (3D7) and multidrug-resistant (Dd2) Plasmodium falciparum parasite lines. Several analogues displayed potent inhibition of P. falciparum growth (IC50 &lt; 500 nM) but only moderate selectivity for P. falciparum versus human neonatal foreskin fibroblast cells.<\/jats:p>","DOI":"10.3390\/md13095784","type":"journal-article","created":{"date-parts":[[2015,9,16]],"date-time":"2015-09-16T10:33:36Z","timestamp":1442399616000},"page":"5784-5795","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":9,"title":["Synthesis and Antiplasmodial Evaluation of Analogues Based on the Tricyclic Core of Thiaplakortones A\u2013D"],"prefix":"10.3390","volume":"13","author":[{"given":"Brett","family":"Schwartz","sequence":"first","affiliation":[{"name":"Eskitis Institute for Drug Discovery, Griffith University, Nathan, Qld 4111, Australia"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Mark","family":"Coster","sequence":"additional","affiliation":[{"name":"Eskitis Institute for Drug Discovery, Griffith University, Nathan, Qld 4111, Australia"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Tina","family":"Skinner-Adams","sequence":"additional","affiliation":[{"name":"Eskitis Institute for Drug Discovery, Griffith University, Nathan, Qld 4111, Australia"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Katherine","family":"Andrews","sequence":"additional","affiliation":[{"name":"Eskitis Institute for Drug Discovery, Griffith University, Nathan, Qld 4111, Australia"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Jonathan","family":"White","sequence":"additional","affiliation":[{"name":"School of Chemistry and Bio21 Institute, University of Melbourne, Parkville, Vic 3052, Australia"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-4291-7573","authenticated-orcid":false,"given":"Rohan","family":"Davis","sequence":"additional","affiliation":[{"name":"Eskitis Institute for Drug Discovery, Griffith University, Nathan, Qld 4111, Australia"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2015,9,15]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"9608","DOI":"10.1021\/jo400988y","article-title":"Thiaplakortones A-D: Antimalarial Thiazine Alkaloids from the Australian Marine Sponge Plakortis lita","volume":"78","author":"Davis","year":"2013","journal-title":"J. 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