{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,8,27]],"date-time":"2026-08-27T22:04:12Z","timestamp":1787868252946,"version":"build-2784847793"},"reference-count":26,"publisher":"MDPI AG","issue":"19","license":[{"start":{"date-parts":[[2021,9,22]],"date-time":"2021-09-22T00:00:00Z","timestamp":1632268800000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100000925","name":"National Health and Medical Research Council","doi-asserted-by":"publisher","award":["APP1016699"],"award-info":[{"award-number":["APP1016699"]}],"id":[{"id":"10.13039\/501100000925","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Molecules"],"abstract":"<jats:p>The dihydropyranoindole structures were previously identified as promising scaffolds for improving the anti-cancer activity of histone deacetylase inhibitors. This work describes the synthesis of related furoindoles and their ability to synergize with suberoylanilide hydroxamic acid (SAHA) against neuroblastoma and breast cancer cells. The nucleophilic substitution of hydroxyindole methyl esters with \u03b1-haloketones yielded the corresponding arylether ketones, which were subsequently cyclized to tricyclic and tetracyclic furoindoles. The furoindoles showed promising individual cytotoxic efficiency against breast cancer cells, as well as decent SAHA enhancement against cancer cells in select cases. Interestingly, the best IC50 value was obtained with the non-cyclized intermediate.<\/jats:p>","DOI":"10.3390\/molecules26195745","type":"journal-article","created":{"date-parts":[[2021,9,22]],"date-time":"2021-09-22T22:50:48Z","timestamp":1632351048000},"page":"5745","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":6,"title":["Synthesis and Characterisation of Novel Tricyclic and Tetracyclic Furoindoles: Biological Evaluation as SAHA Enhancer against Neuroblastoma and Breast Cancer Cells"],"prefix":"10.3390","volume":"26","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-3909-0694","authenticated-orcid":false,"given":"Murat","family":"Bingul","sequence":"first","affiliation":[{"name":"School of Chemistry, The University of New South Wales, Sydney, NSW 2052, Australia"},{"name":"Lowy Cancer Research Centre, Children\u2019s Cancer Institute, UNSW Sydney, Sydney, NSW 2031, Australia"},{"name":"School of Pharmacy, Dicle University, Diyarbak\u0131r 21280, Turkey"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Greg M.","family":"Arndt","sequence":"additional","affiliation":[{"name":"Lowy Cancer Research Centre, Children\u2019s Cancer Institute, UNSW Sydney, Sydney, NSW 2031, Australia"},{"name":"ACRF Drug Discovery Centre for Childhood Cancer, Children\u2019s Cancer Institute Australia for Medical Research, Lowy Cancer Research Centre, UNSW Sydney, Sydney, NSW 2052, Australia"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Glenn M.","family":"Marshall","sequence":"additional","affiliation":[{"name":"Lowy Cancer Research Centre, Children\u2019s Cancer Institute, UNSW Sydney, Sydney, NSW 2031, Australia"},{"name":"Kids Cancer Centre, Sydney Children\u2019s Hospital, Randwick, NSW 2031, Australia"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-9300-4737","authenticated-orcid":false,"given":"David StC.","family":"Black","sequence":"additional","affiliation":[{"name":"School of Chemistry, The University of New South Wales, Sydney, NSW 2052, Australia"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-8784-860X","authenticated-orcid":false,"given":"Belamy B.","family":"Cheung","sequence":"additional","affiliation":[{"name":"Lowy Cancer Research Centre, Children\u2019s Cancer Institute, UNSW Sydney, Sydney, NSW 2031, Australia"},{"name":"School of Women\u2019s and Children\u2019s Health, UNSW Sydney, Sydney, NSW 2052, Australia"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-0951-9621","authenticated-orcid":false,"given":"Naresh","family":"Kumar","sequence":"additional","affiliation":[{"name":"School of Chemistry, The University of New South Wales, Sydney, NSW 2052, Australia"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2021,9,22]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"2318","DOI":"10.1158\/1078-0432.CCR-06-2672","article-title":"Vorinostat for treatment of cutaneous manifestations of advanced primary cutaneous T-cell lymphoma","volume":"13","author":"Mann","year":"2007","journal-title":"Clin. 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