Ahmed A.FCheng YCHANG-FENG DAISheu J.-H.2021-07-172021-07-17202114203049https://www.scopus.com/inward/record.uri?eid=2-s2.0-85107351764&doi=10.3390%2fmolecules26113276&partnerID=40&md5=366ace8033df5b5851a0f8ab25a5f837https://scholars.lib.ntu.edu.tw/handle/123456789/571832Three new polyoxygenated diterpenoids with a rare 4-isopropyl-1,5,8a-trimethylperhydrophenanthrane structure of the klysimplexane skeleton, briarols A-C (1-3), and one eunicellin-based diterpenoid, briarol D (4), were isolated from Briareum violaceum, a gorgonian inhabiting Taiwanese waters. The chemical structures of these compounds were determined by employing extensive analyses of NMR and high-resolution electrospray ionization mass spectrometry (HRESIMS) data. Metabolites 1-3 were found to possess the rarely found skeleton of the diterpenoid klysimplexin T. All isolated compounds showed very weak cytotoxic activity against the growth of three cancer cell lines. A plausible biosynthetic pathway for briarols A-C from the coexisting eunicellin diterpenoid briarol D (4) was postulated. ? 2021 by the authors. Licensee MDPI, Basel, Switzerland.Briareum violaceum; Briarol; Eunicellin; Gorgonian; Klysimplexane[SDGs]SDG3[SDGs]SDG14antineoplastic agent; diterpenoid; eunicellin; proton; animal; Anthozoa; chemistry; drug design; electrospray mass spectrometry; HT-29 cell line; human; IC50; medicinal chemistry; metabolism; neoplasm; nuclear magnetic resonance spectroscopy; powder; procedures; Taiwan; tumor cell line; water management; water pollutant; Animals; Anthozoa; Antineoplastic Agents; Cell Line, Tumor; Chemistry, Pharmaceutical; Diterpenes; Drug Design; HT29 Cells; Humans; Inhibitory Concentration 50; Magnetic Resonance Spectroscopy; Neoplasms; Powders; Protons; Spectrometry, Mass, Electrospray Ionization; Taiwan; Water Pollutants, Chemical; Water Purificationjournal article10.3390/molecules26113276340716602-s2.0-85107351764