Marine Drugs (May 2021)

Antimicrobial Terpenoids from South China Sea Soft Coral <i>Lemnalia</i> sp.

  • Xia Yan,
  • Han Ouyang,
  • Wei Wang,
  • Jing Liu,
  • Te Li,
  • Bin Wu,
  • Xiaojun Yan,
  • Shan He

DOI
https://doi.org/10.3390/md19060294
Journal volume & issue
Vol. 19, no. 6
p. 294

Abstract

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Chemical investigation of the South China Sea soft coral Lemnalia sp. afforded 13 structurally diverse terpenoids, including three new neolemnane sesquiterpene lineolemnenes E–G (1–3); a new aristolane-type sesquiterpenoid, 2-acetoxy-aristolane (4); four new decalin-type bicyclic diterpenes, named biofloranates A−D (5−8); a new serrulatane, named euplexaurene D (9); and a new aromadendrane-type diterpenoid cneorubin K (10), together with three known related compounds (11−13). The structures of the new compounds were elucidated by NMR spectroscopy, the Mosher’s method, and ECD analysis. Compounds 1–13 were tested in a wide panel of biological assays. Lineolemnene J (3) showed weak cytotoxicity against the CCRF-CEM cancer cell line. The isolated new diterpenes, except euplexaurene D (9), demonstrated moderate antimicrobial activity against Bacillus subtilis and Staphylococcus aureus with a MIC of 4−64 μg/mL. Compound 2 exhibited a mild inhibitory effect against influenza A H1N1 virus (IC50 = 5.9 µM).

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