Shikimate-Derived Meroterpenoids from the Ascidian-Derived Fungus <i>Amphichorda felina</i> SYSU-MS7908 and Their Anti-Glioma Activity

Glioma
is a clinically heterogeneous type of brain tumor with a
poor prognosis. Current treatment approaches have limited effectiveness
in treating glioma, highlighting the need for novel drugs. One approach
is to explore marine natural products for their therapeutic potential.
In this study, we isolated nine shikimate-derived diisoprenyl-cyclohexene/ane-type
meroterpenoids (1–9), including four
new ones, amphicordins A–D (1–4) from the ascidian-derived fungus Amphichorda felina SYSU-MS7908, and further semisynthesized four derivatives (10–13). Their structures were extensively
characterized using 1D and 2D NMR, modified Mosher’s method,
HR-ESIMS, NMR and ECD calculations, and X-ray crystallography. Notably,
amphicordin C (3) possesses a unique benzo[g]chromene (6/6/6) skeleton in this meroterpenoid family. In an anti-glioma
assay, oxirapentyn A (7) effectively inhibited the proliferation,
migration, and invasion of glioma cells and induced their apoptosis.
Furthermore, an in silico analysis suggested that
oxirapentyn A has the potential to penetrate the blood–brain
barrier. These findings highlight the potential of oxirapentyn A as
a candidate for the development of novel anti-glioma drugs.