New Isocoumarins from the Marine Fungus <i>Phaeosphaeriopsis</i> sp. WP-26

Abstract

Five new isocoumarins, phaeosphaerins A–E (1–5), were isolated from the fermentation broth of the marine fungus Phaeosphaeriopsis sp. WP-26, along with one known isocoumarin, 6,8-dihydroxy-7-methoxy-3-methylisocoumarin (6), and two known pimarane-type diterpenes, diaportheins A (7) and B (8). Their structures were elucidated via NMR experiments, X-ray diffraction analysis, and comparison of the experimental and computed ECD curves. Compounds 1–7 displayed weak neuroprotective effects against H2O2-induced damage in SH-SY5Y cells. Moreover, compound 8 showed cytotoxicity against BEL-7402, SGC-7901, K562, A549, and HL-60 cell lines.

Keywords

• isocoumarins
• marine fungus
• <i>Phaeosphaeriopsis</i> sp.
• neuroprotective effect
• cytotoxicity