Prorocentin-5:\nA Cytotoxic Polyketide from the Benthic\nMarine Dinoflagellate <i>Prorocentrum lima</i>

Prorocentrin-5 (<b>1</b>) was isolated from the\nbenthic marine\ndinoflagellate <i>Prorocentrum lima</i>. A combination of\nNMR spectroscopy, quantum chemical calculations, and chemical reactions\nwas then employed to elucidate its molecular structure, including\nthe configurations of all stereogenic centers. In cytotoxicity assays,\nprorocentin-5 exhibited potent activity against the HCT-116 and Neuro2a\ncell lines, with IC<sub>50</sub> values of 4.4 and 2.8 μM, respectively.\nFurthermore, <b>1</b> increased the apoptotic cell population\nand induced cell cycle arrest, leading to the accumulation of cells\nin the S or G2/M phase and an accompanying decrease in the G0/G1 phase\nin HCT-116, Neuro2a, and HepG2 cells.