Amphirionin-5, a novel linear polyketide from a cultured marine dinoflagellate Amphidinium species with a potent cell proliferation-promoting activity

A novel linear polyketide, amphirionin-5 (1), has been isolated from the cultivated algal cells of the benthic dinoflagellate Amphidinium sp. (strain KCA09053), and the structure was elucidated on the basis of detailed analyses of 1D and 2D NMR data. Amphirionin-5 (1) resulted in a 282% increase in the proliferation of murine bone-marrow derived stromal ST-2 cells and 320% increase in the proliferation of murine osteoblastic MC3T3-E1 cells.