Haterumaimides J and K, potent cytotoxic diterpene alkaloids from the ascidian Lissoclinum species
Two unique cytotoxic diterpene alkaloids, haterumaimides J and K, were isolated from the ascidian Lissoclinum sp. Their structures were elucidated by an extensive analysis of spectral data. Haterumaimides J and K showed potent cytotoxicity against P388 cells, with IC50 values of 0.23 ng/mL and 0.45 ng/mL, respectively.