Cytotoxic components from the Xisha sponge Fascaplysinopsis reticulata

A new dolabellane diterpenoid, clavirolide H (1), together with eleven known compounds, including two dolabellane diterpenoid (2 and 3), a rare cavernosine-type C₁₇ γ-lactone terpenoid (4), a diketopiperazine (5) and seven sterols (6-12), were isolated from the Xisha sponge Fascaplysinopsis reticulata. Their structures were elucidated by extensive spectroscopic analysis, and the four types of compounds of the above isolates were reported from the genus Fascaplysinopsis for the first time. Selected compounds 1, 4-6 and 9-12 were evaluated for cytotoxic activities against K562, HL-60, Hela, HCT-116, A549, L-02 and BEL-7402 cell lines. Compounds 4-6 and 10-12 showed potent cytotoxicitives against HL-60 with IC₅₀ values ranging from 8.8 to 12.4 μM. Compounds 4 and 5 exhibited weak cytotoxic activities against HeLa with IC₅₀ of 20.7 and 27.4 μM, and 5 also has moderate cytotoxicity against HCT-116 with IC₅₀ of 16.3 μM.[Figure: see text].