Phyllofenones F-M, Scalarane Sesterterpenes from the Marine Sponge .

Eight new scalarane sesterterpenes, phyllofenones F-M (-), together with two known analogues, carteriofenones B and A (-), were isolated from the marine sponge collected from the South China Sea. The structures of these compounds were determined based on extensive spectroscopic and quantum chemical calculation analysis. The antibacterial and cytotoxic activity of these compounds was evaluated. Among them, only compounds and displayed weak inhibitory activity against and , with MIC values of 16 μg/mL and 8 μg/mL, respectively. Compounds - exhibited cytotoxic activity against the HeLa, HCT-116, H460, and SW1990 cancer cell lines, with IC values ranging from 3.4 to 19.8 μM.