Highly Substituted Benzophenone Aldehydes and Eremophilane Derivatives from the Deep-Sea Derived Fungus Phomopsis lithocarpus FS508.

Five new benzophenone derivatives named tenellones D⁻H ( 1 ⁻ 5 ), sharing a rare naturally occurring aldehyde functionality in this family, and a new eremophilane derivative named lithocarin A ( 7 ), together with two known compounds ( 6 and 8 ), were isolated from the deep marine sediment-derived fungus Phomopsis lithocarpus FS508. All of the structures for these new compounds were fully characterized and established on the basis of extensive spectroscopic interpretation and X-ray crystallographic analysis. Compound 5 exhibited cytotoxic activity against HepG-2 and A549 cell lines with IC ₅₀ values of 16.0 and 17.6 μM, respectively.