Pinnatifidenyne-Derived Ethynyl Oxirane Acetogenins from Laurencia viridis

Red algae of Laurencia continue to provide wide structural diversity and complexity of halogenated C acetogenin medium-ring ethers. Here, we described the isolation of three new C acetogenins (3–5), and one truncated derivative (6) from Laurencia viridis collected on the Canary Islands. These compounds are interesting variations on the pinnatifidenyne structure that included the first examples of ethynyl oxirane derivatives (3–4). The structures were elucidated by extensive study of NMR (Nuclear Magnetic Resonance) data, J-based configuration analysis and DFT (Density Functional Theory) calculations. Their antiproliferative activity against six human solid tumor cell lines was evaluated.
This work was supported by grant CTQ2014-55888-C03-01-R (Ministry of Economy and Competitiveness of Spain, MINECO). A.M.-A. and C.R.d.V. acknowledge MINECO for a Ph.D. scholarship and O.M.-F. thanks ULL for a grant.