Total Synthesis and Biofilm Inhibitory Studies of Knightine Cembranoid Diterpenes.

We report the first total synthesis of the cembranoid diterpenes knightol, knightal, and knightol acetate isolated from the Caribbean Sea Whip, Eunicea knighti. Highlights of the synthesis include leveraging farnesol as a feedstock starting material, a late-stage Shi epoxidation, and a penultimate Horner-Wadsworth-Emmons macrocyclization. Biological studies reveal modest biofilm inhibitory activity against Staphylococcus aureus for the most active member, (-)-knightol.