Stereoselective Synthesis, Configurational Assignment and Biological Evaluations of the Lipid Mediator RvD2 n-3 DPA .

Herein we report the first total synthesis of RvD2 , an endogenously formed mediator biosynthesized from the omega-3 fatty acid n-3 docosapentaenoic acid. The key steps are the Midland Alpine borane reduction, Sonogashira cross-coupling reactions, and a Z-selective alkyne reduction protocol, yielding RvD2 methyl ester in 13 % yield over 12 steps (longest linear sequence). The physical property data (UV chromophore, chromatography and MS/MS fragmentation) of the synthetic lipid mediator matched those obtained from biologically produced material. Moreover, synthetic RvD2 also carried the potent biological activities of enhancing macrophage uptake of Staphylococcus aureus and zymosan A bioparticles.