Total synthesis of the anti-inflammatory lipid mediator Resolvin E2

The total synthesis of Resolvin E2, an endogenous lipid mediator of the resolution of inflammation derived from eicosapentaenoic acid, has been achieved. The chiral hydroxy-groups at C5 and C18 were generated in a simple, efficient, and environmentally friendly manner via an asymmetric Noyori transfer hydrogenation in water using sodium formate as a reducing agent. Pd⁰/Cu^I Sonogashira couplings of the three key fragments and Zn(Cu/Ag) reduction completed the synthesis of Resolvin E2.