Stereoselective synthesis of (−)-pironetin by an iterative Prins cyclisation and reductive cleavage strategy

A stereoselective synthesis of pironetin, a natural product which is highly immunosuppressive and shows remarkable plant growth regulatory and antitumoral activities, is described. The approach avails successfully the high stereoselection of Prins cyclisation. The route relies, in addition, on the reductive opening of cyclic ethers, olefin metathesis, and lithium acetylide displacement of tosylate