Total synthesis of aculeatins A and B via a tethered oxa-Michael approach

A stereocontrolled total synthesis of aculeatins A and B has been achieved in eight steps and in 15% overall yield. The key feature of this synthetic approach is the application of a Marouka allylation and tethered intramolecular oxa-Michael reaction to install the required stereocentres on the tetrahydropyran ring.