A concise route to the macrocyclic core of the rakicidins

An efficient synthesis of the macrolactone core of the rakicidins is described. The rakicidins are cytotoxic lipopeptides with interesting cancer cell selectivities including HIF-1-independent hypoxia-selective cytotoxicity and anti-invasive activity. Access to the core may now allow establishment of preliminary SAR and exploration of routes to several members of rakicidins.