Enantioselective formal synthesis of (-)-ovalicin using quinic acid as a chiral template

The key intermediate 18 for the synthesis of (-)-ovalicin was synthesized using (-)-quinic acid as the chiral source, through a series of stereocontrolled and efficient chemical reactions, thus establishing a new, formal synthesis of the natural target. The featuring spirocyclic epoxide function has been installed by internal Williamson ether synthesis using the functionalities originally present at C-1 of (-)-quinic acid after the appropriate adjustments required to introduce the necessary functionality at C-2.