Green Semisynthetic Cascade to Ligstroside, Ligstroside Aglycone, and Oleocanthal

Ligstroside, ligstroside aglycone, and oleocanthal are extra virgin olive oil (EVOO) bioactive phenols poorly represented in olive leaves. Semisynthetic pathways to achieve them, starting with largely available natural precursors, are proposed as alternative solution with respect to their low effective extraction or total synthesis. In the present work, we propose the first green chemocatalytic method to obtain, in the same semisynthetic cascade, ligstroside, ligstroside aglycone, and oleocanthal starting from oleuropein. The sustainability of the method was assessed by building the synthesis trees, while the green credentials of each step were analyzed through the CHEM21 toolkit, thus allowing consequent considerations on the large-scale feasibility.