Natural and unnatural A-seco terpenes from pulegone: Synthesis of galbanic acid and marneral revisited
We describe herein an improved chiral-pool strategy for assembling the core structure 3 (both antipodes) of various Aseco terpenoids that have allowed us to prepare natural galbanic acid [(-)-1] from (S)-(-)-pulegone [(-)-2]. Furthermore, we were able to