This article describes a cost-effective and scalable synthetic method for the preparation of ent-kaurane diterpenoids from commercially available stevia sweeteners. By enabling the efficient synthesis of ent-kaurenol, this approach facilitates access to a wide variety of structurally diverse and stereochemically defined kaurane derivatives, including annomosin A and annoglabasin A.

A practical and cost-effective method is developed for preparing steviol from commercially available stevia sweetener. As steviol can be efficiently converted into ent-kaurenol, this strategy enables the large-scale synthesis of ent-kaurenol and its derivatives. To demonstrate the versatility of ent-kaurenol as a synthetic intermediate, several derivatives are synthesized, including carboxylic acid and diol compounds with controlled C-16 stereochemistry. This methodology is applied to the synthesis of the ent-kaurane dimer annomosin A, isolated from Annona squamosa, and the bioactive diterpene annoglabasin A, from Annona glabra. The approach allows access to structurally diverse kaurane derivatives with defined C-16 stereochemistry and is readily extendable to the synthesis of kaurane dimers. Given the limited understanding of the biosynthetic pathways and biological functions of natural kaurane dimers, this synthetic strategy provides a valuable platform for future structural and functional investigations.