Two new drimane sesquiterpenes isolated from <i>Drimys winteri</i> (Canelo). Antifungal activity and molecular docking effect of winterdial against <i>Botrytis cinerea</i>

Drimys winteri (Canelo) is an endemic tree of Chile, belonging to the Winteraceae family, with significant ethnocultural importance among the Mapuche people. Recently, the antifungal activity of drimenol (<b>1</b>) and polygodial (<b>2</b>), the main drimane sesquiterpenes isolated from Canelo, against <i>Botrytis cinerea</i>, the fungus responsible for gray mould disease, has been demonstrated. In this study, we report the isolation and subsequent characterisation of two new sesquiterpenes: a drimane sesquiterpene with a lactone structure (<b>4</b>), and a novel sesquiterpene dialdehyde (<b>6</b>), along with three known compounds. Their structures were elucidated through comprehensive analysis of spectroscopic data. Additionally, we evaluated the antifungal activity of winterdial and the ethyl acetate fraction against <i>Botrytis cinerea</i>. The results demonstrated that both compounds moderately inhibit the mycelial growth of the fungus. Finally, a molecular docking analysis was conducted to gain insights into the potential mechanism of action of winterdial (<b>5</b>).