Insect Antifeedant Ryanodane Diterpenes from <i>Persea indica</i>

Abstract

The new ryanodane diterpenes cinnzeylanone, ryanodol 14-monoacetate, and epi -cinnzeylanol have been isolated from Persea indica (Lauraceae). The structure of cinnzeylanone has been determined by X-ray analysis. These compounds proved to be antifeedants against Spodoptera litura . Cinnzeylanol and ryanodol were the most active antifeedants of this plant, with a range of activity close to that of ryanodine. This is the first report on the antifeedant effects of this class of diterpenes. Their structure−activity relationships and possible mode of action are discussed. Keywords: Ryanodane diterpenes; cinnzeylanone; ryanodol 14-monoacetate; epi -cinnzeylanol; antifeedants