Hydrogenation derivatives of neo-clerodanes and their antifeedant activity

Hydrogenation of some natural neo-clerodanes on 10% Pd/C resulted in the sa turation of the furan ring and in some cases hydrogenolysis of the epoxide system and or gamma-lactone ring. Overall, reduction of the furan ring foun d in the natural compounds resulted in a decrease in the antifeedant activi ty of the compounds against the lepidopteran pests, Heliocoverpa armigera a nd Spodoptera frugiperda. However, two of the most active derivatives had b oth the furan ring and the lactone ring hydrogenated but the epoxide intact .