Juvenile hormone mimics: Structure-activity relationships for Oncopeltus fasciatus

Four series of compounds have been tested for juvenile hormone (JH) mimic activity with Oncopeltus fasciatus. (1) Derivatives of methyl benzoate showed that activity is limited to terpenoid side chains, although, surprisingly, a C₅ homologue, the p-3,3-dimethylallyloxy derivative, is quite active. (2) Geraniol and simple esters which extend the chain up to C₆ were inactive, as were several more complex esters and ethers. (3) Compounds derived from farnesol by one carbon chain extension did not greatly increase activity. However, considerable activity was still present when the chain was lengthened by 5 carbons to produce ethyl geranylgeranate. Rearrangement of the unsaturated double bonds removes activity. Formation of ethoxy ethers by addition of ethanol to the double bonds increases activity considerably. (4) Conjugation of farnesol with cholesterol increases the activity.