Syntheses of the two optical isomers of the insect anti-juvenile hormone agent ethyl p-[2-(t-Butylcarbonyloxy)butoxy]benzoate (ETB) and their biological activities

Abstract

The optical isomers (9) and (13) of the insect anti-juvenile hormone, (�)-ethyl p-[2-(t-butylcarbonyloxy)butoxy]benzoate (ETB) (14), have been synthesized and their biological activities examined in the tobacco hornworm Manduca sexta. It was found that the observed anti-juvenile hormone activity at low dose levels and juvenile hormone activity at higher levels in the Manduca sexta, after topical treatment with the racemic mixture (14) is due entirely to the (–)-enantiomer (9), the (+)-enantiomer (13) being completely inactive.