A compound with significant insect juvenile hormone activity was isolated from the plant, Macropiper excelsum . The chemical structure was determined by spectral methods to be 1-(3,4-methylenedioxyphenyl)-trans-3-decene(l), and confirmed by synthesis. The hormonally active substance applied topically to last (fifth)-instar nymphs of the milkweed bug ( Oncopeltus fasciatus ) induced a supernumerary metamorphosis at 30 μg. Higher doses were toxic.

MaleGrapholitha molesta hairpencil components are ethyltrans-cinnamate, mellein, methyl jasmonate, and methyl 2-epijasmonate. The natural behavioral effect elicited by hairpencil-displaying males during courtship in attracting sex-pheromone-releasing females from several centimeters away can be duplicated by mixtures of ethyltrans-cinnamate in various combinations with the other components.

A blend of ethyl trans-cinnamate, methyl 2-epijasmonate, methyl jasmonate, and (R)-(–)-mellein, identified from the hairpencils of male Oriental fruit moths, attracts sex pheromone-releasing females several centimeters away. The chemicals thereby duplicate the behavioral effect elicited by hairpencil-displaying males during courtship; the chemicals also produce the herbal scent emanating from the hairpencils.