Identification and synthesis of the sex pheromone of the passionvine mealybug, Planococcus minor (Maskell).

The sex pheromone of the mealybug, Planococcus minor was isolated by fractionation of crude pheromone extract obtained by aeration of virgin females. The pheromone was identified as the irregular terpenoid, 2-isopropyl-5-methyl-2,4-hexadienyl acetate, by mass spectrometry, microchemical tests, and (1)H NMR spectroscopy. The stereochemistry of the pheromone was assigned as (E) by comparison with synthetic standards of known geometry. The compound was highly attractive to males in laboratory bioassays, whereas the (Z)-isomer appeared to antagonize attraction.