Sex pheromone biosynthesis in Mamestra brassicae l. (lepidoptera: noctuidae); stereochemistry of the Δ11desaturation

Abstract
(11S, 12R)-and (11R, 12S)-[2H14]palmitic acids 1 are converted in the pheromone gland of the moth Mamestra brassicae into the [2H11]- or [2H13]-hexadec-11-enyl acetates 2 by a formal syn-elimination of the C(11)-HR and C(12)-HR hydrogen atoms; this characterises the unique Δ11 desaturase from insects as closely related to the Δ9 desaturases from mammals, plants and bacteria.