Inhibition of sex pheromone production in female lepidopteran moths by 2-halofatty acids.

Inhibition of sex pheromone production has been observed after topical treatment of pheromonal glands with DMSO solutions of 2-bromohexadecanoic acid, in three lepidopteran insects: Spodoptera littoralis, Thaumotopoea pityocampa, and Bombyx mori. It has been shown that this effect was brought about by action on the reductases and acetyltransferases of the final steps of the pheromones biosynthesis. Other halofatty acids, such as 2-fluoro- and 2-chlorohexadecanoic acids, were less active than the above bromoderivative whereas 2-bromotetradecanoic acid and 2-bromooctanoic acid exhibited activities quite comparable to the C-16 bromoacid. These results indicate that bromosubstitution is very important for this inhibitory action and chain length is of secondary importance.