The brown-banded cockroach has been the model in many studies about sex pheromones. Cockroaches rely on pheromones for many reproductive behaviours, including bringing the sexes together for mating. Their sex pheromones can be divided into two categories: cuticular compounds that elicit sexual responses after the sexes contact and volatile compounds that act over a distance. The female brown-banded cockroach emits a sex pheromone that attracts males. Charlton and colleagues isolated and identified the pheromone as 5-(2,4-dimethylheptanyl)-3-methyl-2
H-pyran-2-one which they refer to as supellapyrone. This sex pheromone can be synthesized by direct coupling of a brominated pryoned with an alkylzanic reagent. The stereochemistry of the natural pheromone was assigned by a combination of synthesis, chiral gas chromatography, and electrophysiological measurement. They key step in synthesizing the three stereoisomers of this pheromone is employing lipase-catalyzed desymmetrization or enantiomer separation of syn- or anti-2,4-dimethylpentane-1,5-diol. Supellapyrone has four configurations but female brown-banded cockroaches can only produce the RR isomer. In an experiment by Gemono and colleagues they found that the males are attracted to the RR isomer but they are also highly attracted to the SR isomer. The regulation of the female sex pheromone production, calling behaviour and release is regulated directly and indirectly by the corpora allata and
juvenile hormone. Smith and Schal came to this conclusion because both pheromone production and calling failed to occur after allatectomy; both pheromone production and calling could be restored by a corpora allata implantation or treatment with juvenile hormones; applications of a juvenile hormones to intact females advanced the age of pheromone production and NCA-I
transection, which activates the copora allata in other cockroaches, advanced the age of pheromone production and calling. Oöcyte growth in the brown-banded cockroach correlated with corpora allata activity
in vitro. Ovariectomies were conducted: both pheromone production and calling were unaffected by either nymphs or adults, this was done to demonstrate that the ovaries do not mediate in the regulation of pheromone production. Calling ceases in an adult female after mating and does not resume throughout the duration of the insects life. Calling was suppressed and oöcyte growth was stimulated by the presence of a
spermatophore, by the implantation of a spermatophore and by mating with vasectomized males. Odthecal deposition in females mated with vasectomized males caused calling to resume. ==References==