A highly purified preparation of juvenile hormone from the silk moth Hyalophora cecropia L

Total synthesis of the racemic form of the second juvenile hormone (methyl 12-homojuvenate) from the cecropia silk moth

Methyl cis-10-epoxy-3,7,11-trimethyl-trans,trans-2,6-tridecadienoate has been stereoselectively synthesized in 12 steps starting from methyl trans-gamma-bromo-beta,beta-dimethylacrylate and 1-acetyl-1-methylcyclopropane. The final product proved to be identical with the second, less abundant juvenile hormone (methyl 12-homojuvenate) isolated from the Cecropia silk moth. The biological activities of the compound were evaluated in various insects.

Bombyx mori development: the context for its endocrine system

Quantitative data on neurohormones (brain-hormones) steroïd hormones, juvenile hormones, in an insect : Bombyx mori are outlined. The variations of hormonal contents throughout larval and pupal development, in eggs and ovocytes are analyzed.

[Effect of injection of synthetic Hyalophora cecropia juvenile hormone in Locusta migratoria L]

The synthetic racemic C18 Hyalophora cecropia juvenile hormone (JH-I) is injected at does of between 10 and 200 mug/animal at the end of the fourth instar of Locusta migratoria. The effects on mortality, length of the fourth and fifth instars, pigmentation and morphogenesis are reported. Higher doses of JH-I produce a higher mortality than lower doses. But mortality can also occur following the injection of oil which sometimes takes place only a few hours before the ecdysis. In no case is JH-I able to shorten the length of the instar. Many animals moult at the same time as the controls, but some of them, both in the fourth and fifth instars, show an important increase in the length of the instar because of an inhibition of the ecdysis. The effect of JH-I on pigmentation is very important and doses higher than 50 mug/animal present a greater effect than an implantation of one pair of corpora allata, both on the number of insects which turn green and on the intensity of this green pigmentation. At the metamorphosis the larvae injected with JH-I produce imperfect imagos and supernumerary larvae, the number of which depends upon the dose. Nevertheless the morphogenetic effect is considerably lower than that of one pair of corpora allata. We have reason to think that this is only due to the time of injection and not to the activity on morphogeneis of the injected hormone. JH-I is injected at the dose of 200 mug in young females which were allatectomized beforehand to prevent oocytes maturation. The hormone completely counter-balances the lack of the corpora allata and some days after the injection the oocytes are in the same state of development as those of the controls. All the results indicate that the synthetic racemic C18 juvenile hormone of Hyalophora cecropia shows a quite similar activity to the secretion of the corpora allata on Locusta migratoria although it has been said for some time that this hormone was not the principal one in locusts.