Arylpyridyl-thiosemicarbazones: A new class of anti-juvenile hormones active against Lepidoptera

Summary

A new class of anti-juvenile hormone agents is described. Active anti-juvenile hormone compounds were either diazine thiosemicarbazones or aryl substituted pyridyl thiosemicarbazones, synthesized from substituted benzaldehydes. While many analogs in these classes showed feeding and growth inhibition in a variety of insects, a select group caused formation of precocious pupal characteristics inAgrotis ipsilon (black cutworm) andHeliothis virescens (tobacco budworm) and black cuticle and precocious pupae inManduca sexta (tobacco hornworm). They were active only by diet incorporation. The symptoms of precocious development could be reversed by co-administration of a juvenoid. One of the active compounds was shown to inhibit juvenile hormone biosynthesis in vitro by corpora allata of the cockroachDiploptera punctata. However, none of the compounds were active inhibitors of purified chicken liver prenyl transferase.