Juvenile hormone analog, insect control

Phvtoluvenolds. Wigglesworth (JL) demonstrated that a hormone secreted by the insect corpora allata was responsible for the control of differentiation in immature insects and reproduction in adult female insects. Williams (3) prepared an active extract of this hormone from adult male cecropia moths and called it "juvenile hormone". We were able to derive sufficient knowledge of the chemistry of the juvenile hormone from the study of the active cecropia extract to synthesize JH III Q). Seven years later its presence as a natural hormone in the tobacco hornworm was confirmed Ci). Three other analogous juvenile hormones (JH 0, I, II) have been found to occur only in lepidoptera (5, ., 2.) (Figure 1). Juvenile hormone III is the principal juvenile hormone of insects and has been demonstrated in all of the insect taxa investigated. 

Methoprene, a juvenile hormone analog, is structurally similar to insect juvenile hormones (Figure 4.11) such as juvenile hormone III. It is used for control of mosquitoes (floodwater mosquitoes, 2-4 instars), cigarette beetles, horn flies, fungus gnats (on mushroom), fleas, etc. The oral LD50 for methoprene in rats is >34,600 mg/kg. 

Juvenile Hormone Analogs and Anti-JuvenUe Hormone Agents for Insect Control... 

These inhibitors would be classified as anti-juvenile hormones and could be expected to show selective action on insects as a class. Such analogs are by no means just around the corner since at least two important properties that they should possess may be difficult to build into small organic molecules suitable for pest control. These properties are the ability to withstand general metabolic inactivation while retaining the ability to inhibit irreversibly the target enzymes of the corpus allatum and the property to accumulate selectively in corpora allata, a physically small target, so as to offset dilution in the general body cavity. 

Herbert Oberlander coordinated the section that features chapters on sac-specific selection using chimeric genes potential applications of neuroendocrine research to insect control insect cuticle structure and metabolism molecular aspects of immune mechanisms in insects molecular genetics of nerve insensitivity resistance to insecticides and inhibition of juvenile hormone esterase by transition-state analogs. 

In addition to the natural compounds, many synthetic analogs have high activities in biological tests, especially juvenile hormone activity. Such environmentally non-damaging biological substances can be used for the control of insect pests. 

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