Growth regulators, methoprene

Ellgaard, E.G., J.T. Barber, S.C. Tiwari, and A.L. Friend. 1979. An analysis of the swimming behavior of fish exposed to the insect growth regulators, methoprene and diflubenzuron. Mosquito News 39 311-314. 

Harmon, M., M.F. Boehm, R.A. Heyman and D.J. Mangelsdorf. Activation of mammalian retinoid X receptors by the insect growth regulator methoprene. Proc. Natl Acad. Sci. USA 92 6157-6160, 1995. 

Amin, A.M. and White, G.B. (1984) Resistance potential of Culex quinquefasciatus against insect growth regulators methoprene and diflubenzuron. Entomologia Experimentalis et Applicata 36, 67-76. 

Kawada, H. and Hirano, M. (1996) Insecticidal effects of the insect growth regulators methoprene and pyriproxyfen on the cat flea (Siphonaptera Pulicidae). Journal of... 

Samson, P.R., Parker, R.J. and Hall, E.A. (1990) Efficacy of the insect growth regulators methoprene, fenoxycarb and diflubenzuron against Rhyzopertha dominica (F.) (Coleoptera Bostrichidae) on maize and paddy rice. Journal of Stored Products Research 26, 215-221. 

Methoprene is an insect growth regulator and it is also used as an insecticide for cockroaches. The enantioselective isomerization of 7-methoxygeranylamine in the presence of [Rh((+)-BINAP)2]+ followed by acid hydrolysis provides the intermediate, 7-methoxycitronellal, in high yield with high optical purity (97%, 98% ee, Scheme 6).9 Alternatively, methoxylation of ( -citronellalenamine (98% ee) with methanol in the presence of 97% sulfuric acid followed by hydrolysis gives 7-methoxycitronellal in 79% yield without racemiza-tion (Scheme 6).9... 

The pest mosquito Aedes nigromacul Ls of the vast San Joaquin valley of California went resistant to organochlorines by 1951, to parathion by 1960, to fenthion by 1965, and to chlorpyrifos (Dursban) by 1970. At present reliance is placed on larvicidal oils, the juvenile-hormone mimic methoprene (Altosid) and the insect growth regulator diflubenzuron (Dimilin), — and on better management of surplus irrigation water. Residual sprays for housefly control, at first so spectacular with the organochlorines, had to move into the OP compounds, which were then knocked out in... 

The multiresistant strains now extant also show a certain cross-tolerance, but not resistance, to the third-generation insecticides such as the juvenile-hormone mimics and other so-called insect growth regulators, as was found in strains of the housefly, flour beetle and tobacco budworm. Resistance to the JH mimic methoprene and Monsanto-585 has been induced by laboratory selection of Culex taxsalis (28) and Culex pipiens (29), and to Monsanto-585 in Culex quinquefasstatus (30). Whatever insect or IGR is chosen, the result of exposure to selective doses in successive generations is usually the development of resistance, repeating our previous experience with chemosterilants, and the... 

Methoprene simulates a mosquito growth-regulating hormone. When the mosquito larvae are exposed to this compound, the insects fail to change to an adult. This compound is specific to mosquitoes and is nontoxic and environmentally friendly. 

Compounds that mimic the action of JHs could also be used as insecticides. In fact, numerous JH analogs were derived among which methoprene. This ligand, used commercially as an insect growth regulator, closely resembles JHs, but lacks the epoxide func-... 

Methoprene is a long chain hydrocarbon ester active as an insect growth regulator. It is effective against several insect species. Formulations include slow-release briquets, sprays, foggers, and baits. 

Besides aroma chemicals, we are supplying key intermediates for the synthetic insect growth regulators, (S)-3,7-dimethyl-l-octanal 18a and (S)-7-methoxy-citronellal 18b, on 100 ton scales each. Hydropren 19a is effective for mosquitoes and Methopren 19b is used for controlling cockroach, where only (S)-forms are active (Fig.3). 

Figure 6.5 Contour plot showing the distribution of Altosand granules in a coastal salt-marsh. Altosand is a commercial formulation of S -methoprene, an insect growth regulator used to control mosquitoes...

Garg, R.C. and Donahue, W.A. (1989) Pharmacologic profile of methoprene, an insect growth regulator, in cattle, dogs, and cats. Journal of the American Veterinary Medicine Association 194, 410-412. 

An interesting application of this assay revealed that although the insect growth regulator S-methoprene had relatively high values for 96-h LC50 and 96-h EC50, the values for metabolites produced by photolysis and hydrolysis were lower (La Clair et al. 1998) in particular those in which hydrolysis of the ester had occurred displayed serious eye deformations. 

Methoprene was the first insect growth regulator to receive formal regulatory status from the US Environmental Protection Agency. Field trials at rates of 30-100 g/acre in an area infested with the eastern hemlock looper, Lambdim fiscellaria, resulted in an economic reduction of pupae and adults (Menn and Pallos,... 

Juvenile hormones are one of three types of internal regulators of insect growth and metamorphosis. These hormones are synthesized and released in a regulated way into the hemolymph. Immature larvae require these hormones to progress through the regular larval stages. Methoprene disrupts these hormonal processes and prevents metamorphosis. 

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