S-methoprene

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...

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. 

FipronU has high intrinsic activity against a wide range of animal health pests and has become the standard treatment for flea and tick control on domesticated animals. Cat fleas Ctenocephalides fdis) are extremely sensitive to fipronil [128] when apphed as either a spray [129] or a spot-on [130] formulation to companion animals. Fipronil is also highly active on ticks [131,132] and has been shown to reduce the transmission of the tick-home causative agents of canine diseases [133, 134]. Fipronil has also been shown to control biting lice on both dogs and cats [135, 136], Fipronil is applied as both a spray and a spot-on treatment as well as a combination product with s-methoprene. 

Wang, I.-H. Subramanian, V. Moorman, R. Ko, J. Johnson, D. A validated reversed-phase HPLC method for analyzing pyrethrins, piperonyl butoxide, and (S)-methoprene in pesticide formulations, LC.GC, 1999,17, 260-275. 

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. 

Ankley, G.T., J.E. Tietge, D.L. DeFoe, K.M. Jensen, G.W. Holcombe, E.L. Durhan, and S.A. Diamond. 1998. Effects of ultraviolet light and methoprene on survival and development of Rana pipiens. Environ. Toxicol. Chem. 17 2530-2542. 

Retinoic Acid Receptor. Most of the biological effects of retinoids are mediated through the retinoic acid receptor (RAR) and the retinoid X receptor (RXR). Both all-/ran.s-retinoic acid and 9-d.v-rctinoic acid serve as agonists of RAR, while only 9-d.v-rctinoic acid functions as an agonist of RXR. The functional RAR exists as a heterodimer with RXR, while functional RXR exists as a homodimer. Methoprene is a juvenile hormone III analogue that mimics the activity of this insect hormone. 

Methoprene is the common name for a racemic mixture of two enantiomers (R and S in a ratio of 1 1). The activity of the compound as a juvenile hormone mimic is restricted to the S enantiomer. 

Both methoprene and JH are small molecules and by themselves will not elicit an immune response. They must be covalently bound to a large molecule, such as a protein, which facilitates presentation of the small molecule to a mammal s immune system. Such small molecules, when bound to carriers for immunological purposes, are known as haptens. 

Female, New Zealand white rabbits were each immunized with an emulsion of the methoprene immunogen (200 fig per animal, 53 molecules of methoprene per molecule of protein) in 250 fib phosphate buffered saline and 250 fib Freund s complete adjuvant. A booster shot of the immunogen (200 fig per animal) in Freund s incomplete adjuvant was given to each animal one month after the initial immunization and again two weeks after the first booster shot. Rabbit anti-methoprene antiserum was collected and used to develop a competition enzyme-linked immunosorbent assay or cELISA for methoprene. 

Pyrethrins and PBO in combination with methoprene showed lOO ft control of feline fleas 35 days after treatment, with a satisfactory residual effect up to 2 months (Donahue, 1992). In addition (here is evidence that PBO is an 1GR in its own right. In a laboratory study PBO added lo three major cotton plant al 1 Biochemical s in the diet of tobacco bud worm larvae significantly decreased the growth rate of the 5-day-old larvae, and was found to be toxic to the 1- and 3-day-old larvae (Hey din t i u/.. 1988). 

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). 

Juvenile hormone agonists as pesticides Methoprene is a juvenile hormone mimic preventing metamorphosis and is used to control a wide variety of insects, especially Diptera and Pharaoh s... 

Wang, S., Allan, R.D., Hill, A.S., Kennedy, 1.1C (2002) Rapid enzyme immunoassays for the detection of carbaryl and methoprene in grain, Journal of Environmental Science Health, B37, 521-532... 

Rotenone is an alkaloid botanical pesticide isolated from plants (Denis sp. or Lonchocarpus sp.). It blocks mitochondrial electron transport. It is associated with dermatitis and mucous membrane irritation in humans and is very potent in fish. In humans, intoxication is rare but when present is directed toward the respiratory system. Rotenone is used as a topical ectoparasiticide. As mentioned in the text, it has been implicated as possibly having a role in Parkinson s disease. The newest and by far safest class of insecticides available today are the insect growth inhibitors, such as methoprene (PreCor ), and chitin synthesis inhibitors, such as lufenuron (Program ). 

Methoprene (marketed as Precor), an insect juvenile hormone mimic used in flea control products for pets, works by preventing the development of flea eggs and larvae. The effective form of methoprene, shown here, is optically active. Locate the stereogenic center and determine its configuration (R,S). 

In contrast to its failure to catalyze the tritiation of the iron carbonyl-protected methoprene (21. Section 4.1.1 above), Wilkinson s catalyst was effective in the selective tritiation of the olefinic double bond of the analogously protected hydroprene (89) to give [ H]hydroprene (90) at a specific activity of 65.5 Ci/mmol after deprotection, as shown in Figure 4.27. ... 

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