Piperonyl butoxide

Parathion and other phosphorothionates must be bioactivated to the oxon derivatives in order to be toxic. This is mainly done by the CYP enzymes 

Source Based on data from Levine, B. and Murphy, S.D. 1977. Toxicol. Appl. Pharmacol., 40, 393-406. 

The oxidation, which is the bioactivation reaction, is inhibited by piperonyl butoxide, whereas the demethylation reaction catalyzed by glutathione transferase is not inhibited. Piperonyl butoxide is therefore an antagonist to methyl-parathion, but a synergist to most other pesticides, including carbamates and pyrethroids. Pyrethrins are very quickly detoxified by oxidation of one of the methyl groups, catalyzed by the CYP enzymes. 

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Piperonyl butoxide [51-03-6] is 5-[2-(2-butoxyethoxy)ethoxy]methyl-6-propyl-l,3-benzodioxole (11) d 1.04—1.07, vp 0.13 kPa at 25°C). The rat oral LD qS are 7500, 6150 mg/kg. Piperonyl butoxide is the synergist commonly used with natural pyrethrins in aerosol sprays. 

Gas ehromatography mass-mass aequisition was used for the pyrethroid determination. Pyrethroids investigated were Allethrin, Prallethrin, Tetramethrin, Bifenthrin, Phenothrin, X-Cyhalothrin, Permethrin, Cyfluthrin, Cypermethrin, Flueythrinate, Fsfenvalerate, Fluvalinate and Deltamethrin. Piperonyl butoxide, main synergist eompound for pyrethroid eompounds, was also studied. 

Insecticide Fliesa None Myristicin Piperonyl butoxide ... 

A number of synergists are used with pyrethrum to increase its toxicity. Most of the better ones, as far as flying insects are concerned, are of the methylene dioxyphenyl type. The best known of this type is piperonyl butoxide. 

Piperonyl butoxide increases the absolute toxicity of the four constituents of pyrethrum. 

Bates, Hewlett, and Lloyd (I) found that both piperonyl butoxide and SKF 525A, the ester of 2-diethylaminoethyl 2,2-diphenyl-w-pentanoate, synergized the action of pyrethrins on insects of species of the lesser mealworm beetles and houseflies but both antagonized the action of malathion. SKF 525A is known to increase the effects on mammals of drugs of various types and has been shown to synergize pyrethrins. 

Bates, Hewlett, and Lloyd (2) therefore studied the synergistic effects of some compounds related to 2-diethylaminoethyl 2,2-diphenyl-w-pentanoate on the insecticidal activity of pyrethrins. They found active compounds when a 2-diethylamino moiety was joined to the diphenylmethyl moiety through an ester, ketone, or ether linkage. However, none of the compounds investigated approached piperonyl butoxide in synergistic activity with pyrethrins. 

Piperonyl butoxide, a common potentiator of insecticide effects that inhibits microsomal enzymes, antagonized the toxic effects of methyl parathion in mice (Mirer et al. 1977). 

Isshiki K, Miyata K, Martsui S, et al. 1983. [Effects of post-harvest fungicides and piperonyl butoxide on the acute toxicity of pesticides in mice. Safety evaluation for intake of food additives. III]. 

Mirer FE, Levinl BS, Murphy SD. 1977. Parathion and methyl parathion toxicity and metabolism in piperonyl butoxide and diethyl maleate pretreated mice. Chem Biol Interactions 17 99-112. 

Insect strains resistant Cypermethrin Monooxygenase Piperonyl butoxide (PBO) <200... 

Note NaCh = sodium channel RF = resistance factor, which is LDjq resistant strain/LDjQ susceptible strain GABA = gamma amino butyric acid receptor PBO = piperonyl butoxide. 

In the search for safe insecticides, hundreds of products have been prepared and subjected to screening tests against insects. This paper presents information on six materials related to piperonyl butoxide, tested in combination with pyrethrins. 

In the search for safe insecticides the authors have prepared hundreds of new products and subjected them to preliminary screening tests against insects. That part of their work dealing with methylenedioxyphenyl derivatives was prompted by the original fundamental studies of 0. F. Hedenburg, with whom they have collaborated in this field. Two materials of this type—piperonyl butoxide (I) and piperonyl cyclonene (II)—have recently been introduced commercially. These products have definite insecticidal properties in themselves, but show their maximum efficiency toward insects and other arthropods when used in combination with pyrethrins. Furthermore, they are at least as nontoxic... 

In continuing efforts toward the development of other nontoxic insecticides, many new products are being synthesized and tested. The direction of the synthetic work is guided by the theory that the insecticidal activity of a given substance is due to the combined influence of a toxic nucleus and modifying auxiliary groups. To illustrate the theory, this paper presents information on six materials related to piperonyl butoxide, when tested in combination with pyrethrins. 

Propylpiperonyl) (butyl) diethylene glycol ether (I) (piperonyl butoxide) Modification of auxotoxic group 74 69 98 74... 

A striking illustration of the effect of chemical structure on insecticidal properties is provided by the data given in this paper on compounds related to piperonyl butoxide. According to the above theory, the methylenedioxyphenyl nucleus present in this substance is the toxophore. The materials selected for comparison show the reduction in toxicity produced, first, by modifying the toxophore, and, second, by substituting different groups for the auxotox radical. 

Of the three piperonyl compounds that have received considerable commercial attention as insecticides, a method of analysis is available only for piperonyl butoxide (41). This product gives a blue color on treatment with a reagent comprising tannic acid in a mixture of phosphoric and acetic acids. Satisfactory results can be obtained in the presence of small amounts of pyrethrins, but larger amounts tend to obscure the color. A modification of the method (21) which overcomes this difficulty is the removal of the pyrethrins by saponification with alcoholic sodium hydroxide prior to carrying out the test. 

The total-release foggers (6 oz) contained chlorpyrifos (1.000%), piperonyl butoxide (0.100%), pyrethrins (0.050%), N-octyl bicycloheptene dicarboxim-ide (0.166%), and inert ingredients, including petroleum distillates (KRID , K-Mart Corp. Troy, MI). The aerosol cans were weighed before and after use to measure discharge. 

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