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Resmethrin
Resmethrin is a pyrethroid insecticide with many uses, including control of the adult mosquito Mosquitoes (or mosquitos) are members of a group of almost 3,600 species of small flies within the family Culicidae (from the Latin ''culex'' meaning " gnat"). The word "mosquito" (formed by ''mosca'' and diminutive ''-ito'') is Spanish for "li ... population. The resmethrin molecule has four stereoisomers determined by cis-trans orientation around a carbon triangle and chirality. Technical resmethrin is a mixture of (1R,trans)-, (1R,cis)-, (1S,trans)-, and (1S,cis)- isomers, typically in a ratio of 4:1:4:1. The 1R isomers (both trans and cis) show strong insecticidal activity, while the 1S isomers do not. The (1R,trans)- isomer is also known as bioresmethrin,(+)-trans-resmethrin, or d-trans-resmethrin; although bioresmethrin has been used alone as a pesticide active ingredient, it is not now registered as a separate active ingredient (AI) by the U.S. EPA. The (1R,cis)- isomer ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pyrethroid
A pyrethroid is an organic compound similar to the natural pyrethrins, which are produced by the flowers of pyrethrums (''Chrysanthemum cinerariaefolium'' and ''Chrysanthemum coccineum, C. coccineum''). Pyrethroids are used as commercial and household insecticides. In household concentrations pyrethroids are generally harmless to humans. However, pyrethroids are toxic to insects such as bees, dragonflies, mayflies, Horse-fly, gadflies, and some other invertebrates, including those that constitute the base of aquatic and terrestrial food webs. Pyrethroids are toxic to aquatic organisms, especially fish.Pyrethroids fact sheet from the Illinois Department of Public Health. They have been shown to be an effective control measure for malaria outbreaks, through indoor applications. ...
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Insecticide
Insecticides are substances used to kill insects. They include ovicides and larvicides used against insect eggs and larvae, respectively. Insecticides are used in agriculture, medicine, industry and by consumers. Insecticides are claimed to be a major factor behind the increase in the 20th-century's agricultural productivity. Nearly all insecticides have the potential to significantly alter ecosystems; many are toxic to humans and/or animals; some become concentrated as they spread along the food chain. Insecticides can be classified into two major groups: systemic insecticides, which have residual or long term activity; and contact insecticides, which have no residual activity. The mode of action describes how the pesticide kills or inactivates a pest. It provides another way of classifying insecticides. Mode of action can be important in understanding whether an insecticide will be toxic to unrelated species, such as fish, birds and mammals. Insecticides may be repellent ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mosquito
Mosquitoes (or mosquitos) are members of a group of almost 3,600 species of small flies within the family Culicidae (from the Latin ''culex'' meaning " gnat"). The word "mosquito" (formed by ''mosca'' and diminutive ''-ito'') is Spanish for "little fly". Mosquitoes have a slender segmented body, one pair of wings, one pair of halteres, three pairs of long hair-like legs, and elongated mouthparts. The mosquito life cycle consists of egg, larva, pupa, and adult stages. Eggs are laid on the water surface; they hatch into motile larvae that feed on aquatic algae and organic material. These larvae are important food sources for many freshwater animals, such as dragonfly nymphs, many fish, and some birds such as ducks. The adult females of most species have tube-like mouthparts (called a proboscis) that can pierce the skin of a host and feed on blood, which contains protein and iron needed to produce eggs. Thousands of mosquito species feed on the blood of various hosts ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Furans
Furan is a heterocyclic organic compound, consisting of a five-membered aromatic ring with four carbon atoms and one oxygen atom. Chemical compounds containing such rings are also referred to as furans. Furan is a colorless, flammable, highly volatile liquid with a boiling point close to room temperature. It is soluble in common organic solvents, including alcohol, ether, and acetone, and is slightly soluble in water. Its odor is "strong, ethereal; chloroform-like". It is toxic and may be carcinogenic in humans. Furan is used as a starting point for other speciality chemicals. History The name "furan" comes from the Latin ''furfur'', which means bran. ( Furfural is produced from bran.) The first furan derivative to be described was 2-furoic acid, by Carl Wilhelm Scheele in 1780. Another important derivative, furfural, was reported by Johann Wolfgang Döbereiner in 1831 and characterised nine years later by John Stenhouse. Furan itself was first prepared by Heinrich ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Benzyl Compounds
In organic chemistry, benzyl is the substituent or molecular fragment possessing the structure . Benzyl features a benzene ring () attached to a methylene group () group. Nomenclature In IUPAC nomenclature, the prefix benzyl refers to a substituent, for example benzyl chloride or benzyl benzoate. Benzyl is not to be confused with phenyl with the formula . The term benzylic is used to describe the position of the first carbon bonded to a benzene or other aromatic ring. For example, is referred to as a "benzylic" carbocation. The benzyl free radical has the formula . The benzyl cation or phenylcarbenium ion is the carbocation with formula ; the benzyl anion or phenylmethanide ion is the carbanion with the formula . None of these species can be formed in significant amounts in the solution phase under normal conditions, but they are useful referents for discussion of reaction mechanisms and may exist as reactive intermediates. Abbreviations The abbreviation "Bn" denotes benzyl. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
