59042-49-8Relevant articles and documents
Stereoselective Synthesis of cis-3-(2,2-Dichlorovinyl)-2,2-dimethylcyclopropanecarboxylic Acid
Kleschick, William A.
, p. 5429 - 5433 (1986)
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Purification and characterization of a novel pyrethroid hydrolase from Aspergillus niger ZD11
Liang, Wei Q.,Wang, Zhuo Y.,Li, He,Wu, Pei C.,Hu, Ji M.,Luo, Na,Cao, Li X.,Liu, Yu H.
, p. 7415 - 7420 (2007/10/03)
The pyrethroid pesticides residues on foods and environmental contamination are a public safety concern. Pretreatment with pyrethroid hydrolase has the potential to alleviate the conditions. For this purpose, a fungus capable of using pyrethroid pesticides as a sole carbon source was isolated from the soil and characterized as Aspergillus niger ZD11. A novel pyrethroid hydrolase from cell extract was purified 41.5-fold to apparent homogeneity with 12.6% overall recovery. It is a monomeric structure with a molecular mass of 56 kDa, a pl of 5.4, and the enzyme activity was optimal at 45°C and pH 6.5. The activities were strongly inhibited by Hg2+, Ag+, and p-chloromercuribenzoate, whereas less pronounced effects (5-10% inhibition) were observed in the presence of the remaining divalent cations, the chelating agent EDTA and phenanthroline. The purified enzyme hydrolyzed various insecticides with similar carboxylester. trans-Permethrin is the preferred substrate.
Thermal decomposition and isomerization of cis-permethrin and β-cypermethrin in the solid phase
Audino, Paola Gonzalez,Licastro, Susana A.,Zerba, Eduardo
, p. 183 - 189 (2007/10/03)
The stability to heat of cis-permethrin and β-cypermethrin in the solid phase was studied and the decomposition products identified. Samples heated at 210°C in an oven in the dark showed that, in the absence of potassium chlorate (the salt present in smoke-generating formulations of these pyrethroids), cis-permethrin was not isomerized, although in the presence of that salt, decomposition was greater and thermal isomerization occured. Other salts of the type KXO3 or NaXO3, with X being halogen or nitrogen, also led to a considerable thermal isomerization. Heating the insecticides in solution in the presence of potassium chlorate did not produce isomerization in any of the solvents assayed. Salt-catalysed thermal cis-trans isomerization was also found for other pyrethroids derived from permethrinic or deltamethrinic acid but not for those derived from chrysanthemic acid. The main thermal degradation processes of cis-permethrin and β-cypermethrin decomposition when potassium chlorate was present were cyclopropane isomerization, ester cleavage and subsequent oxidation of the resulting products. Permethrinic acid, 3-phenoxybenzyl chloride, alcohol, aldehyde and acid were identified in both cases, as well as 3-phenoxybenzyl cyanide from β-cypermethrin. A similar decomposition pattern occurred after combustion of pyrethroid fumigant formulations.
