61914-47-4Relevant articles and documents
Synthesis of new chiral and nonchiral pyrido [3,2-e],[1,3,4] oxadiazine derivatives
Shet,Shelar,Manvi
body text, p. 149 - 156 (2011/01/03)
A chiral series of 6,7-dichloro-3-[3-(2,2-dihalovinyl)-2,2-dimethylcyclopropyl] -1H-pyrido [3,2-e],[1,3,4] oxadiazines (a-f) and a nonchiral series of 3-substituted, 6,7-dichloro-1H-pyrido [3,2-e][1,3,4] oxadiazines (a-g) have been synthesized. The synthesized compounds were characterized by IR, 1H-NR, HPLC and mass spectral data.
Practical method for crystalline-liquid resolution of chrysanthemic acids utilizing chiral 1,1′-binaphthol monoethyl ethers directed for process chemistry
Atago, Takayuki,Tanaka, Akihiro,Kawamura, Tomoyuki,Matsuo, Noritada,Tanabe, Yoo
experimental part, p. 1015 - 1019 (2009/09/30)
We have developed an efficient practical resolution method for (1R,3R)-trans-chrysanthemic acid 1 and (1R,3S)-trans-2,2-dimethyl-3-(2,2-dichloroethenyl)cyclopropanecarboxylic acid 2, based on the preliminary results of the simpler analogues, (1R)-2,2-dichlorocyclopropanecarboxylic acid 3 and (1R)-2,2-dimethylcyclopropanecarboxylic acid 4, using a crystalline-liquid separation procedure (without column chromatography) with chiral 1,1′-binaphthol monoethyl ethers (R)-5b as the key auxiliary. Direct esterifications of 1, 2, 3, and 4 with (R)-5b gave four sets of (1R)- and (1S)-diastereomeric esters 8, 9, 6, and 7, respectively, with markedly different melting points. All of these diastereomers were easily obtained using a simple and one-step crystalline-liquid separation. The separated diastereomers 8 and 9 were easily hydrolyzed to the desired enantiopure acids 1 (>98%) and 2 (>99%), respectively, with recovery of (R)-5b (>90%).
Assignment of absolute configurations of permethrin and its synthon 3-(2,2-dichlorovinyl)-2,2-dimethylcyclopropanecarboxylic acid by electronic circular dichroism, optical rotation, and X-ray crystallography
Bicker, Wolfgang,Kacprzak, Karol,Kwit, Marcin,Laemmerhofer, Michael,Gawronski, Jacek,Lindner, Wolfgang
experimental part, p. 1027 - 1035 (2009/10/10)
The availability of single stereoisomers of biologically/toxicologically relevant chiral compounds such as the pyrethroid-type insecticide permethrin (PM) and the reliable determination of their absolute configurations are of central importance for the de
Hapten and antibody production for a sensitive immunoassay determining a human urinary metabolite of the pyrethroid insecticide permethrin
Ahn, Ki Chang,Watanabe, Takaho,Gee, Shirley J.,Hammock, Bruce D.
, p. 4583 - 4594 (2007/10/03)
Permethrin is the most popular synthetic pyrethroid insecticide in agriculture and public health. For the development of the enzyme-linked immunosorbent assay (ELISA) to evaluate human exposure to permethrin, the glycine conjugate (DCCA-glycine) of a major metabolite, cis/trans-3-(2,2- dichlorovinyl)-2,2-dimethylcyclopropane-1-carboxylic acid (DCCA), of permethrin was established as the target analyte. Four different types of the cis- and trans-isomers of immunizing haptens were synthesized as follows: N-(cis/trans-3-(2,2-dichlorovinyl)-2,2-dimethylcyclopropane-1-carbonyl)glycine (hapten 3), N-(cis/trans-3-(2,2-dichlorovinyl)-2,2-dimethylcyclopropane-1- carbonyl)-4-amino-L-phenyl-alanine (hapten 5), N-(N-(cis/trans-3-(2,2- dichlorovinyl)-2,2-dimethylcyclopropane-1-carbonyl)glycine)-amino-6-(2, 4-dinitrophenyl)aminohexanoic acid (hapten 9), and N-(cis/trans-3-(2,2- dichlorovinyl)-2,2-dimethylcyclopropane-1-carbonyl)glycine-4-oxobutanoic acid (hapten 24). Sixteen polyclonal antibodies produced against each cis- or trans-hapten-thyroglobulin conjugate as immunogens were screened against numerous hapten-bovine serum albumin conjugates as coating antigens. Six ELISAs with both a heterologous hapten structure and a heterologous hapten configuration (cis/trans or trans/cis) between antibody and coating antigen showed a high sensitivity for the target analyte. The IC50 was 1.3, 2.1, and 2.2 μg/L for the trans-target analyte and 0.4, 2.3, and 2.8 μg/L for the cis-target analyte. The immunizing haptens, except for hapten 5, provided the target specific antibodies. Molecular modeling of the haptens supported the selection of reasonable immunizing haptens that best mimicked the target analyte. Hapten 5 was suitable as a coating antigen rather than as an immunogen since it had a different geometry. Very low cross-reactivities were measured to permethrin, its free metabolite (DCCA), PBA-glycine conjugate, and glycine. The ELISA will be optimized for the detection of total cis/trans-DCCA-glycine in human urine samples.
Syntheses of 4-methoxymethylbenzyl permethrinates containing fluorine and their insecticidal activity
Zou, Xinzhuo,Qiu, Zongxing
, p. 173 - 179 (2007/10/03)
In order to investigate the relationship between the position of fluorine atom and insecticidal activity about 4-methoxymethylbenzyl permethrinates containing fluorine, 2 and 3-fluoro-4-methoxymethylbenzyl (±)-cis-permethrinate were synthesized. Their insecticidal activities were tested and the fluorine effect of title compounds was discussed.
Enzyme-linked immunosorbent assay for the pyrethroid deltamethrin
Lee, Hu-Jang,Shan, Guomin,Watanabe, Takaho,Stoutamire, Donald W.,Gee, Shirley J.,Hammock, Bruce D.
, p. 5526 - 5532 (2007/10/03)
A competitive enzyme-linked immunosorbent assay (ELISA) for the detection of deltamethrin was developed. Two haptens, cyano[3-(4-aminophenoxy)phenyl]methyl 1 R-cis-3-(2,2-dibromoethenyl)-2,2-dimethylcyclopropanecarboxylate and 3-[(±)-cyano[1R-cis-3-(2,2-dibromoethenyl)-2,2-dimethylcyclopropan ecarbonyloxy]methyl] phenoxyacetic acid, were synthesized and conjugated with thyroglobulin as immunogens. Four antisera were generated and screened against six different coating antigens. The assay that was the most sensitive for deltamethrin was optimized and characterized. The /50 for deltamethrin was 17.5 ± 3.6 μg/L, and the lower detection limit was 1.1 ± 0.5 μg/L. This ELISA assay had relatively low cross-reactivities with other major pyrethroids, such as permethrin, phenothrin, bioresmethrin, cyfluthrin, and cypermethrin. Methanol was found to be the best organic cosolvent for this ELISA, with optimal sensitivity observed at a concentration of 40% (v/v). The assay parameters were unchanged at pH values between 5.0 and 8.0, whereas higher ionic strengths strongly suppressed the absorbances. To increase the sensitivity of the overall method, a C18 sorbent-based solid-phase extraction was used for river water samples. River water samples fortified with deltamethrin were analyzed according to this method. Good recoveries and correlation with spike levels were observed.
Enzyme-Linked immunosorbent assay for the pyrethroid permethrin
Shan, Guomin,Leeman, Whitney R.,Stoutamire, Donald W.,Gee, Shirley J.,Chang, Daniel P.Y.,Hammock, Bruce D.
, p. 4032 - 4040 (2007/10/03)
Permethrin is a predominant pyrethroid widely used in agriculture and public health. A competitive enzyme-linked immunosorbent assay (ELISA) for the detection of permethrin was developed. Two haptens, the trans- and cis-isomers of 3-(4-aminophenoxy)benzyl-3-(2,2-dichloroethenyl)-2,2-dimethylcyclopropanecarb oxylate, were synthesized and conjugated with thyroglobulin as immunogens. Four antisera were generated and screened against six different coating antigens. The resulting ELISA has an I50 value of 2.50/μg/L and relatively low cross-reactivities with other major pyrethroids, such as esfenvalerate, cypermethrin, deltamethrin, and cyfluthrin. Methanol was found to be the best solvent for this ELISA, with optimal sensitivity observed at a concentration of 40% (v/v). The assay parameters are unchanged at pH values between 5.0 and 8.0, whereas higher ionic strengths (>0.2 M PBS) strongly suppress the absorbances. River water samples fortified with permethrin were analyzed according to this method and validated by GC-MS. Good recoveries and correlation with spike levels were observed, suggesting this immunoassay is valuable for environmental monitoring and toxicological studies at parts per trillion levels of permethrin.
A spectrophotometric assay for pyrethroid-cleaving enzymes in human serum
Butte, Werner,Kemper, Kerstin
, p. 49 - 53 (2007/10/03)
A direct continuous spectrophotometric assay to measure pyrethroid-cleaving enzymes in human serum was developed using cis- and trans-α-naphthyl-(2,2-dichlorovinyl)-2,2-dimethylcyclopropane carboxylate (cis- and trans-naphthyl-Cl2CA). These substrates show a structure very similar to the pyrethroids most often used (e.g. permethrin, cyfluthrin). The method is based on an increase in absorbance at 321 nm which occurs with the hydrolysis of the α-naphthyl esters to α-naphthol. The assay was optimised regarding type of buffer, pH and substrate concentrations, it was linear for at least 10 min at 37°C. These esterases were completely inhibited by bis-(4-nitrophenylphosphate), a specific carboxyesterase inhibitor. They displayed a great individual variability in human serum, activities were between less than 40 and 1000 U/l for cis-naphthyl-Cl2CA, between less than 40 and 2000 U/l for trans-naphthyl-Cl2CA, respectively. However, a correlation of enzyme activity to sex or age could not be observed. Furthermore, the activity of pyrethroid-cleaving esterases did not correspond to the activities of acylesterase, arylesterase, acetylcholinesterase or butyrylcholinesterase. Copyright (C) 1999 Elsevier Science Ireland Ltd.
Synthesis and Larvicidal Properties of Some Cyclopropylcarboxamides Related to cis-Permethrin
Taylor, Wesley G.,Hall, Tse Wai,Vedres, Darrell D.
, p. 1572 - 1576 (2007/10/03)
Twenty-seven carboxamide derivatives of (±)-cis-3-(2,2-dichloroethenyl)-2,2-dimethylcyclopropanecarboxylic acid (permethrin acid) have been synthesized and evaluated in the laboratory against mosquito larvae (Aedes aegypti). These cis-cyclopropylcarboxamides, with N-(substituted)phenyl, N-(substituted)phenylmethyl, N-(substituted)phenylethyl, N-phenylpropyl, and N-phenylbutyl groups, were synthesized from the acid chloride of permethrin acid and various arylamines in methylene chloride. The samples were characterized by 13C NMR spectroscopy and mass spectrometry. Secondary amides with electron-donating (e.g., methoxy) and electron-withdrawing (e.g., trifluoromethyl) substituants on the phenyl ring as well as nine tertiary amides were investigated. 3-(2,2-Dichloroethenyl)-2,2-dimethyl-N-(3-phenoxyphenyl) methylcyclopropanecarboxamide was the most active experimental compound and was 25 times less potent than (±)-cis-permethrin. Cyclopropylcarboxamides of the N-(substituted)phenyl, N-(substituted)phenylethyl, and N-phenylpropyl types were essentially inactive in the larvicidal tests.
Biological Activity of Pyrethroid Analogs in Pyrethroid-Susceptible and -Resistant Tobacco Budworms, Heliothis virescens (F.)
Shan, Guomin,Hammer, Robert P.,Ottea, James A.
, p. 4466 - 4473 (2007/10/03)
The phenoxybenzyl moiety of conventional pyrethroids is a major site of oxidative metabolism in resistant tobacco budworms, Heliothis virescens (F.). In this study, this group was replaced with known P450 monooxygenase-inhibiting or oxidatively blocked groups. A variety of isomers (1R/1S, cis/trans) of the resulting chrysanthemates were tested as insecticides or synergists against tobacco budworms that were insecticide-susceptible (LSU) or that expressed metabolic resistance to cypermethrin (Pyr-R). A number of compounds with pentafluorophenyl, methylenedioxyphenyl, and propargyloxyphenyl groups were insecticidal, and activity was dependent on both geometric and stereochemical configuration of the acid moiety. Both trans and cis isomers of 1(R)-fenfluthrin, which contains a pentafluorophenyl group, suppressed resistance to cypermethrin in Pyr-R insects, confirming that oxidative metabolism of the phenoxybenzyl moiety is a major mechanism of resistance in this strain. Of the methylenedioxyphenyl compounds, 1R, trans, and cis isomers were toxic and partially suppressed resistance in Pyr-R larvae. Similarly, both trans and cis isomers of α(S),1(R)-propargyloxyphenyl-containing compounds were insecticidal. Finally, α(R),1(R)-cis-methylenedioxyphenyl- and -propargyloxyphenyl- containing compounds were nontoxic but significantly enhanced toxicity of cypermethrin.
