6515-38-4Relevant articles and documents
Highly sensitive enzyme-linked lmmunosorbent assay for chlorpyrifos. Application to olive oil analysis
Brun, Eva M.,Garces-Garcia, Marta,Puchades, Rosa,Maquieira, Angel
, p. 9352 - 9380 (2005)
Highly sensitive enzyme-linked immunoassays for chlorpyrifos, one of the most applied insecticides, are presented. Several haptens were synthesized for immunoreagent production and ELISA development. The best immunoassays obtained are based on an indirect coated-plate immunoassay format. Two assays were optimized; one shows a limit of detection of 0.3 ng L-1, an I 50 of 271 ng L-1, and a dynamic range between 4 and 16 474 ng L-1. The other one has a limit of detection of 0.07 ng L -1, an I50 of 7 ng L-1, and a dynamic range between 0.4 and 302 ng L-1. The assays were used to quantify chlorpyrifos in olive oil using a simple and rapid sample extraction procedure. The good recoveries achieved in both assays (109% mean value) and the agreement with values given by the GC reference method (110% mean value) indicate their potential for either screening or laboratory quantification.
Chlorpyrifos transformation by aqueous chlorine in the presence of bromide and natural organic matter
Duirk, Stephen E.,Tarr, J. Christopher,Collette, Timothy W.
, p. 1328 - 1335 (2008)
The aqueous chlorination of chlorpyrifos (CP) was investigated in the presence of bromide and natural organic matter (NOM), which were identified as naturally occurring aqueous constituents that could affect CP transformation rates to the toxic product chlorpyrifos oxon (CPO). Bromide can be oxidized by chlorine to form hypobromous acid (HOBr), which was found to oxidize CP at a rate that was 3 orders of magnitude faster than was the case with chlorine: kHOBr,CP = 1.14 (± 0.21) × 109 M-1 h-1 and kHOCl,CP = 1.72 × 106 M -1 h-1, respectively. Similar to previous findings with the hypochlorite ion, hypobromite (OBr-) was found to accelerate the hydrolysis of CP and CPO: kOBr,CP = 965 (± 110) M-1 h-1 and kOBr,CPO = 1390 (± 160) M-1 h-1, respectively. Treated water from the Athens-Clarke County (ACC) water treatment plant in Athens, GA, was used in some of the experiments as a NOM source. A mechanistic model was used to adequately predict the loss of CP as well as the formation of CPO and the hydrolysis product 3,5,6-trichloro-2- pyridinol (TCP) in the presence of the ACC water.
Reaction of chlorpyrifos-methyl in aqueous hydrogen sulfide/bisulfide solutions
Jans, Urs,Miah, M. Hasan
, p. 1956 - 1960 (2003)
The kinetics of the reactions of chlorpyrifos-methyl, an organophosphorus insecticide, with hydrogen sulfide (H2S) and bisulfide (HS-) were determined in well-defined aqueous solutions. The resulting pseudo-first-order rate constant for chlorpyrifos-methyl with bisulfide yielded a second-order rate constant of (2.1 ± 0.3) × 10-3 M-1 s-1. The second-order rate constant for chlorpyrifos-methyl with hydrogen sulfide is significantly slower than the second-order rate constant with bisulfide. The contribution of H2S to the observed degradation rate constant of chlorpyrifos-methyl at concentrations of up to 4 mM H2S is not significant. The second-order rate constant of chlorpyrifos-methyl with H2S was too low to be measured in this study. The results indicate that HS- present at environmentally relevant concentrations may represent an important sink for phosphorothionate triesters in a coastal marine environment, while H2S reacts too slowly to be environmentally relevant (pH 6-9). Trichloropyridinol, the major product of hydrolysis of chlorpyrifos-methyl, is only a minor product of the reaction of chlorpyrifos-methyl with bisulfide; however, trichloropyridinol was found to be stable under the experimental conditions.
Use of Chloride Ion as a Catalyst for Dehydrochlorination Reactions: The Synthesis of 3,5,6-Trichloropyridin-2-ol
Pews, R. Garth,Gall, James A.
, p. 6783 - 6785 (1994)
The reaction conditions to prepare 2,2,4-trichloro-4-cyanobutanoyl chloride (3) in high yield via the CuCl addition of trichloroacetyl chloride (1) to acrylonitrile (2) are reported.A novel conversion of 3 to 3,5,6-trichloropyridin-2-ol (6) via 3,3,5,6-tetrachloro-3,4-dihydropyridin-2-one (4) under anhydrous conditions and without salt formation has been achieved in 90percent yield using chloride ion as a dehydrochlorination catalyst.
Biodegradation of chlorpyrifos and 3,5,6-trichloro-2-pyridinol by the epiphytic yeasts Rhodotorula glutinis and Rhodotorula rubra
Bempelou,Vontas,Liapis,Ziogas
, p. 1368 - 1378 (2018)
The possible involvement of the epiphytic yeasts Rhodotorula glutinis and Rhodotorula rubra in the biodegradation of the insecticide chlorpyrifos and its metabolite 3,5,6-trichloro-2-pyridinol (TCP), in pure cultures and in plant surfaces (tomato fruits) was investigated. Higher biodegradation rates were observed as the concentration of chlorpyrifos and the inoculum of the microorganisms were increased, while the yeasts proved to be more active at 25 and 15 °C. The presence of glucose in the mineral nutrient medium, as an extra source of carbon, delayed the biodegradation by Rhodotorula glutinis, while Rhodotorula rubra proved to be more active. The detection and quantification of the parent compound and TCP was successfully achieved using a LC/MS/MS chromatographic system. The in vitro enzymatic assays applied suggested that esterases may be involved in the biodegradation of chlorpyrifos, a fact that was further enhanced after the addition of the synergists triphenyl phosphate, diethyl maleate and piperonyl butoxide in the biodegradation trials. The decrease of chlorpyrifos residues on tomato fruits confirmed the corresponding on pure cultures, resulting in the suggestion that the yeasts R. glutinis and R. rubra can possibly be used successfully for the removal or detoxification of chlorpyrifos residues on tomatoes.
Half-life of chlorpyrifos oxon and other organophosphorus esters in aqueous solution
Lockridge, Oksana,Verdier, Laurent,Schopfer, Lawrence M.
, (2019)
Aqueous solutions of chlorpyrifos oxon are used to study the ability of chlorpyrifos oxon to catalyze protein crosslinking. Assays for protein crosslinking can avoid artifacts by using information on the stability of chlorpyrifos oxon in solution. We unde
Synthesis and herbicidal activities of aryloxyacetic acid derivatives as HPPD inhibitors
Huang, Hao,Liu, Jian-Min,Shu, Lei,Wang, Man-Man,Yan, Yi-Le,Zhang, Da-Yong,Zhang, Jian-Qiu
supporting information, p. 233 - 247 (2020/03/27)
A series of aryloxyacetic acid derivatives were designed and synthesized as 4-hydoxyphenylpyruvate dioxygenase (HPPD) inhibitors. Preliminary bioassay results reveal that these derivatives are promising Arabidopsis thaliana HPPD (AtHPPD) inhibitors, in particular compounds I12 (Ki = 0.011 μM) and I23 (Ki = 0.012 μM), which exhibit similar activities to that of mesotrione, a commercial HPPD herbicide (Ki = 0.013 μM). Furthermore, the newly synthesized compounds show significant greenhouse herbicidal activities against tested weeds at dosages of 150 g ai/ha. In particular, II4 exhibited high herbicidal activity for pre-emergence treatment that was slightly better than that of mesotrione. In addition, compound II4 was safe for weed control in maize fields at a rate of 150 g ai/ha, and was identified as the most potent candidate for a novel HPPD inhibitor herbicide. The compounds described herein may provide useful guidance for the design of new HPPD inhibiting herbicides and their modification.
Synthesis of Nickel(II) Complexes of Novel Naphthalimide Based Heterodipodal Schiff Base Ligands, Structure, Characterization and Application for Degradation of Pesticides
Pandiyan, Thangarasu,Raj, Pushap,Sidhu, Jagpreet Singh,Singh, Narinder
, (2020/07/15)
To degrade the highly toxic pesticide into less harmful components, we have synthesized four nickel complexes of naphthalimide based organic ligands. These complexes catalyze the hydrolysis of phosphorothioate bonds of organophosphates in an aqueous medium. The metal complexes {[Ni(L1)2]–[Ni(L4)2]} were synthesized by the electrochemical method and characterized using single-crystal X-ray crystallography and mass spectrometry. Analytical techniques revealed that complexes are mononuclear and possess octahedral geometry. The rate of degradation of chlorpyriphos and parathion methyl was evaluated using 31P NMR and LC-MS chromatogram. The by-product of chlorpyriphos upon catalytic degradation with complex was confirmed from mass spectrometry. It was found that chlorpyriphos degrade into 3,5,6-trichloropyridin-2-ol after 50 minutes of incubation with catalyst. However, parathion methyl took only 20 minutes to hydrolyze into its by-product. Moreover, the inhibition assay of acetylcholinesterase was performed for pesticides in the presence of metal complex and the interesting outcome was recorded.
Monitoring of the organophosphate pesticide chlorpyrifos in vegetable samples from local markets in Northern Thailand by developed immunoassay
Hongsibsong, Surat,Prapamontol, Tippawan,Xu, Ting,Hammock, Bruce D.,Wang, Hong,Chen, Zi-Jian,Xu, Zhen-Lin
, p. 1 - 14 (2020/07/04)
Chlorpyrifos is an organophosphate pesticide that is wildly used among farmers for crop protection. However, there are concerns regarding its contamination in the environment and food chain. In the present study, an in-house indirect competitive enzyme-linked immunosorbent assay (ic-ELISA) specific for detecting chlorpyrifos is developed and validated against gas chromatography–flame photometric detection (GC-FPD) as the conventional method. The developed ic-ELISA was used for detecting chlorpyrifos residue in vegetable samples. The developed ic-ELISA showed good sensitivity to chlorpyrifos at an IC50 of 0.80 μg/kg, with low cross-reactivity to other organophosphate pesticides. The 160 samples were collected from local markets located in the Chiang Rai, Chiang Mai, and Nan provinces in northern Thailand. The positive rate of chlorpyrifos residues in the vegetable samples was 33.8percent, with the highest levels found in cucumbers, coriander, and morning glory, at 275, 145, and 35.3 μg/kg, respectively. The highest median levels of chlorpyrifos found in the detected samples were Chinese cabbage (332 μg/kg), cucumber (146.3 μg/kg) and Chinese Kale (26.95 μg/kg). The developed ic-ELISA is suitable for the rapid quantitation of chlorpyrifos residues.
Synthesis method of tri(3,5,6-trichloropyridinyl)phosphite
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Paragraph 0008; 0039-0040, (2020/12/31)
The invention relates to a method for synthesizing tri(3,5,6-trichloropyridinyl)phosphite, which comprises the following steps of: synthesizing 2-hydroxy-3,5,6-trichloropyridine under an acidic condition by using sodium 3,5,6-trichloropyridin-2-olate as a raw material, conducting drying and dehydrating, and controlling the reaction temperature of the product, a catalyst and phosphorus trichlorideto be 70-93 DEG C on the premise of micro-negative pressure to obtain the tri(3,5,6-trichloropyridinyl)phosphite. The specific synthetic route is shown in the specification. Micro negative pressure and the catalyst are introduced in the reaction process, so that the generation of diester and other side reactions is reduced, the reaction speed is increased, the reaction time is shortened, the purity and yield of a target product are improved, meanwhile, an organic alkali or organic ammonia acid-binding agent is not used, the production cost is reduced, and three wastes are reduced.
