Chloroacetamide herbicide

Much of the chloroacetyl chloride produced is used captively as a reactive intermediate. It is useful in many acylation reactions and in the production of adrenalin [51-43-4] diazepam [439-15-5] chloroacetophenone [532-27-4] chloroacetate esters, and chloroacetic anhydride [541-88-8]. A major use is in the production of chloroacetamide herbicides (3) such as alachlor [15972-60-8]. 

Stable to acid and base in the pH range 3-8. Thenylchlor is a chloroacetamide herbicide for the preemergence and post-planting control of annual grass and broad-leaved weeds in paddy rice The residue definition is for the parent, thenylchlor, only... 

Measurement of Chloroacetanilide and Chloroacetamide Herbicide Degradates in Drinking Water by SPE and... 

SPE LC/MS/MS methods have been developed for the determination of polar pesticides (as propanyl, thiobencarb, diuron, simazine, bentazone etc.) and of their degradation products in waters with LOQ aronnd 25 ng L (Figure 18.1) [73], for the determination of chloroacetamide herbicides (LOD=25ng L ) [74], of sulfonylureas, bentazone, and phenoxyacids in river and drainage waters (LOD of the order of few ng L" ) [9]. 

J.D. Vargo, Determination of chloroacetanilide and chloroacetamide herbicides and their polar degradation products in water by LC/MS/MS. In Liquid Chromatography/Mass Spectrometry, MS/MS and Time of Flight MS Analysis of Emerging Contaminants, I. Ferrer, E.M. Thurman (Eds.), American Chemical Society, Washington, DC, 2003. 

Frank, R., B.S. Clegg, C. Sherman, and N.D. Chapman (1990b). Triazine and chloroacetamide herbicides in Sydenham River water and municipal drinking water, Dresden, Ontario, Canada, 1981-1987. Arch. Environ. Contam. Toxicol., 19 319-324. 

Carlson D. L. (2003) Environmental transformations of chloroacetamide herbicides hydrolysis and reaction with iron pyrite. PhD Dissertation, Johns Hopkins University, Baltimore, MD. 

Carlson D. L. and Roberts A. L. (2002) Acid-and base-catalyzed hydrolysis of chloroacetamide herbicides. Amer. Chem. Soc., Div. Environ. Chem., Nat. Meeting, Symposium on Chemistry of EPA Contaminant Candidate List Compotmds, presented August, 2002, Boston, MA. 

J.D. Vargo, Determination of sulfonic acid degradates of chloroacetanilide and chloroacetamide herbicides in groundwater by LC-MS-MS, Anal. Chem., 70 (1998) 2699. 

The chlorine atom of a-chloroacetamide herbicides is activated by the adjacent carbonyl group, so chlorine easily reacts with nucleophiles, and hence with thiol groups. The covalent bonds formed result in inhibition of protein synthesis and wilting of the plant (Jaworski, 1969). 

Hladik ML, Hsiao JJ, Roberts AL (2005) Are neutral chloroacetamide herbicide degra-dates of potential environmental concern Analysis and occurrence in the upper Chesapeake Bay. Environ Sci Technol 39 6561-6574... 

Hladik ML, Bonwer EJ, Roberts AL (2008) Nentral chloroacetamide herbicide degradates and related componnds in Midwestern United States drinking water sonrces. Sci Total Environ 390 155-165... 

Hladik ML, Roberts AL, Bouwer ES (2006) Chloroacetamide Herbicides and Their Transformation Products in Drinking Water. Report No. 91123. Awwa Research Foundation, Denver... 

Phytotoxic diloroacetamides provided a linear relationship between severe inhibition of growth and inhibition of the incorporation of [ CJoleic acid into VLCFAs in Scenedesmus acutus [7]. In higher plants, the incorporation of [ C] stearic acid or malonyl-CoA into VLCFAs was inhibited by diloroacetamides while the formation of fatty acids up to Cig was not influenced [8]. Acyl elongation with 20 0-CoA and 18 0-CoA primer substrates was inhibited by the active (S)-enantiomer of metolachlor but not by the (R)-isomer [1, 9). Inhibition of VLCFA formation was also observed in metazachlor-resistance mutant (Mz-1) cells of S. acutus [9]. Thus, the phytotoxic action of chloroacetamide herbicides is most likely by the inhibition of VLCFA synthesis. 

Safener-enhanced Glutathione Conjugation Prevents Chloroacetamide Herbicide Effects on Plant Cell Membranes... 

Figure 2. Chloroacetamide herbicides - possible group specific reagents.

INFLUENCE OF CHLOROACETAMIDE HERBICIDES ON SCENEDESMUS ACVTUS FATTY ACIDS. A CENTRAL ROLE OF OLEIC ACID ... 

Couderchet M, Brozio B, Boger P. Effect and metabolism of the chloroacetamide herbicide metazachlor comparison of plant cell suspension cultures and seedlings. J Pestic Sci 1994 19 127-135. 

Chloroacetamide herbicides are applied for the control of preemergence grass and some broadleaf weeds. Their mode of action, however, is not understood. It has been reported that lipid synthesis is one of the target sites although such an effect is not seen with all tissues inhibition of cuticular wax formation has also been found. ... 

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