Hydroxy atrazine

Foster, T.S. and S.U. Khan. 1976. Metabolism of atrazine by the chicken. Jour. Agric. Food Chem. 24 566-570. Foster, T.S., S.U. Khan, and M.H. Akhtar. 1980. Metabolism of deethylatrazine, deisopropylatrazine, and hydroxy atrazine by the soluble fraction (105000 g) from goose liver homogenates. Jour. Agric. Food Chem. 28 1083-1085. 

Shimabukuro et al. (1966) identified 2-chloro-4-amino-6-isopropylamino-i-triazine (G-30033) as a major metabolite in shoots of mature pea plants. These results indicated that a second mechanism for tolerance to atrazine existed in some moderately susceptible plants. Later, Shimabukuro (1967a) was able to demonstrate that atrazine could be metabolized independently in both roots and shoots of young pea plants to 2-chloro-4-amino-6-isopropylamino-.t-triazine. This metabolite was much less phytotoxic than the parent compound. The metabolism of atrazine in resistant com and sorghum, in intermediately susceptible pea, and in highly susceptible wheat was reported by Shimabukuro (1967b). This study revealed two possible pathways for metabolism of atrazine in higher plants. All species studied were able to metabolize atrazine by TV-deal kyI ation of either of the two alkyl groups present. Com and wheat that contain the cyclic hydroxyamate (2,4-dihydroxy-7-methoxy-l,4-benzoxazine-3-one) also metabolized atrazine by conversion to hydroxy-atrazine (G-34048). Subsequent metabolism was postulated to be by conversion to more polar compounds. 

It is common for the metabolite of the pesticide to be found more frequently than the pesticide itself.66 The level of atrazine in groundwater was half that of its metabolites. Metabolites found in a stream included hydroxy atrazine, deethylhydroxyatrazine, and deisopropylhydroxyatrazine... 

Due to lack of adequate TLC visualization, secondary confirmation of some metabolites by TLC comparison with synthetic reference standards was not possible. Chemical conversion of a number of thiomethyl triazines to their respective hydroxy-derivatives was carried out in order to obtain more easily visualized products. After 6 N HCl hydrolysis, ametryn was converted exclusively to 6-hydroxy-atrazine (CG-7). 

LEE of relatively polar and water-soluble organic compounds is, in general, difficult. The recovery obtained from 1 L of water with dichloromethane is 90% for Atr azine, but lower for its more polar, degradation products, such as de-iso-propyl- (16%) de-ethyl (46%) and hydroxy-atrazine (46%). By carrying out LEE with a mixture of dichloromethane and ethyl acetate with 0.2 M anunonium formate, the extraction recoveries for the three degradation products were increased to 62,87, and 65%,respectively [1]. 

Milk Isotachophoresis Conductivity 2ng 40% methanol, 10 mM sodium acetate pH 4.8, 0.2% hydroxy-ceUulose (leading electrolyte), 40% methanol, 20 mM acetic acid (terminating electrolyte) Prometryne, desmetryne, terbutryne, atrazine (OH metabolites), simazine (OH metabolites) 126... 

Amino-4-chloro-6-hydroxy-s-triazine, see Atrazine 2-Amino-4-chlorophenol, see Chlorpropham. 

Amino-4-hydroxy-6-chloro-s-triazine, see Atrazine 4-Amino-3-hydroxy-5,6-dichloropicolinic acid, see... 

Diamino-6-hydroxy-lV-ethyl-lV-(l-methylethyl)-s-triazine, see Atrazine... 

Li and Felbeck (1972) reported that the half-lives for atrazine at 25 °C and pH 4 with and without fulvic acid (2%) were 1.73 and 244 d, respectively. The hydrolysis half-lives in a 5 mg/L fulvic acid solution and 25 °C at pH values of 2.9, 4.5, 6.0, and 7.0 were 34.8, 174, 398, and 742 d, respectively. The only product identified was 2-(ethylamino)-4-hydroxy-6-isopropylamino-5-triazine (Khan, 1978). The primary degradative pathway appears to be chemical (i.e., hydrolysis) rather than microbial (Armstrong et al., 1967 Best and Weber, 1974 Gormley and Spalding, 1979 Geller, 1980 Lowder and Weber, 1982 Skipper et al, 1967). 

Pelizzetti et al. (1990) investigated the photocatalytic degradation of atrazine in solution in the presence of suspended titanium dioxide as a catalyst under simulated sunlight. Degradation was rapid but mineralization did not occur. Intermediate compounds included 6-hydroxy-A/-ethyl-/V -(l-methylethyl)-5 triazine-2,4-diamine, 2,4-diamino-6-chloro-A/-(l-methylethyl)-5-triazine, 2,4-di-amino-6-chloro-/V-ethyl-5-triazine, 2,4-diamino-6-chloro-5-triazine, 2,4-diamino-6-hydroxy-5-tri-azine, 2-amino-4,6-dihydroxy-5-triazine, 2-amino-4-hydroxy-6-chloro-5-triazine, 2,4-dihydroxy-6-chloro-s-triazine, 6-chloro-/V-acetyl-/V -(l-methylethyl)-5-triazine-2,4-diamine, and cyanuric acid as the final product. 

Chemical/Physical. The hydrolysis half-lives of atrazine in aqueous buffered solutions at 25 °C and pH values of 1, 2, 3, 4, 11, 12 and 13 were reported to be 3.3, 14, 58, 240, 100, 12.5, and 1.5 d, respectively (Armstrong et al., 1967). Atrazine does not hydrolyze in uncatalyzed solutions, even under elevated temperatures. The estimated half-life of atrazine in neutral, uncatalyzed water at pH 6.97 and 25 °C is 1,800 yr. Under acidic conditions, hydrolysis proceeds via mono- and diprotonated forms (Plust et al., 1981). Atrazine is stable in slightly acidic or basic media, but is hydrolyzed to hydroxy derivatives by alkalies and strong mineral acids (Windholz et al., 1983). Atrazine reacts with strong mineral acids forming hydroxyatrazine (Montgomery and Freed, 1964). 

In the presence of hydroxy or perhydroxy radicals generated from Fenton s reagent, atrazine undergoes oxidative dealkylation in aqueous solutions (Kaufman and Kearney, 1970). Major products identified by GC/MS included deisopropylatrazine (2-chloro-4-ethylamino-6-amino-s-triazine), 2-chloro-4-amino-6-isopropylamino-5-triazine, and a dealkylated dealkylatrazine (2-chloro-4,6-diamino-s-triazine) (Kaufman and Kearney, 1970). 

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