Sulfometuron-methyl

Sulfometuron methyl Sulphur dioxide Sulphur hexafluoride Sulphuric acid -... 

The sulfonyl urea sulfometuron methyl is stable at neutral or alkaline pH values, but is hydrolyzed at pH 5 to methyl 2-aminosulfonylbenzoate that is cyclized to saccharin (Figure 1.21) (Harvey et al. 1985). The original compound is completely degraded to CO2 by photolysis. 

M. K. Koeppe, C. F. Mucha, Metabobsm of Sulfometuron Methyl in Lactating Goats , J. Agric. Food. Chem. 1991, 39, 2304-2309. 

Soil. In unsterilized soils, 58% of C-labeled sulfometuron-methyl degraded after 24 wk. Metabolites identified were 2,3-dihydro-3-oxobenzisosulfonazole (saccharin), methyl-2-(amino-sulfonyl) benzoate, 2-aminosulfonyl benzoic acid, 2-(((aminocarbonyl)amino)sulfonyl) benzoate, and [ C]carbon dioxide. The rate of degradation in aerobic soils was primarily dependent upon pH and soil type (Anderson and Dulka, 1985). The reported half-life in soil was approximately 4 wk (Hartley and Kidd, 1987). 

Chemical/Physical Sulfometuron-methyl is stable in water at pH values of 7 to 9 but is rapidly hydrolyzed at pH 5.0 forming methyl-2-(aminosulfonyl) benzoate and saccharin. When sulfometuron-methyl in an aqueous solution was exposed to UV light (k = 300-400 nm), it degraded to the intermediate methyl benzoate which then mineralized to carbon dioxide (Harvey et ah, 1985). 

Anderson, J.J. and Dulka, J.J. Environmental fate of sulfometuron methyl in aerobic soils, J. Asric. Food Chem., 33(41 596-602, 1985. 

Both chlorsulfuron and sulfometuron methyl can be prepared by the reaction of the appropriate arylsulfonyl isocyanate and the substituted heterocyclic amine as shown in Fig. 2. 

There are several commercially available sulfonylurea herbicides that contain a 2-pyrimidine group <2006H(68)561>. These compounds, which function by inhibition of acetolactate synthase (ALS), an enzyme involved in the early stage of branched-chain amino acid synthesis, include sulfometuron-methyl 1095, primisulfuron-methyl 1096, chlorimuron-ethyl 1097, bensulfuron-methyl 1098, ethoxysulfuron 1099, nicosulfuron 1100, and pyrazosulfuron-ethyl 1101. Related nonsulfonylureas include the sulfide pyrftalid 1102 and the ether pyriminobac-methyl 1103. 

Sulfite reductase(s) 794, 861, 861s Sulfoquinovose 165s Sulfogalactosylglycerolipid 387s Sulfometuron methyl 735s Sulfonamides 473, 473s Sulfonolipids 388 Sulfonylureas 421 receptor 421... 

Ahrens, J.F. (1985). Evaluation of sulfometuron methyl for weed control in Christmas tree plantings. Proc. Northeast. Weed Sci. Soc., 39 249-253. 

Hubbard, R.K., R.G. Williams, M.D. Erdman, and L.R. Marti (1989). Chemical transport from coastal plain soils under simulated rainfall II. movement of cyanazine, sulfometuron-methyl, and bromide. Trans Am. Soc. Agric. Eng., 32 1250-1257. 

Wauchope, R.D., R.G. Williams, and L.R. Marti (1990). Runoff of sulfometuron-methyl and cyanazine from small plots Effects of formulation and grass cover. J. Environ. Qual., 19 119-125. 

CISHUO trans-1-methoxy-4-(2-phenylvinyl)benzene 1694-19-5 21.33 1.1133 2 28428 C15H16N405S sulfometuron methyl 74222-97-2 25.00 1.4008 2... 

S5mthase is not present in mammals it is a popular target for herbicides. It is inhibited by many of the most widely used herbicides including sulfometuron methyl, whose structure is shown here. 

Sulfonylureas form a group of selective herbicides. The general structure is given below in Table 7.4. Rj and Rj generally are substituted heterocyclic rings, e.g., 4,6-dimethylpyrimidin-2-yl and 2-(benzoic acid methyl ester) for sulfometuron methyl and 4-methoxy-6-methyl-l,3,5-triazin-2-yl and l-(2-chlorophenyl) for chlorsulfuron, respectively. The compoimds are thermally labile and cannot readily be derivatized and are therefore not amenable to GC-MS. 

Product-ion MS-MS mass spectra of sulfonylureas, based on a protonated molecule generated by ESI, were reported by Li et al. [53], For most compounds, only two or three prodnct ions were detected, e.g., m/z 141 and 167 for chlorsulfuron, and m/z 150 and 199 for sulfometuron methyl. The [R,N=C=0+H]" fragment is a common fragment in MS-MS. Negative-ion MS-MS mass spectra of chlorsulfuron, metsnUuron-methyl, thifensulfuron-methyl, and tribenuron-methyl were tabulated [43, 52]... 

General LC/MS Conditions for Sulfonylurea Multiresidue Analysis. We have developed general thermospray LC/MS conditions for the purpose of separating and detecting six different sulfonylurea herbicides. These conditions can be used as a guide fra- a variety of LC/MS residue applications which may require the analysis of one or more of these herbicides. Our procedure includes GLEAN (chlorsulfuron), ALLY (metsulfuron methyl), HARMONY (thiameturon) and EXPRESS cereal herbicides, CLASSIC (chlorimuron ethyl) soybean herbicide and OUST (sulfometuron-methyl) noncrop land herbicide. (Structure 1)... 

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