Sulfometuron methyl, structure

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. 

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)... 

Sulfometuron-Methyl Figure 7.17. Structures of acid herbicides. 

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