0000000000312840
AUTHOR
Colin Swithenbank
Synthesis and properties of a photoaffinity labeling reagent for protoporphyrinogen oxidases, the target enzymes of diphenyl ether herbicides
A diazoketone 3 has been synthesized in two steps from acifluorfen 1, a diphenyl ether herbicide. Like the parent compound 1, the diazoketone 3 is toxic to plant cells and inhibits protoporphyrinogen oxidase, the molecular target of diphenyl ether herbicides. On photolysis of 3 in methanol, the generated carbene mainly undergoes the Wolff rearrangement to a ketene which further adds methanol, but many other products are observed. A tritiated derivative of 3 has been prepared which is suitable for photoaffinity labeling experiments.
Synthesis of tritiated derivatives of the diphenylether herbicides acifluorfen and acifluorfen methyl
Acifluorfen 1 and acifluorfen methyl 2, two herbicides of the diphenylether family, are inhibitors of protoporphyrinogen oxidases. Two tritiated derivatives of these compounds, namely 3-[3H]-5-[2-chloro-4-(trifluoromethyl)phenoxy]-2-nitrobenzoic acid [3H]-1, and methyl 3-[3H]-5-[2-chloro-4-(trifluoromethyl)phenoxy]-2-nitrobenzoic acid [3H]-2, have been synthesised from 3-[3H]-5-hydroxybenzoic acid, in order to probe their interactions with the target enzymes.