Some observations on the chemical and stereochemical specificity of the de-alkylation of organophosphorus esters by a hepatic glutathione transferase.

Hepatic glutathione (GSH) S-methyl transferase from rabbit, pig and dog demethylates dimethyl phosphate triesters. No stereospecificity towards racemic ethyl methyl 2-chloro-1-(2,4-dichlorophenyl)vinyl phosphate could be demonstrated but the enzyme exhibited some selectivity towards the (+) and (-) forms of O-methyl S-methyl 1-naphthyl phosphorothiolate. Pig liver enzyme, purified 30-fold, demethylated th prochiral substrate dimethyl 1-naphthyl phosphorothionate with 90% stero-selectivity.