Inhibition of acetylcholinesterase by O-(methylcarbamoyl) oximes. Structure-activity relationships

Since the anticholnesterase activity and the mechanism of alcaline hydrolysis of O-(methyl-carbamoy)benzaldoximes and acetopheniximes are analogous to those of phenyl N-methylcarbamates, these two groups of derivatives were compared by means of structure activity relationships.The correlation with the electronic substituent parameter δ showed that the mechanism of inhibition of acetylcholinesterase by O-(methylcarbamoyl)oximes is the same as that observed for phenyl N-methylcarbamates bearing strongly electron-withdrawing substituents.The correlations with the bimolecular rate constant Koh suggest that the mechanism of the alkaline hydrolysis of oximes carbamates may closely parallel their mechanism of interaction with acetylcholinesterase at the seryl hydroxyl.