Abstract
Objective: The aim of this study was to examine the metabolism of donepezil via N
– oxidation of donepezil HCl in vitro, and the kinetic studies at a temperature similar
to that of the human body.
Methods: Direct reaction of donepezil with hydrogen peroxide and formic acid at
room temperature, the N – oxide undergoes a series of rearrangements, the reaction
was followed by ultraviolet at λmax= 268 nm at 37 °C. The donepezil N- oxide was
also tested as potential cholinesterase inhibitor using electrometric for cholinesterase
determination.
Results: According to the present work , the structure of donepzil N- oxide was
elucidated using spectroscopic analysis , also , in vitro kinetic study at 37 °C using
ultraviolet spectrophotometer at λmax = 268 nm showed that the reaction proceeded at
a first order reaction . Biologically, the compound was found to inhibit both plasma
and erythrocyte cholinesterase activities in vitro ..
Conclusion: We concluded that the N- oxide of denepezil undergoes a series of
rearrangements, the reaction followed first order at 37 °C. It has a potential
anticholinesterase activity
