The in vitro hepatic microsomal metabolism of methyl 2-(2(3H)- benzoxazolone-3-yl)acetate in rats

Abstract

The in vitro hepatic microsomal metabolism of methyl 2-(2(3H)- benzoxazolone-3-yl)acetate (I) was studied using hepatic washed rat microsomal preparations fortified with NADPH. The substrate (I) and its potential hydrolytic metabolite 2-(2(3H)-benzoxazolone-3-yl)acetic acid (II) and 2(3H)-benzoxazolone (III), a potential dealkylation metabolite, were separated using a reverse phase HPLC system which consisted of a C18 column and a mobile phase of acetonitrile: 0.02 M phosphate buffer (30:70, final pH 7) at a flow rate of 1 ml/min with UV detection at 254 nm. The substrate (I) was incubated with rat microsomal preparations, extracted into DCM, and finally evaporated under nitrogen. The results from HPLC studies showed that (I) was metabolised to (II) and (III) by rat microsomes in the presence of NADPH.