Reactions of N-acetoxyphenacetin: an in vitro model for the metabolism of phenacetin

Abstract

The solvolysis reactions of N-acetoxy-4'-ethoxyacetanilide in the presence of nucleophiles under neutral conditions and at low pH yield p-benzoquinone, 3'-substituted 4'-hydroxyacetanilides and 2'-substituted 4'-ethoxyacetanilides. The product ratio is dependent on the nature of the nucleophile and the pH. This type of reaction accounts for many of the minor metabolites of phenacetin.