Biooxidation of methyl group: application to the preparation of alcohol and acid metabolites of terfenadine, ebastine and analogues

The aim of this study was to found the best conditions to prepare metabolites of terfenadine, ebastine and analogues. For that purpose we investigated the structural substrate requirements needed for the oxidative whole cell activity and selected the most efficient conditions to obtain each compound. Our results showed that either alcohol or acid derivative arising from the oxidation of a methyl group is the main product, ratio depending on the microorganism used and on the culture conditions of cells. The oxidized metabolites were synthesized at preparative scale and isolated in 35–88% yield before characterization.