Metabolic N-oxidation of metronidazole

Abstract

Abstract Metronidazole when treated at the N-3 nitrogen with a mixture of hydrogen peroxide and acetic acid, or liver homogenate preparations, yields the N-3 oxide as identified by thin-layer chromatographic analysis on silica gel G, RF 0ṁ62 in ethanol-chloroform-ammonia (50:49:1), by chemical reduction with sulphur dioxide, and by ultra-violet spectrophotometry and nuclear magnetic resonance spectroscopy. Incubation of metronidazole at 37°C with rat liver 10 000g supernatant fortified with cofactors gave a product with identical chromatographic and UV spectral data suggesting that metronidazole like other tertiary amine drugs undergoes microsomal N-oxidation.