dextromethorphan and azobis(isobutyronitrile)

In the study of the degradation of drug substances by molecular oxygen, their specific reaction mechanisms must be taken into account. The rate-determining step is usually the reaction of the substrate with a radical chain initiator, which is often an unknown impurity. The reactivity and selectivity of autoxidation can be controlled better by using a radical chain initiator, such as AIBN, than by changing the temperature or the oxygen pressure. In this paper the products profiles of four pharmaceutical substances in a simple oxidation test with AIBN are compared with the results of long term natural stability tests or with already established stabilities.

Topics: Anti-Anxiety Agents; Benzodiazepines; Benzodiazepinones; Chromatography, High Pressure Liquid; Dextromethorphan; Drug Contamination; Nitriles; Oxidation-Reduction; Phenylbutazone; Trifluoperazine