Specific binding of racemic oxazepam esters to rat brain synaptosomes and the influence of bioactivation by esterases.

Six aliphatic esters of oxazepam were investigated for 3H-diazepam displacing activity and hydrolysis in rat in the brain P2-fraction treated with diisopropylfluorophosphate. The esters are prodrugs in relation to oxazepam. Increasing size of the 3-substituent and steric hindrance increased the value of IC50. Controversial reports on oxazepam hemisuccinate could be explained by its stereoselective hydrolysis in vivo.