Clobazam impurity C

Clobazam Impurity C is a chlorinated benzodiazepine derivative featuring a 1,4-benzodiazepine core substituted with a 3-chlorophenyl ring and an N-methylcarbamoyl group. The compound exhibits a unique structural divergence from the parent drug due to a methylation at the 7-position of the dihydro-1,4-benzodiazepin-2-one scaffold, resulting in altered steric and electronic properties. This impurity arises via nucleophilic substitution during synthetic pathways, leading to regioselective alkylation. It serves as a critical HPLC reference standard for quantifying process-related impurities in clobazam formulations.