Synthesis of Flubromazepam Positional Isomers for Forensic Analysis

Designer benzodiazepines have recently appeared in many forensic cases as legal alternatives to federally scheduled drugs such as diazepam (Valium) and alprazolam (Xanax). Though current forensic instrumental techniques are often sufficient for identifying novel psychoactive substances, they may not readily differentiate between potential positional isomers. Additionally, characterization data for positional isomers of known designer benzodiazepines are widely nonexistent. In this study, flubromazepam, a recognized designer benzodiazepine since 2012, was targeted for synthesis and characterization due to its potential for federal scheduling and current legal status within the United States. A practical synthetic method was developed to prepare purified reference materials for each positional isomer of flubromazepam in which the positions of the bromine and fluorine substituents were varied. Possible isomers (9 of the 12) were successfully prepared and used for further analysis.