Measurement of benzodiazepine receptor agonists metabolites and their concentration in urine

Abstract
The study objective was to detect and measure the ratio of metabolites of benzodiazepine receptor agonists in urine during forensic chemical and chemical and toxicological studies, as well as to characterize the main metabolites to use them to confirm the oral intake of the test substances. Data on the presence of metabolites in the urine will allow us to reliably confirm the intake of zaleplon, zopiclone, clobazam, and phenazepam and determine the routes of administration (intake) into the body of the victim. Benzodiazepine derivatives (clobazam and phenazepam) and non-benzodiazepines (zaleplon and zopiclone) have different chemical structures and similar mechanisms of action resulting in a similar clinical presentation of side effects and the need for forensic chemical study according to poisoning symptoms. Metabolites of benzodiazepine receptor agonists and their ratio in urine after oral administration were measured: zaleplon (parent compound), deethylzaleplon, 5-oxozaleplon, 5-oxodeethylzaleplon, oxozaleplon glucuronide; zopiclone (parent compound), zopiclone-N-oxide, N-desmethylzopiclone; clobazam (parent compound), N-desmethylclobazam, 4-hydroxyclobazam, hydroxydesmethylclobazam; phenazepam (parent compound) and 3-hydroxyphenazepam. It is advisable to determine zaleplon in urine by the presence of 5-oxaleplon (97% of the total amount of metabolites), zopiclone by zopiclone-N-oxide (86% in urine), clobazam by the parent compound (61% in urine), phenazepam by the parent compound (90—100% in urine).