Technical note: Identification of the novel benzodiazepine 3-hydroxy desalkylgidazepam within PSNI tablet seizures in Northern Ireland.

Police Service of Northern Ireland (PSNI) drug seizures from 6 locations yielded 8 separate items containing tablets which on chemical analysis were found to contain the previously unreported designer benzodiazepine (DBZD) 3-hydroxy desalkylgidazepam. The tablets were similar in appearance to previously encountered illicit diazepam tablets, being either yellow or blue in colour, and marked 'MSJ'. The items were all seized from within the greater Belfast area between April and September 2025. Initial structure elucidation was by gas chromatography (GC)/nuclear magnetic resonance (NMR) and ultra high performance liquid chromatography (UPLC) coupled to high resolution mass spectrometry (HRMS) in collaboration with Queens University Belfast (QUB). These analyses were followed by confirmation at Forensic Science Northern Ireland (FSNI) employing UPLC coupled to HRMS and using a certified reference material.