Analytical Challenges in Detecting New Psychoactive Substances in Anti‐Doping: A Proof‐of‐Concept Involving Pentedrone Metabolite

New psychoactive substances (NPS) have become increasingly prevalent worldwide, posing a growing challenge to public health, forensic science, and doping control. Their structural diversity, rapid emergence, and legal ambiguity complicate both toxicological assessment and analytical detection. Research into the metabolism of these compounds is limited by ethical constraints on administration studies, hindering the development of reference standards. This study presents a methodological approach for the identification and confirmation of 2-amino-1-phenylpentan-1-ol, a metabolite associated with several synthetic cathinones, including pentedrone, α-pyrrolidinopentiophenone (PVP), and N-ethylpentedrone (NEP). The compound was detected in a routine doping control sample using ultra-performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS). In the absence of a commercially available certified reference material (CRM) encompassing all potential isomeric forms, a custom synthesis of the target metabolite was undertaken. The synthesized CRM-enabled unambiguous confirmation of the analyte and its diastereomeric composition, demonstrating the importance of reference compound availability for the accurate interpretation of results in anti-doping analysis. This work highlights both the analytical challenges posed by NPS and the need for continued development of tailored CRMs to support doping control laboratories worldwide.