This paper reports on the identification and full chemical characterization of the substance colloquially called “etonitazepyne” or “ N ‐pyrrolidino etonitazene” (2‐(4‐ethoxybenzyl)‐5‐nitro‐1‐(2‐(pyrrolidin‐1‐yl)ethyl)‐1 H ‐benzo[ d ]imidazole), a potent NPS opioid of the 5‐nitrobenzimidazole cla…