For laboratory research requirements.

IUPAC: 5-nitro-2-(4-propoxybenzyl)-1-(2-(pyrrolidin-1-yl)ethyl)-1H-benzo[d]imidazole.

Protonitazepyne (N-pyrrolidino protonitazene) is a benzimidazole derivative with opioid effects, which has been sold as a designer drug over the internet, first being mentioned in mid 2022 and definitively identified in drug seizures in Canada in early 2023 and Ireland in late 2023. It is an analogue of etonitazene where the ethoxy group has been extended to propoxy, and the N,N-diethyl substitution has been cyclised into a pyrrolidine ring. While formal studies into its pharmacology have yet to be carried out, it is believed to be slightly less potent than the ethoxy analogue etonitazepyne but still a potent opioid.