Furanyl fentanyl 3-furancarboxamide isomer-d5 (hydrochloride) is intended for use as an internal standard for the quantification of furanyl fentanyl 3-furancarboxamide isomer (Item No. 21213) by GC- or LC-MS. Furanyl fentanyl 3-furancarboxamide isomer is structurally similar to known opioids. It induces generalized responses in mice trained to discriminate oxycodone from saline.1 Furanyl fentanyl 3-furancarboxamide isomer-d5 (hydrochloride) is regulated as a Schedule I compound in the United States. This product is intended for research and forensic applications.WARNING This product is not for human or veterinary use.