FDU-NNE1 (also known as FDU-NNEI and FDU-MN-24) is an indole-based synthetic cannabinoid that is presumed to be a potent agonist of the CB<sub>1</sub> receptor and has been sold online as a designer drug. Given the known metabolic liberation (and presence as an impurity) of amantadine in the related compound APINACA, it is suspected that metabolic hydrolysis of the amide group of FDU-NNE1 will release 1-naphthylamine, a known carcinogen.