Cannabipiperidiethanone, (CPE, or 1-(N-methylpiperidin-2-ylmethyl)-3-(2-methoxyphenylacetyl)indole), is a synthetic cannabinoid that has been found as an ingredient of "herbal" synthetic cannabis blends sold in Japan, alongside JWH-122 and JWH-081. Its binding affinity was measured at the CB1 and CB2 receptors and it was found to have an IC50 of 591nM at CB1 and 968nM at CB2, making it 2.3x and 9.4x weaker than JWH-250 at these two targets respectively.
^Uchiyama N, Kikura-Hanajiri R, Goda Y (2011). "Identification of a novel cannabimimetic phenylacetylindole, cannabipiperidiethanone, as a designer drug in a herbal product and its affinity for cannabinoid CB₁ and CB₂ receptors". Chemical & Pharmaceutical Bulletin. 59 (9): 1203–5. doi:10.1248/cpb.59.1203. PMID21881274.