3-(3-{1-[1-(4-Chlorophenyl)ethyl]piperidin-4-yl}-2-oxo-2,3-dihydro-1H-1,3-benzimidazol-1-yl)propanenitrile, commonly known as cychlorphine, is a piperidine benzimidazolone and synthetic opioid belonging to the orphine opioids, a group of related new synthetic opioids. Cychlorphine is structurally related to brorphine and bezitramide, both of which are controlled under Schedule I of the United Nations 1961 Single Convention on Narcotic Drugs because of the public health and social risks they pose.

Cychlorphine is monitored by the EUDA as a new psychoactive substance through the European Union Early Warning System (EWS), in accordance with Regulation (EU) 2023/1322 (1).

Since 2024, a marked increase has been observed in the number of orphine opioids identified on the European drug market, with nine new substances reported, including cychlorphine.