cypenamine cypenamine cypenamine (inn, ban), or cypenamine hydrochloride (usan), also known as 2-phenylcyclopentylamine, is a psychostimulant drug which was developed by a group at the william s. merrell chemical company in the 1940s. it is currently known only in scientific research and has never been developed for market use. cypenamine is currently legal throughout the entire world, and though its chemical structure has a vague similarity to certain controlled stimulants like fencamfamine, it is likely that it is too distant for it to be considered an illicit analogue under the united states federal analogue act of the controlled substances act. cypenamineclinical dataother names2-phenylcyclopentanamineatc codenoneidentifiers iupac name (±)-trans-2-phenylcyclopentan-1-amine cas number15301-54-9 ypubchem cid21786chemspider20476 yuniivp9115827hchemblchembl2110918comptox dashboard (epa)dtxsid40546452 chemical and physical dataformulac11h15nmolar mass161.248 g·mol−13d model (jsmol)interactive imagechiralityracemic mixture smiles n1ccc1c2=cc=cc=c2 inchi inchi=1s/c11h15n/c12-11-8-4-7-10(11)9-5-2-1-3-6-9/h1-3,5-6,10-11h,4,7-8,12h2 ykey:vngytynuzhdmpp-uhfffaoysa-n y (verify) chemistry stereochemistry 2-phenylcyclopentan-1-amine is a compound with two stereocenters. thus, the following two enantiomeric pairs may exist: (1rs,2sr)-trans-2-phenylcyclopentan-1-amine (1rs,2rs)-cis-2-phenylcyclopentan-1-amine the racemate (±)-trans-2-phenylcyclopentan-1-amine is the active ingredient of cypenamine. furthermore, the kinetic resolution of (±)-trans-2-phenylcyclopentan-1-amine by lipase b from candida antarctica may be effectively performed by an aminolysis reaction. racemic cis-2-phenylcyclopentan-1-amine has found no pharmacological application. homology cypenamine is a homolog of tranylcypromine, containing an expanded alicyclic ring that is two methylene units larger than the highly strained/reactive cyclopropane. the cyclohexane homologue has been reported, although the ld50s were all less than for plain amphetamine, it was still a functional stimulant.