O-1656 is a cannabinoid agonist which was invented by Billy R Martin and Raj K Razdan at Organix Inc in 2002. It is moderately selective for the CB<sub>2</sub> receptor with a CB<sub>1</sub> receptor affinity of 18 nM and a CB<sub>2</sub> receptor affinity of 2 nM. Since it has a cycloheptyl ring attached to the phenol core, it falls outside the definition of a "cyclohexylphenol derivative", but may still be controlled by generic legislation in some jurisdictions.