7-PET was discovered by K.W. Bentley and is a potent opioid analgesic drug, 300 times the potency of morphine by weight. It is related to the more well-known oripavine derivative opioid etorphine, which is used as a very potent veterinary painkiller and anesthetic medication, used primarily for the sedation of large animals such as elephants, giraffes and rhinos. 7-PET itself has a 3-O-methyl ether which reduces potency, but the 3-OH derivative is around 2200x morphine, almost the same potency as etorphine as a μ agonist, and unexpectedly the 3-desoxy compound is also around the same potency of 2000x morphine.