Viminol

Viminol (marketed under the brandname Dividol) is an opioid analgesic developed by a team at the drugs company Zambon in the 1960s. Viminol is based on the α-Pyrryl-2-Amino-Ethanol structure unlike any other class of opioids;
Viminol has both antitussive (cough suppressing) and analgesic (pain reducing) effects. It has six different stereoisomers which have varying properties. 4 are inactive, the 1S-(R,R)-disecbutyl isomer being a μ-opioid full agonist around 5.5 times more potent than morphine while the 1S-(S,S)-disecbutyl isomer is an antagonist. Since vimonol is supplied as a racemic mixture of isomers, the overall effect produces a mixed agonist–antagonist profile similar to that of opioids such as pentazocine, although with somewhat fewer side effects.