Viminol Explained

Viminol (marketed under the brandname Dividol) is an opioid analgesic developed by a team at the drug company Zambon in the 1960s.^[1] Viminol is based on the α-pyrryl-2-aminoethanol structure, unlike any other class of opioids.^{[2] [3]}

Viminol has both antitussive (cough suppressing) and analgesic (pain reducing) effects. Viminol has additional effects similar to other opioids including sedation and euphoria. It has six different stereoisomers which have varying properties. Four are inactive, but the 1S-(R,R)-disecbutyl isomer is a μ-opioid full agonist around 5.5 times more potent than morphine and the 1S-(S,S)-disecbutyl isomer is an antagonist.^{[4] [5]} Since viminol is supplied as a racemic mixture of isomers, the overall effect is a mixed agonist–antagonist profile similar to that of opioids such as pentazocine, although with somewhat fewer side effects.^[6]

Side effects

Side effects are similar to other opioids, and can include:

• Itching
• Nausea
• Sedation
• Respiratory depression - can be potentially life-threatening

However, since viminol is supplied as a racemic mixture of agonist and antagonist isomers, the abuse potential and respiratory depression tends to be less than that of μ-opioid full agonist drugs.

Drug dependence may occur.^[7]

Related compounds

Later work showed that replacing the chlorine atom with an fluorine atom (2F-Viminol) or with a trifluoromethyl group produced a compound with twice the potency and half the acute toxicity.^[8] A later team at Zambon found that one isomer of a pyrrolidone analog is 318 times as potent as morphine in its analgesic activity in animal studies.^[9] A number of related compounds were also found to be active, allowing a QSAR model to be constructed.

Notes and References

1. 1-(α-Pyrryl)-2-amino Ethanols . US . 3539589 . Whitefin Holding SA . 10 November 1970 . Teotino UM, Bella DD .
2. Contri AM . [Chromatographic separation of diastereoisomers of aminoalcohol salts and their densitometric determination] . Italian . Il Farmaco; Edizione Pratica . 36 . 4 . 215–22 . April 1981 . 6894429 .
3. Neto JM, Murad JE, Monteiro SS . Psychopharmacological properties of the viminol-p-hydroxybenzoate . Revista Brasileira de Pesquisas Medicas e Biologicas . 10 . 6 . 361–8 . December 1977 . 609773 .
4. Stereoisomers of 1(1'(-O-Chlorobenzyl)-2'-Pyrryl)-2-Disec.Butylamino-Ethanol . US . 3857857 . Whitefin Holding SA . 31 December 1974 . Della D, Bella CV, Monza DC, Tiotino UM .
5. Shook JE, Kallman MJ, Dewey WL . The discriminative stimulus properties of the R2 isomer of viminol . Pharmacology, Biochemistry, and Behavior . 20 . 1 . 59–62 . January 1984 . 6546450 . 10.1016/0091-3057(84)90101-1 . 11418389 .
6. Cinelli M, Costa V, Ventresca GP, Lodola E . Viminol R2 analgesic activity in patients with postoperative pain: comparison with pentazocine . International Journal of Clinical Pharmacology, Therapy, and Toxicology . 24 . 5 . 232–5 . May 1986 . 3525423 .
7. 10.1080/14659890701237124. Dependence on Viminol. Journal of Substance Use. 12. 4. 301–305. 2009. Turkiewicz G, Baltieri DA . 71184621.
8. Stereoisomers of 1-(1'benzyl-2'pyrryl)-2-di-sec.-butylaminoethanol and pharmaceutical compositions comprising same . US . 4148907 . Etablissement Viridis . 10 April 1979 . Conti F .
9. Pyrrolidone-2 compounds and their use for central analgesic activity . US . 4960788 . Zambon Group S.P.A. . 2 October 1990 . Carenzi A, Chiarino D, Bella DD, Grancini GC, Veneziani C .