Recent developments in the chemistry of thebaine and its transformation products as pharmacological targets.

The most practical synthetic routes to the preparation of as important pharmaceuticals as oxycodone, naloxone, naltrexone, nalbuphine and buprenorphine have utilized the alkaloid, thebaine, as a starting material. This review intends to focus on chemical transformations of morphinans which resulted in morphinandiene derivatives with well-established and novel pharmacological potencies. These chemical transformations were mainly associated with the formation and substitution of the unique diene structure of the ring C of the morphinan backbone.