Morphinan derivatives--A review of the recent patent literature.

Alkaloids extracted from the Papaverum somniferum are among the most powerfully acting and clinically used drugs for diseases of the central nervous system, in particular for pain. The basic ring system, common to these opiate alkaloids, is the morphinan skeleton, which in the last 50 years has been chemically manipulated to obtain compounds with improved potency and increased selectivity toward different populations of opioid receptors. Despite a huge amount of research, interest surrounding these compounds is still high. This review will discuss the patent applications published from January 2001 to June 2002, focusing on new chemical entities that could become drugs over the next few years, new chemical processes for the production of the morphinans currently used in therapy, novel formulations and combined compositions.