Abstract
[2-3H]Oripavine was administered to mature Papaver somniferum plants from two different chemical strains, one of which was known to contain oripavine.
Morphinone was synthesized and used as carrier. Incorporation of oripavine into morphine
was 28.1% and 21.4%, respectively. Morphinone decomposed during isolation, but the
small amount isolated from one batch showed an incorporation of 4.5%. Thebaine and
codeine were not radioactive. Therefore, the 3-O-demethylation of thebaine is not
reversible. These results strongly suggest that oripavine represents a step on a second
pathway from the baine to morphine.
