ROLE OF 1,2-DEHYDRORETICULINIUM ION IN BIOSYNTHETIC CONVERSION OF RETICULINE TO THEBAINE

The role previously assigned to 1, 2-dehydroreticulinium ion as a precursor to the morphinan alkaloids in Papaver somniferum was based on feeding experiments with a synthetic compound of uncertain identity. We have now prepared authentic 1, 2-dehydroreticulinium chloride and shown its efficient incorporation into the morphinan alkaloids, supporting the previous hypothesis. Moreover, using a double-label technique and steady-state 14CO2 biosynthesis, we have determined that 1, 2-dehydroreticulinium ion is a natural product whose native pool size is about one-fifth that of reticuline. These data clearly establish 1, 2-dehydroreticulinium ion as an intermediate in morphinan alkaloid biosynthesis. © 1978, American Chemical Society. All rights reserved.