Stylopine, Chelidonine, and Related Alkaloids

Stylopine, Chelidonine, and Related Alkaloids.—Full details have been published on a study of the biosynthesis of stylopine (71) and chelidonine (76) in Chelidonium majus. The original publications predate these reports so it is fitting that the work be summarized here. In any case some of the results are new and the work is notable for the rigour of its approach and the elegant application of tritium labelling as a probe for the course of the reactions involved. The results obtained with the R and S isomers of multiple labelled reticuline [as (67)] and scoulerine [as (68)] establish the biosynthetic sequence as (67) - (68) (71) - (76) (-)-(5)-scoulerine was shown 

The methylenedioxy-group on ring D of stylopine was shown to arise from the ortho-hydroxy-methoxy-system of reticuline as in other cases e.g. refs. 77 and 78). 

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