Biosynthesis of the Ergoline System

Incorporation of tryptophan labeled in different positions into the ergot alkaloids was consistent with the contribution of tryptophan to the ergoline 

Baxter s group (Baxter et al., 1964) found that the incorporation of (l)-methionine was four times the incorporation of [ Cjformate into festuclavine. The label from methionine was shown by degradation experiments to be located exclusively in the A -methyl group of festuclavine. (L)-[m r/zj /- C, H]Methionine was incorporated into the alkaloid without change in the ratio. The methyl goup of methionine is therefore 

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