The Biogenesis of Alkaloids: Vi. The Formation of Hordenine and N-Methyltyramine From Tyramine in Barley

Tyramine-α-C 14 , synthesized from C 14 -barium carbonate, was administered to sprouting barley and radioactive hordenine and N-methyltyramine isolated from the roots. Separation of these alkaloids by chromatography followed by degradation showed that all the activity was located in the α -carbon atom. The specific activity of the N-methyltyramine was about 10 times that of hordenine. From the results it is concluded that tyramine undergoes methylation in the barley root to N-methyltyramine and thence to hordenine.