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2. und , Eds., The Chemistry and Biology of Isoquinoline Alkaloids, Springer Verlag, Berlin 1985.
3. und , in The Chemistry of Heterocyclic Compounds; Isoquinoline, Ed., Vol. 50., Part 1, Seite 170, Wiley, New York, 1981.
4. , und , Dt. Patent 1795829 (1966), Hoechst AG, Frankfurt,