Glucosyloxy alkaloids from Pancratium biflorum

From fluids of flower stems and bulbs, and from extracts of roots of Pancratium biflorum, collected at different stages of growth, three new glucosyloxy alkaloids, viz. hordenine-4-O-β-d-glucoside, lycorine-1-O-β-d-glucoside and pseudolycorine-1-O-β-d-glucoside, have been isolated and characterized. Additionally, three proto alkaloids, β-phenethylamine, tyramine and hordenine, together with four true alkaloids, lycorine, pseudolycorine, pretazettine and tazettine, encountered before in other memebrs of the Amaryllidaceae, have now been isolated also from this species. Ontogenic variations of alkaloidal constituents have been observed. The ability of the alkaloidal constituents to complex with divalent metal ions and phytosterols has been examined with a view to evaluating their significance in plant biochemistry.     

Ontogenic variations in the alkaloids of Narcissus assoanus

The distribution and ontogenic variations in the five alkaloids previously isolated from Narcissus assoanus Duf. (pseudolycorine, two new acetylated derivatives: I-O-acetylpseudolycorine and 2-O-acetylpseudolycorine, and two phenanthridines: assoanine and oxoassoanine) were studied. The alkaloids have been separated and quantified by high performance liquid chromatography, and the free amino acids phenylalanine and tyrosine were also analyzed. Comparing the results obtained for aerial parts and bulbs, we suggest that alkaloids are synthesized in the aerial part of the plant, and propose a likely biosynthetic pathway.