Antiplatelet Activities of Aporphine Alkaloids Isolated from Leaves of Magnolia obovata

Abstract

Five aporphine alkaloids, N-acetylanonaine (1), N-acetylxylopine (2), N-formylanonaine (3), liriodenine (4), and lanuginosine (5) as the antiplatelet constituents, were isolated from the methanol extract of leaves of Magnolia obovata. This is the first reported occurrence of 2 and 3 from genus Magnolia and 5 was isolated from this plant for the first time. Compounds 1, 2 and 3 showed 60 ∼ 264-fold stronger inhibitory effects than acetylsalicylic acid (ASA) to rat platelet aggregation induced by collagen, epinephrine, arachidonic acid (AA), or U46619.

References

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