Inhibition of Platelet-Activating Factor Receptor Binding by Aporphine and Phenanthrenoid Alkaloids from Aromadendron elegans

Abstract

Six aporphine and one phenanthrenoid alkaloids isolated from Aromadendron elegans Blume were investigated for their inhibitory effect on platelet-activating factor (PAF) binding to rabbit platelets using ³ H-PAF as a ligand. Of the compounds tested, (-)-N-acetylanonaine, 1-(N-acetyl-N-methylamino)ethyl-3,4,6-trimethoxy-7-hydroxy-phenanthrene, and predicentrine showed strong inhibition of PAF receptor binding, with IC₅₀ values of 52.4, 38.6, and 29.8 μM, respectively. The flexibility of the biphenyl system of the aporphine and the presence of methoxy groups at C-9 and C-10 were all preferable in binding to the receptor.

References

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