Anti-platelet aggregation constituents from Gynura elliptica.

A p-hydroxyacetophenone-like derivative, (+)-gynunone, and a chromane, together with six known compounds were isolated from the CHCl3 fraction of the roots of Gynura elliptica. Their structures were determined by means of spectral analyses. Among the isolates, 6-acetyl-2,2-dimethylchroman-4-one and vanillin showed anti-platelet aggregation activity induced by arachidonic acid in vitro.