Studies on constituents of fruit body of Polyporus umbellatus and their cytotoxic activity.

From the crude drug Chorei, the fruit body of Polyporus umbellatus, seven new components named polyporusterone A, B, C, D, E, F and G, were isolated and their structures were determined on the basis of the spectral data. These compounds showed cytotoxic action on leukemia 1210 cell proliferation.