Macagigantin, a farnesylated flavonol from Macaranga gigantea

A new farnesylated flavonol derivative, macagigantin (1), together with two known flavonoids, glyasperin A (2) and apigenin (3), had been isolated from the acetone extract of the leaves of Macaranga gigantea. The structure of the new compound was elucidated as 6-farnesylkaempferol based on its spectroscopic data, including UV, IR, 1D and 2D NMR, and HR-EI-MS spectra. Compounds 1-3 were evaluated for their cytotoxic properties against P-388 cells, their IC50 values being 11.3, 6.0, and 5.1 mu M, respectively.