“…Coumarins comprise a very large class of compounds found throughout the plant kingdom (Egan et al, 1990). The biological activity of coumarins and more complex related derivatives appears to be based on the coumarin nucleus and several study reported the cytostatic activity of these natural products against neoplastic skin cell line (Jimenez-Orozco et al, 1999;Finn et al, 2001). On the basis of these studies we included in our work the furanocoumarin bergapten and the coumarin citropten derived from Citrus species.…”