Compounds 1−15 were evaluated for their in vitro cytotoxicity against five human cancer cell
lines and the Beas-2B immortalized (noncancerous) human bronchial epithelial cell line. Compounds 1, 2, 9, and 14 exhibited
cytotoxicity with IC50 values ranging from 0.81 to 13 μM with selectivity indices as high as 10 when compared to the Beas-2B cell
line.