Table 1. IC₅₀ values of the compounds against tumor cells and normal human cells.

	Cytotoxic activity (IC50, μM)a
Compound	BGC-823b	A549b	HepG2b	HL-7720b
4-MP-PTOX	8.72 ± 3.15	1.12 ± 0.35	1.14 ± 1.07	11.30 ± 0.57
4-TG-PTOX	4.40 ± 1.55	0.57 ± 0.92	0.30 ± 0.34	13.51 ± 2.41
PTOX	18.32 ± 2.22	20.15 ± 2.75	8.36 ± 1.42	4.31 ± 1.46
Colchicines	12.17 ± 1.26	12.23 ± 0.76	13.22 ± 0.88	6.42 ± 1.03
Nocodazole	38.89 ± 3.12	27.44 ± 2.92	18.35 ± 3.71	8.51 ± 1.73

^aStandard deviation (SD) of triplicate samples was calculated from three independent samples, mean ± SD (n = 3)

^bMTT methods, drug exposure was for 48 h.