Table 2.

Biological activities of compounds 1–3.

Compound	PDCD4 EC50 a (μg/mL)	PDCD4 EC90 a (μg/mL)	Cytotoxicity b (μg/mL)
1	1.8	-	4.2
2	2.8	5.5	17.0
3	n.a. c	-	10.6
Rapamycin d	0.02	0.1	>1.0

^a EC₅₀ and EC₉₀ values represent the minimum concentration required for 50% and 90% recovery of the PDCD4-luciferase signal from TPA-induced degradation; ^b Values presented as the minimum concentration required for total luciferase signal loss, relative to TPA treated control cells; ^c Not active; ^d Positive control, concentration in μM.