Table 5. Results of the MTT-Based Efficacy Assays^2,55−59 Using the Antineoplastic Agent 33 Either without or in Combination with Either Compound 24 or 30 at Concentrations of 1.0, 2.0, 3.5, and 5.0 μM against ABCB1-Expressing A2780/ADR Cells Compared to the Effect of 33 Alone on Sensitive A2780 Cells^a.

no.	A2780/ADRcell toxicity 33 +0.0 μM cmpd.GI50 ± SEM [nM]	A2780/ADRcell toxicity 33 +1.0 μM cmpd.GI50 ± SEM [nM]	A2780/ADRcell toxicity 33 +2.0 μM cmpd.GI50 ± SEM [nM]	A2780/ADRcell toxicity 33 +3.5 μM cmpd.GI50 ± SEM [nM]	A2780/ADRcell toxicity 33 +5.0 μM cmpd.GI50 ± SEM [nM]	A2780 cell toxicity 33 +0.0 μM cmpd.GI50 ± SEM [nM]
24	802 ± 81	332 ± 50	214 ± 10	110 ± 1	32.2 ± 0.6	19.4 ± 1.7
30	802 ± 81	516 ± 45	165 ± 24	32.4 ± 3.1	12.9 ± 3.5	19.4 ± 1.7

^aDMSO and culture medium were used to define 0% and 100%, respectively. GI₅₀ values ± SEM of at least three independent experiments are shown.