Inhibition of TDP1 by 3, 4, 10 and 11. (A) Representative gel for inhibition of TDP1-catalyzed hydrolysis by 4 and 3: lane 1, N14Y only; lane 2, N14Y and TDP1; lanes 3–10, 3-fold serial dilutions of 4 from 10 mM to 5 μM; lanes 11–18, 3-fold serial dilutions of 3 from 10 mM to 5 μM. (B) Representative gel for inhibition of TDP1-catalyzed hydrolysis by 10 and 11: lane 1, N14Y only; lane 2, N14Y and TDP1; lanes 3–10, 3-fold serial dilutions of 10 from 10 mM to 5 μM; lanes 11–18, 3-fold serial dilution of 11 from 10 mM to 5 μM.