Table 2.
Inhibition of tubulin polymerization and colchicine binding by compounds 3c–d, 4b, 4e–g, 4i–j, 4l–m and CA4
| Compound | Tubulin assemblya IC50 ± SD (µM) |
Colchicine bindingb % ± SD |
|
|---|---|---|---|
| 1 µM drug |
5 µM drug |
||
| 3c | 1.3 ±0.1 | 60 ± 0.1 | n.d. |
| 3d | 2.1 ± 0.3 | 39 ± 1 | n.d. |
| 4b | 1.2 ± 0.07 | 49 ± 1 | 81 ±4 |
| 4e | 0.58 ± 0.02 | 60 ± 0.3 | 88 ± 0.5 |
| 4f | 0.63 ± 0.1 | 51 ± 2 | 88 ± 4 |
| 4g | 0.67 ± 0.1 | 85 ± 7 | 93 ± 5 |
| 4i | 0.92 ± 0.05 | 66 ± 4 | 92 ± 0.3 |
| 4j | 0.95 ± 0.06 | 54 ± 3 | 87 ± 1 |
| 4l | 0.93 ± 0.01 | n.d. | 75 ± 3 |
| 4m | 0.71 ± 0.1 | 48 ± 2 | 80 ± 1 |
| CA4 (1) | 1.0 ± 0.09 | 88 ± 1 | 99 ± 2 |
n.d.: not determined.
a
Inhibition of tubulin polymerization. Tubulin was at 10 µM.
b
Inhibition of [3H]colchicine binding. Tubulin was at 1 µM, colchicine was at 5 µM.