Tubulin polymerization-IN-71 (Compound 4k) is an inhibitor for tubulin polymerization with an IC 50 of 3.06 μM. Tubulin polymerization-IN-71 inhibits the proliferation of cancer cell MG-63 and U2OS with IC 50 of 0.08-0.14 μM. Tubulin polymerization-IN-71 arrests the cell cycle at G2/M phase, and induces apoptosis in MG-63.