Tubulin polymerization-IN-64 (Compound 8a) is an inhibitor for tubulin polymerization by occupying the colchicine binding site of tubulin, with IC 50 of 6.9 μM. Tubulin polymerization-IN-64 inhibits proliferations of cancer cells A549, HeLa, HCT116 and HT-29, with IC 50 s of 2.42, 10.33, 6.28, 5.33 μM, respectively. Tubulin polymerization-IN-64 arrests cell cycle at G2/M phase, induces apoptosis in A549.