Notes: BTB-1 is a reversible inhibitor of the kinesin-8 family motor protein Kif18A (IC50 = 1.69 μM).{46312} It is selective for Kif18A over a panel of seven kinesins at 100 μM. BTB-1 (100 μM) inhibits Kif18A-dependent microtubule motility in a microtubule gliding assay. It induces mitotic accumulation of HeLa cells in a dose-dependent manner.