DDO-2728 (compound 19) is a selective AlkB homologue 5 (ALKBH5) inhibitor with an IC 50 of 2.97 μM. DDO-2728 increases the abundance of N 6 methyladenosine (m 6 A) modifications, inducing cell apoptosis and cycle arrest. DDO-2728 suppresses tumor growth in the MV4−11 xenograft model with favorable safety profile, shows the potential of targeting ALKBH5 in cancer research.