Sulfonamide derivatives have been designed and synthesized for LIMK2 inhibitors. The inhibition activities of the sulfonamide derivatives were tested against LIMK2. The best sulfonamide derivative was three times more potent than the best sulfonamide inhibitors previously published based on MTT assay results. Two LIMK2 single mutants, LIMK2-365 and LIMK2-549, and a LIMK2 double mutant (LIMK2-DM) were cloned, and their phosphorylation activities were measured and compared against normal LIMK2. LIMK2-365, LIMK2-549, and LIMK2-DM all showing lower activities than the normal LIMK2, with the LIMK2-DM showing even lower activity than each of the single mutant LIMK2, suggesting the importance of these amino acid residues in phosphorylation and in the formation of dimer LIMK2.