HDAC6-IN-5 (compound 11b) is a potent and BBB-penetrated inhibitor of HDAC6 (IC50 = 0.025 µM) that inhibits Abeta 1-42 self-aggregation and AChE with IC50 values of 3.0 and 0.72 µM, respectively. Additionally, HDAC6-IN-5 can enhance neurite outgrowth without significant neurotoxicity.