HDAC6-IN-49 (Compound 3) is an inhibitor for HDAC with IC 50 of 0.012 and 0.735 μM for HDAC6 and HDAC1. HDAC6-IN-49 also exhibits inhibitory activities against MAO-B , cholinesterase (ChE) , histamine receptor (H3R) and serotonin 6 receptor (5-HT6R). HDAC6-IN-49 exhibits neuroprotective efficacy on SH-SY5Y cell. HDAC6-IN-49 improves cognitive function and locomotor ability in Drosophila Parkinson's disease models and in C. elegans Alzheimer's disease models.