AChE/BChE/MAO-B-IN-4, an indan-1-one derivative, is a potent MAO-B inhibitor with an IC 50 of 0.0393 μM for human MAO-B. AChE/BChE/MAO-B-IN-4 is a potent AChE and BChE enzyme inhibitor, with IC 50 s of 0.0458 μM and 0.075 μM for human AChE and BChE enzyme, respectively. AChE/BChE/MAO-B-IN-4 shows significant antioxidant activity and prevent β-amyloid plaque aggregation. AChE/BChE/MAO-B-IN-4 has the potential for Alzheimer's disease (AD) research.