SSAO inhibitor-3 (Compound 2) is a semicarbazide-sensitive amine oxidase ( SSAO ) inhibitor with IC 50 s of <10 nM, and 0.1-10 μM for human SSAO and AOC1, respectively. SSAO inhibitor-3 can be used for the research of atherosclerosis, diabetes and its complications, obesity, stroke, chronic kidney disease, retinopathy, chronic obstructive pulmonary disease (COPD), autoimmune diseases, multiple sclerosis, etc.