Potent catechol O-methyltransferase (COMT) inhibitor (IC50 values are 14.3, 20.1 and 73.3 nM for rat liver soluble COMT, total COMT and membrane-bound COMT respectively). Increases bioavailability of levodopa when given as an adjunct therapy for Parkinson's disease. Inhibits α-synuclein aggregation in an in vitro assay; blocks α-synuclein-induced cell death in PC-12 cells. Purity 99%. MW (observed): 305.29