Tolcapone

Yellow SolidTolcapone, 3,4-dihydroxy-4'-methyl-5-nitrobenzophenone (Tasmar), is a yellow, odorless, nonhygroscopic,crystalline compound (pKa＝4.78). Tolcapone israpidly absorbed after oral administration. Tolcapone ishighly bound to plasma albumin (＞98%), and its distributionis therefore restricted. Tolcapone has low first-pass metabolism.It is almost completely metabolized in the liver before excretion, and 60% is excreted by the kidney.
Solid
Tolcapone is benzophenone substituted on one of the phenyl rings at C-3 and C-4 by hydroxy groups and at C-5 by a nitro group, and on the other phenyl ring by a methyl group at C-4. It is an inhibitor of catechol O-methyltransferase. It has a role as an EC 2.1.1.6 (catechol O-methyltransferase) inhibitor and an antiparkinson drug. It is a member of benzophenones, a member of 2-nitrophenols and a member of catechols.|Tolcapone is a drug that inhibits the enzyme catechol-O-methyl transferase (COMT). It is used in the treatment of Parkinson's disease as an adjunct to levodopa/carbidopa medication. It is a yellow, odorless, non-hygroscopic, crystalline compound. Tolcapone is associated with a risk of hepatotoxicity.|Tolcapone is a Catechol-O-Methyltransferase Inhibitor. The mechanism of action of tolcapone is as a Catechol O-Methyltransferase Inhibitor.|Tolcapone is a catechol-O-methyltransferase inhibitor used in the therapy of Parkinson disease as adjunctive therapy in combination with levodopa and carbidopa. Tolcapone has been associated with serum enzyme elevations during treatment and with several instances of clinically apparent acute liver injury, which can be severe and even fatal.|Tolcapone is a benzophenone derivative and a catechol-O-methyltransferase (COMT) inhibitor. Tolcapone selectively and reversibly inhibits COMT, an enzyme that catalyzes the metabolism of biologically active catechols and their hydroxylated metabolites by transferring the methyl group of S-adenosyl-L-methionine to the phenolic group of catechol-containing substrates. When given in conjunction with a peripheral dopa decarboxylase inhibitor and levodopa, tolcapone may prevent the metabolism of levodopa to 3-methoxy-4-hydroxy- L-phenylalanine (3-OMD) in the brain and peripheral tissues leading to increased bioavailability and enhancement of delivery to the central nervous system (CNS) of levodopa.|A benzophenone and nitrophenol compound that acts as an inhibitor of CATECHOL O-METHYLTRANSFERASE, an enzyme involved in the metabolism of DOPAMINE and LEVODOPA. It is used in the treatment of PARKINSON DISEASE in patients for whom levodopa is ineffective or contraindicated.