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Central nervous system drugs

Tolcapone

Also known as Tasmar, 3,4-Dihydroxy-4'-methyl-5-nitrobenzophenone, Ro 40-7592

CAS 134308-13-7Formula C14H11NO5Molar mass 273.24 g/molEC 694-343-9
GHS signal word: Warning. Pictograms: Hazardous to the environment 92 suppliers listed Drug substance
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Tolcapone chemical structure, C14H11NO5, CAS 134308-13-7
2D chemical structure

Key facts

What buyers check first

All properties
CAS number
134308-13-7
Formula
C14H11NO5
Molar mass
273.24 g/mol
EC number
694-343-9
HS code
291479
Category
Central nervous system drugs

What is Tolcapone?

Plain description, key identifiers and synonyms

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 catechols and a member of 2-nitrophenols.

Identifiers

Registry numbers, names and line notations, tap to copy

IUPAC name
(3,4-dihydroxy-5-nitrophenyl)-(4-methylphenyl)methanone
CAS number
134308-13-7 CAS number cross-checked
EC number
694-343-9
Molecular formula
C14H11NO5
UNII
CIF6334OLY
MDL number
MFCD00866569
InChIKey
MIQPIUSUKVNLNT-UHFFFAOYSA-N
InChI
InChI=1S/C14H11NO5/c1-8-2-4-9(5-3-8)13(17)10-6-11(15(19)20)14(18)12(16)7-10/h2-7,16,18H,1H3
SMILES (canonical and isomeric)
CC1=CC=C(C=C1)C(=O)C2=CC(=C(C(=C2)O)O)[N+](=O)[O-]

Synonyms

  • Tasmar
  • 3,4-Dihydroxy-4'-methyl-5-nitrobenzophenone
  • Ro 40-7592
  • (3,4-Dihydroxy-5-nitrophenyl)(4-methylphenyl)methanone
  • Ro-40-7592
  • (3,4-dihydroxy-5-nitrophenyl)-(4-methylphenyl)methanone
  • Methanone, (3,4-dihydroxy-5-nitrophenyl)(4-methylphenyl)-
  • Tolcapona
  • 5-(4-methylbenzoyl)-3-nitrobenzene-1,2-diol
  • 3,4-dihydroxy-5-nitro-4'-methylbenzophenone
  • 4'-methyl-3,4-dihydroxy-5-nitrobenzophenone
  • 5-[(4-Methylphenyl)carbonyl]-3-nitrobenzene-1,2-diol
  • 5-((4-methylphenyl)carbonyl)-3-nitrobenzene-1,2-diol
  • Tolcaponum
  • Ro 407592
  • Methanone,(3,4-dihydroxy-5-nitrophenyl)(4-methylphenyl)-
  • Ro 40 7592
  • 3,4 Dihydroxy 5' methyl 5 nitrobenzophenone
  • (3,4-dihydroxy-5-nitrophenyl)(p-tolyl)methanone
  • Tolcapone, >=98% (HPLC)
  • 3,4-dihydroxy-4 inverted exclamation mark -methyl-5-nitrobenzophenone
  • Tolcapone (usp monograph)
  • Talcapone
  • Tasmar (TN)
  • Tolcapone?
Show all 28 synonyms
  • TCW
  • (3,4-dihydroxy-5-nitro-phenyl)-(p-tolyl)methanone
  • Tolcapone (Standard)

Physical and chemical properties

Measured values and descriptors computed from the structure

Physical and chemical properties

Measured values, check the supplier specification for your grade

No measured properties are recorded for this substance yet. Ask suppliers for a technical data sheet.

Values vary by grade. Ask suppliers for the COA or TDS of the batch you buy.

Computed descriptors

Calculated from the structure, useful for screening and formulation

Molecular weight
273.24 g/molcalc.
Exact mass
273.0637 Dacalc.
LogP (octanol/water)
2.55calc.
Topological polar surface area
100.7 Ųcalc.
Hydrogen bond donors
2calc.
Hydrogen bond acceptors
5calc.
Rotatable bonds
3calc.
Heavy atoms
20calc.
Rings
2calc.
Aromatic rings
2calc.
Fraction sp3 carbons
0.07calc.
Formal charge
0calc.
Stereocentres
0calc.
Lipinski rule of five
Passes (0 violations)calc.

Calculated for screening. Confirm critical figures with the supplier.

Murcko scaffold

The ring system that remains when every side chain is removed

Murcko scaffold of this chemical, O=C(c1ccccc1)c1ccccc1

O=C(c1ccccc1)c1ccccc1

2 rings, 14 atoms, the Benzophenone ring system.

5,108 other chemicals share this scaffold

Safety and hazards

GHS classification summary, not a safety data sheet

GHS signal word
Warning
GHS09: Hazardous to the environment
Hazardous to the environment

Hazard statements

  • H400Very toxic to aquatic life.
Precautionary statements (3)
  • P273Avoid release to the environment.
  • P391Collect spillage.
  • P501Dispose of contents and container in accordance with local regulations.

GHS classification summary, not a safety data sheet (SDS). Classifications can differ by supplier, grade and concentration. Always check the supplier's SDS.

Full safety data and first aid

Tolcapone suppliers

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All 92 suppliers
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Where suppliers are based

92 suppliers in 15 countries

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Tolcapone price

Indicative price range per kg from live supplier offers

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Uses and applications

What the substance is used for, by industry and function

Industries and functions

Pharmacological actions

  • Antiparkinson Agents
  • Catechol O-Methyltransferase Inhibitors

Roles

  • antidyskinesia agent
  • antineoplastic agent
  • antiparkinson drug
  • antipsychotic agent
  • central nervous system depressant
  • central nervous system drug
  • enzyme inhibitor
  • neuroprotective agent
  • pharmaceutical
  • protective agent
  • psychotropic drug
  • tranquilizing drug

Pharmacology

Tolcapone is a Catechol-O-Methyltransferase Inhibitor. The mechanism of action of tolcapone is as a Catechol O-Methyltransferase Inhibitor.

Regulatory status

Inventories, regulations and trade controls that list this substance

Health and food

  • Active ingredient in FDA approved drug labels

HS code and trade data

Customs classification and reported world trade statistics

Global trade

World import and export statistics for the HS code Tolcapone is traded under.

HS 2914.79Indicative HS code

Halogenated, sulphonated, nitrated or nitrosated derivatives, other

World exports in 2024
$558M
−12.1% vs 2023, imports $608M
2019 to 2024
Top exporters
  1. China41.2%
  2. India * partner reported28.7%
  3. Germany16.7%
Top importers
  1. United States29.1%
  2. Italy9.9%
  3. Switzerland * partner reported8.8%

* Partner reported figures, a lower bound.

Reported customs values in USD, not prices.Full trade data

The HS code shown for Tolcapone is indicative (it was assigned by structure rules). Confirm the classification with your customs broker before shipping.

Frequently asked questions

Quick answers about Tolcapone, based on the data on this page

What is Tolcapone?

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.

What is the CAS number of Tolcapone?

The CAS registry number of Tolcapone is 134308-13-7.

What is the molecular formula and weight of Tolcapone?

The molecular formula of Tolcapone is C14H11NO5 and its molar mass is 273.24 g/mol.

What is Tolcapone used for?

Known uses and roles of Tolcapone include cns agents in pharmaceuticals, antidyskinesia agent, antineoplastic agent, antiparkinson drug, antipsychotic agent and 10 more.

Is Tolcapone hazardous?

Tolcapone carries the GHS signal word "Warning". Main hazards: very toxic to aquatic life. This summary is not an SDS, always read the supplier safety data sheet.

What is the HS code of Tolcapone?

Tolcapone is usually classified under HS code 291479 (Halogenated, sulphonated, nitrated or nitrosated derivatives, other). This is indicative, confirm it with your customs broker before shipping.

Where can I buy Tolcapone?

CompoundList lists 92 suppliers of Tolcapone in United States, China, United Kingdom, India and 11 more. Send one free request to get and compare quotes. Your contact details stay private until you accept a quote.

Where can I buy Tolcapone in India?

5 suppliers in India list Tolcapone on CompoundList. Filter the suppliers list by country and send a request to compare prices, grades and delivery times.

What is the price of Tolcapone?

Suppliers quote Tolcapone on request because prices depend on grade, purity, quantity and destination. A free request on CompoundList gets you several quotes to compare.

Guides for buyers

Practical guides that help when you source, ship or handle Tolcapone

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Data last updated 7 Oct 2026. Details may have changed, please confirm them with the supplier. Report an error on this page
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