CompoundList
Sign in
Direct dyes

Thioflavin S

Also known as C.I. Direct Yellow 7, Direct yellow 7, Chromine g

CAS 1326-12-1Formula C25H24ClN3O3S3Molar mass 546.14 g/molEC 215-418-0
GHS signal word: Warning. Pictograms: Harmful or irritant 1 supplier listed
Get quotes See the supplier
Thioflavin S chemical structure, C25H24ClN3O3S3, CAS 1326-12-1
2D chemical structure

Key facts

What buyers check first

All properties
CAS number
1326-12-1
Formula
C25H24ClN3O3S3
Molar mass
546.14 g/mol
EC number
215-418-0
HS code
320414
Category
Direct dyes

What is Thioflavin S?

Plain description, key identifiers and synonyms

Thioflavin S is a chemical substance with the molecular formula C25H24ClN3O3S3 and a molar mass of 546.14 g/mol. Its CAS registry number is 1326-12-1. The IUPAC name is 2-[2-[4-(dimethylamino)phenyl]-3-methyl-1,3-benzothiazol-3-ium-6-yl]-3,6-dimethyl-1,3-benzothiazol-3-ium-7-sulfonate chloride.

Identifiers

Registry numbers, names and line notations, tap to copy

IUPAC name
2-[2-[4-(dimethylamino)phenyl]-3-methyl-1,3-benzothiazol-3-ium-6-yl]-3,6-dimethyl-1,3-benzothiazol-3-ium-7-sulfonate chloride
CAS number
1326-12-1 CAS number cross-checkedOther or deprecated CAS: 401813-29-4
EC number
215-418-0
Molecular formula
C25H24ClN3O3S3
UNII
FDK4QJ64TS
InChIKey
VNVDHTWVCQCPLI-UHFFFAOYSA-M
InChI
InChI=1S/C25H24N3O3S3.ClH/c1-15-6-12-20-22(23(15)34(29,30)31)33-25(28(20)5)17-9-13-19-21(14-17)32-24(27(19)4)16-7-10-18(11-8-16)26(2)3;/h6-14H,1-5H3;1H/q+1;/p-1
SMILES (canonical and isomeric)
CC1=C(C2=C(C=C1)[N+](=C(S2)C3=CC4=C(C=C3)[N+](=C(S4)C5=CC=C(C=C5)N(C)C)C)C)S(=O)(=O)[O-].[Cl-]

Synonyms

  • C.I. Direct Yellow 7
  • Direct yellow 7
  • Chromine g
  • Direct flavine s
  • CI 49010
  • C.I. 49010
  • Brilliant yellow s
  • thioflavine S
  • Thioflavin S2
  • 2,6'-Bibenzothiazolium, 2'-(4-(dimethylamino)phenyl)-3,3',6-trimethyl-7-sulfo-, inner salt, chloride

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
546.14 g/molcalc.
Exact mass
545.0668 Dacalc.
LogP (octanol/water)
1.38calc.
Topological polar surface area
68.2 Ųcalc.
Hydrogen bond donors
0calc.
Hydrogen bond acceptors
6calc.
Rotatable bonds
4calc.
Heavy atoms
35calc.
Rings
5calc.
Aromatic rings
5calc.
Fraction sp3 carbons
0.2calc.
Formal charge
0calc.
Stereocentres
0calc.
Components
2calc.
Lipinski rule of five
Passes (1 violation)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, c1ccc(-c2nc3ccc(-c4nc5ccccc5s4)cc3s2)cc1

c1ccc(-c2nc3ccc(-c4nc5ccccc5s4)cc3s2)cc1

5 rings, 24 atoms.

4 other chemicals share this scaffold

Safety and hazards

GHS classification summary, not a safety data sheet

GHS signal word
Warning
GHS07: Harmful or irritant
Harmful or irritant

Hazard statements

  • H315Causes skin irritation.
  • H319Causes serious eye irritation.
  • H335May cause respiratory irritation.
Precautionary statements (16)
  • P261Avoid breathing dust, fume, gas, mist, vapours or spray.
  • P264Wash skin thoroughly after handling.
  • P264 + P265Wash skin thoroughly after handling. Do not touch eyes.
  • P271Use only outdoors or in a well-ventilated area.
  • P280Wear protective gloves, protective clothing, eye protection and face protection.
  • P302 + P352If on skin: Wash with plenty of water.
  • P304 + P340If inhaled: Remove person to fresh air and keep comfortable for breathing.
  • P305 + P351 + P338If in eyes: Rinse cautiously with water for several minutes. Remove contact lenses, if present and easy to do. Continue rinsing.
  • P319Get medical help if you feel unwell.
  • P321Specific treatment (see supplemental first aid instructions on the label).
  • P332 + P317If skin irritation occurs: Get medical help.
  • P337 + P317If eye irritation persists: Get medical help.
  • P362 + P364Take off contaminated clothing. And wash it before reuse.
  • P403 + P233Store in a well-ventilated place. Keep container tightly closed.
  • P405Store locked up.
  • 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

Thioflavin S suppliers

Sponsored listings first, then the documented ranking: membership, verification, replies, completeness, freshness and ratings

See the supplier
  • AAT Bioquest
    United States, PleasantonUnclaimed profile
    Thioflavin SGrade, purity and minimum order on request
    Price on request
    View

Suppliers marked Unclaimed profile have not claimed their profile yet. They are not verified by CompoundList, their offers are price on request and details may have changed, so please confirm them with the supplier. Company representatives can claim a profile with a business email on the company's own website domain. Our team verifies each claim and sends the result by email.

Where suppliers are based

1 supplier in 1 country

Send one request to many suppliers

Choose up to 10 suppliers or let us match your request. Compare quotes side by side, free.

Choose suppliersPost a request

Thioflavin S price

Indicative price range per kg from live supplier offers

No published prices right now

Suppliers quote this chemical on request. Send one free request and compare quotes side by side.

Get latest price

Uses and applications

What the substance is used for, by industry and function

Roles

  • dye
  • fluorescent dye
  • fluorochrome
  • histological dye

Regulatory status

Inventories, regulations and trade controls that list this substance

United States

  • TSCA inventory (USA)
    Status: Active in US commerce

HS code and trade data

Customs classification and reported world trade statistics

Global trade

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

HS 3204.14Indicative HS code

Direct dyes and preparations based thereon

World exports in 2024
$328M
−1.5% vs 2023, imports $336M
2019 to 2024
Top exporters
  1. India * partner reported34.9%
  2. China11.3%
  3. Spain9.0%
Top importers
  1. Italy9.8%
  2. Germany8.7%
  3. Netherlands7.8%

* Partner reported figures, a lower bound.

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

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

Frequently asked questions

Quick answers about Thioflavin S, based on the data on this page

What is Thioflavin S?

Thioflavin S is a chemical substance with the molecular formula C25H24ClN3O3S3 and a molar mass of 546.14 g/mol. Its CAS registry number is 1326-12-1. The IUPAC name is 2-[2-[4-(dimethylamino)phenyl]-3-methyl-1,3-benzothiazol-3-ium-6-yl]-3,6-dimethyl-1,3-benzothiazol-3-ium-7-sulfonate chloride.

What is the CAS number of Thioflavin S?

The CAS registry number of Thioflavin S is 1326-12-1. Other or deprecated CAS numbers: 401813-29-4.

What is the molecular formula and weight of Thioflavin S?

The molecular formula of Thioflavin S is C25H24ClN3O3S3 and its molar mass is 546.14 g/mol.

What is Thioflavin S used for?

Known uses and roles of Thioflavin S include textile dyes in textiles and leather, indicators and stains in research and laboratory, dye, fluorescent dye, fluorochrome and 1 more.

Is Thioflavin S hazardous?

Thioflavin S carries the GHS signal word "Warning". Main hazards: causes skin irritation, causes serious eye irritation, may cause respiratory irritation. This summary is not an SDS, always read the supplier safety data sheet.

What is the HS code of Thioflavin S?

Thioflavin S is usually classified under HS code 320414 (Direct dyes and preparations based thereon). This is indicative, confirm it with your customs broker before shipping.

Where can I buy Thioflavin S?

CompoundList lists 1 supplier of Thioflavin S in United States. Send one free request to get and compare quotes. Your contact details stay private until you accept a quote.

What is the price of Thioflavin S?

Suppliers quote Thioflavin S 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 Thioflavin S

Get quotes for Thioflavin S

Post one free request with your grade, quantity and destination. Matching suppliers send quotes you can compare side by side.
Post a request Sell Thioflavin S
Data last updated 7 Oct 2026. Details may have changed, please confirm them with the supplier. Report an error on this page
Embed this structure on your websiteShow code

Paste this code into your page to show the 2D structure of Thioflavin S with a 3D view, its CAS number where known and a link back to this page. Free to use with the link kept.

<iframe src="https://www.compoundlist.com/embed/structure/thioflavin-s-1326-12-1" title="Thioflavin S structure on CompoundList" width="360" height="420" style="border:1px solid #E7E2DA;border-radius:12px;max-width:100%" loading="lazy" referrerpolicy="strict-origin-when-cross-origin"></iframe>
Preview the embed

Explore more in Direct dyes or HS code 320414

1 supplier
Free quotes, contact stays private
Get quotes