CompoundList
Sign in
Dye intermediates

H acid

Also known as 4-Amino-5-hydroxy-2,7-naphthalenedisulfonic acid, 2,7-Naphthalenedisulfonic acid, 4-amino-5-hydroxy-, 1-Amino-8-naphthol-3,6-disulfonic acid

CAS 90-20-0Formula C10H9NO7S2Molar mass 319.32 g/molEC 201-975-7
GHS signal word: Danger. Pictograms: Corrosive, Harmful or irritant 12 suppliers listed
Get quotes Compare 12 suppliers
H acid chemical structure, C10H9NO7S2, CAS 90-20-0
2D chemical structure

Key facts

What buyers check first

All properties
CAS number
90-20-0
Formula
C10H9NO7S2
Molar mass
319.32 g/mol
Physical form
Powder
HS code
292221
Category
Dye intermediates
Illustrative photo, drums, an IBC tote and sacks in a chemical warehouse in a warehouse
Typical packagingIllustrative packaging image, not the actual product

What is H acid?

Plain description, key identifiers and synonyms

H acid is a chemical substance with the molecular formula C10H9NO7S2 and a molar mass of 319.32 g/mol. Its CAS registry number is 90-20-0. The IUPAC name is 4-amino-5-hydroxynaphthalene-2,7-disulfonic acid.

Identifiers

Registry numbers, names and line notations, tap to copy

IUPAC name
4-amino-5-hydroxynaphthalene-2,7-disulfonic acid
CAS number
90-20-0 CAS number cross-checkedOther or deprecated CAS: 5460-09-3, 90431-97-3, 90432-00-1, 98072-99-2
EC numbers
201-975-7, 291-627-0, 291-630-7, 308-556-9
Molecular formula
C10H9NO7S2
UNII
4WUM31ES4U
MDL number
MFCD00035728
InChIKey
APRRQJCCBSJQOQ-UHFFFAOYSA-N
InChI
InChI=1S/C10H9NO7S2/c11-8-3-6(19(13,14)15)1-5-2-7(20(16,17)18)4-9(12)10(5)8/h1-4,12H,11H2,(H,13,14,15)(H,16,17,18)
SMILES (canonical and isomeric)
C1=C2C=C(C=C(C2=C(C=C1S(=O)(=O)O)N)O)S(=O)(=O)O

Synonyms

  • 4-Amino-5-hydroxy-2,7-naphthalenedisulfonic acid
  • 2,7-Naphthalenedisulfonic acid, 4-amino-5-hydroxy-
  • 1-Amino-8-naphthol-3,6-disulfonic acid
  • 1-Naphthol-8-amino-3,6-disulfonic acid
  • C.I. 35570
  • Sulfonphthol
  • 1-amino-8-nephthol-2, 2'-disulfonic acid
  • 4-amino-5-hydroxynaphthalene-2,7-disulfonic acid
  • H-Acid
  • 1-Amino-8-hydroxynaphthalene-3,6-disulphonic acid
  • Kyselina H
  • 4-amino-5-hydroxy-naphthalene-2,7-disulfonic acid
  • Kyselina 1-amino-8-naftol-3,6-disulfonova
  • 4-Amino-5-hydroxynaphthalene-2,7-disulphonic acid
  • Kyselina 8-amino-1-naftol-3,6-disulfonova
  • 1-naphthol-8-amino-3,6-disulfonicacid
  • 4-amino-5-hydroxy-7-naphthalenedisulfonicacid
  • 2, 4-amino-5-hydroxy-
  • 7-naphthalenedisulfonicacid,4-amino-5-hydroxy-2
  • 1-Amino-8-hydroxynaphthalene-3,6-disulfonic acid
  • 4-amino-5-hydroxy-2,7-napthalenedisulfonic acid
  • 4-14-00-02824 (Beilstein Handbook Reference)
  • kyselina1-amino-8-naftol-3,6-disulfonova
  • 1-hydroxy-8-amino-3,6-disulphonaphthalene
  • 8-Hydroxy-3,6-disulfo-1-naphthylamine
Show all 33 synonyms
  • naphthalene, 1-amino-8-hydroxy-3,6-disulpho-
  • 4-amino-5-hydroxynaphthalene-2,7-disulfonicacid
  • 1-hydroxy-8-aminonaphthalene-3,6-disulphonic acid
  • 5-amino-4-hydroxynaphthalene-2,7-disulfonic acid
  • 1-amino-8-hydroxy-naphthalene-3,6-disulphonic acid
  • 4-Amino-5-hydroxy-naphthalene-2,7-disulfonic acid, sodium salt
  • 4-Amino-5-hydroxy-naphthalene-2,7-disulfonic acidMonosodium salt
  • 4-Amino-5-hydroxy-2,7-naphthalenedisulfonic acid monosodium salt hydrate, 85%

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

Physical form
Powderexp.

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
319.32 g/molcalc.
Exact mass
318.982 Dacalc.
LogP (octanol/water)
0.62calc.
Topological polar surface area
155 Ųcalc.
Hydrogen bond donors
4calc.
Hydrogen bond acceptors
6calc.
Rotatable bonds
2calc.
Heavy atoms
20calc.
Rings
2calc.
Aromatic rings
2calc.
Fraction sp3 carbons
0calc.
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, c1ccc2ccccc2c1

c1ccc2ccccc2c1

2 rings, 10 atoms, the Naphthalene ring system.

17,920 other chemicals share this scaffold

Safety and hazards

GHS classification summary, not a safety data sheet

GHS signal word
Danger
GHS05: Corrosive
Corrosive
GHS07: Harmful or irritant
Harmful or irritant

Hazard statements

  • H302 + H332Harmful if swallowed. Harmful if inhaled.
  • H302Harmful if swallowed.
  • H314Causes severe skin burns and eye damage.
  • H315Causes skin irritation.
  • H319Causes serious eye irritation.
  • H332Harmful if inhaled.
  • H335May cause respiratory irritation.
Precautionary statements (26)
  • P260Do not breathe dust, fume, gas, mist, vapours or spray.
  • P261Avoid breathing dust, fume, gas, mist, vapours or spray.
  • P264Wash skin thoroughly after handling.
  • P264 + P265Wash skin thoroughly after handling. Do not touch eyes.
  • P270Do not eat, drink or smoke when using this product.
  • P271Use only outdoors or in a well-ventilated area.
  • P280Wear protective gloves, protective clothing, eye protection and face protection.
  • P301 + P317If swallowed: Get medical help.
  • P301 + P330 + P331If swallowed: Rinse mouth. Do not induce vomiting.
  • P302 + P352If on skin: Wash with plenty of water.
  • P302 + P361 + P354If on skin: Take off immediately all contaminated clothing. Immediately rinse with water for several minutes.
  • 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.
  • P305 + P354 + P338If in eyes: Immediately rinse with water for several minutes. Remove contact lenses, if present and easy to do. Continue rinsing.
  • P316Get emergency medical help immediately.
  • P317Get medical help.
  • P319Get medical help if you feel unwell.
  • P321Specific treatment (see supplemental first aid instructions on the label).
  • P330Rinse mouth.
  • 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.
  • P363Wash contaminated clothing 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

H acid suppliers

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

All 12 suppliers
12 of 12 offers

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

12 suppliers in 5 countries

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

H acid 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

Applications are not documented for this substance yet. Suppliers often describe uses on their product pages, linked in the suppliers list above.

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 H acid is traded under.

HS 2922.21Indicative HS code

Aminohydroxynaphthalenesulphonic acids and their salts

World exports in 2024
$112M
+9.6% vs 2023, imports $104M
2019 to 2024
Top exporters
  1. China81.7%
  2. India * partner reported13.6%
  3. Saudi Arabia2.8%
Top importers
  1. India * partner reported47.7%
  2. South Korea21.9%
  3. China5.9%

* Partner reported figures, a lower bound.

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

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

Frequently asked questions

Quick answers about H acid, based on the data on this page

What is H acid?

H acid is a chemical substance with the molecular formula C10H9NO7S2 and a molar mass of 319.32 g/mol. Its CAS registry number is 90-20-0. The IUPAC name is 4-amino-5-hydroxynaphthalene-2,7-disulfonic acid.

What is the CAS number of H acid?

The CAS registry number of H acid is 90-20-0. Other or deprecated CAS numbers: 5460-09-3, 90431-97-3, 90432-00-1.

What is the molecular formula and weight of H acid?

The molecular formula of H acid is C10H9NO7S2 and its molar mass is 319.32 g/mol.

Is H acid hazardous?

H acid carries the GHS signal word "Danger". Main hazards: harmful if swallowed. harmful if inhaled, harmful if swallowed, causes severe skin burns and eye damage. This summary is not an SDS, always read the supplier safety data sheet.

What is the HS code of H acid?

H acid is usually classified under HS code 292221 (Aminohydroxynaphthalenesulphonic acids and their salts). This is indicative, confirm it with your customs broker before shipping.

Where can I buy H acid?

CompoundList lists 12 suppliers of H acid in India, China, United States, Hong Kong and 1 more. Send one free request to get and compare quotes. Your contact details stay private until you accept a quote.

Where can I buy H acid in India?

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

What is the price of H acid?

Suppliers quote H acid 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 H acid

Get quotes for H acid

Post one free request with your grade, quantity and destination. Matching suppliers send quotes you can compare side by side.
Post a request Sell H acid
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 H acid 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/h-acid-90-20-0" title="H acid 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 Dye intermediates or HS code 292221

12 suppliers
Free quotes, contact stays private
Get quotes