Cas no 81-16-3 (Tobias acid)

Tobias acid, chemically known as 2-amino-1-naphthalenesulfonic acid, is a naphthalene derivative widely used as an intermediate in the synthesis of dyes and pigments. Its sulfonic acid and amino functional groups make it a versatile building block for azo dyes, particularly in producing vibrant and lightfast colors. The compound exhibits good solubility in water and alkaline solutions, facilitating its incorporation into dye formulations. Its consistent purity and reactivity ensure reliable performance in industrial applications. Tobias acid is valued for its role in creating high-performance dyes for textiles, inks, and other specialty chemicals, contributing to efficient and scalable production processes.
Tobias acid structure
Tobias acid structure
Product Name:Tobias acid
CAS No:81-16-3
MF:C10H9NO3S
MW:223.248361349106
MDL:MFCD00003988
CID:34239
PubChem ID:24857514
Update Time:2026-05-18

Tobias acid Chemical and Physical Properties

Names and Identifiers

    • 2-Aminonaphthalene-1-sulfonic acid
    • 2-Amino-1-naphthalenesulfonic acid
    • 2-aminonaphthalene-1-sulphonic acid
    • 2-Naphthylamine-1-sulfonic acid
    • Naphthol Green B
    • Tobias Acid
    • 吐氏酸
    • 2-Naphthylamino,1-sulfonic acid
    • AC-10810
    • 2-AMINO-1-NAPHTHALENESULFONIC ACID [HSDB]
    • 2-aminonaphthalen-1-sulfonsyre
    • AMINO-1-NAPHTHALENESULFONIC ACID, 2-
    • EINECS 201-331-5
    • STL426807
    • F71314
    • Amino-1-naphthalenesulfonic acid
    • Tox21_200507
    • EN300-6491456
    • 81-16-3
    • 2-Naphthylamine-1-sulfonicacid
    • CAS-81-16-3
    • BRN 0613084
    • 2-Amino-naphthalenesulfonic acid
    • BBL034632
    • NCIOpen2_002342
    • Kyselina tobiasova
    • HSDB 5239
    • Naphthylamine sulfonic acid (2, 1-)
    • 1-Naphthalenesulfonic acid, 2-amino-
    • 2-Amino-1-naphthalenesulfonic acid, 98%
    • VS-12623
    • Tobias acid;2-Naphthylamine-1-sulfonic acid
    • NSC5523
    • W-104215
    • Q11751621
    • F9QKW1FCE0
    • 4-14-00-02792 (Beilstein Handbook Reference)
    • 2-Aminonaphthalene-1-sulfonicacid
    • CHEMBL3182507
    • 2-amino-naphthalene-1-sulphonic acid
    • aminonaphthalenesulfonic acid
    • Kyselina 2-naftylamin-1-sulfonova
    • DTXSID7020922
    • InChI=1/C10H9NO3S/c11-9-6-5-7-3-1-2-4-8(7)10(9)15(12,13)14/h1-6H,11H2,(H,12,13,14
    • NSC-5523
    • 1-Aminonaphthaline-3-sulfonic acid
    • A0343
    • Kyselina tobiasova [Czech]
    • DTXCID90922
    • WLN: L66J BSWQ CZ
    • NCGC00258061-01
    • UNII-F9QKW1FCE0
    • NSC 5523
    • Kyselina 2-naftylamin-1-sulfonova [Czech]
    • Naphthylaminsulfosaure
    • AKOS015900596
    • LS-7538
    • FT-0611011
    • SCHEMBL313224
    • NCGC00248665-01
    • 2-NAPHTHYLAMINE-1-SULFONIC ACID [MI]
    • RKL10014
    • MFCD00003988
    • Naphthylamine sulfonic acid (2,1-)
    • CCRIS 9048
    • NS00038109
    • 2-Amino-1-naphthalenesulfonic acid (ACI)
    • 1-Sulfo-2-naphthylamine
    • 2-Aminonaphthalenesulfonic acid
    • 2-Aminonaphthalene-1-sulphonicacid
    • Tobias acid
    • MDL: MFCD00003988
    • Inchi: 1S/C10H9NO3S/c11-9-6-5-7-3-1-2-4-8(7)10(9)15(12,13)14/h1-6H,11H2,(H,12,13,14)
    • InChI Key: GWIAAIUASRVOIA-UHFFFAOYSA-N
    • SMILES: O=S(C1C2C(=CC=CC=2)C=CC=1N)(O)=O
    • BRN: 613084

Computed Properties

  • Exact Mass: 223.03000
  • Monoisotopic Mass: 223.030314
  • Isotope Atom Count: 0
  • Hydrogen Bond Donor Count: 2
  • Hydrogen Bond Acceptor Count: 4
  • Heavy Atom Count: 15
  • Rotatable Bond Count: 1
  • Complexity: 322
  • Covalently-Bonded Unit Count: 1
  • Defined Atom Stereocenter Count: 0
  • Undefined Atom Stereocenter Count : 0
  • Defined Bond Stereocenter Count: 0
  • Undefined Bond Stereocenter Count: 0
  • Surface Charge: 0
  • XLogP3: 1.8
  • Topological Polar Surface Area: 80.4

Experimental Properties

  • Color/Form: White acicular crystals
  • Density: 1.3588 (rough estimate)
  • Melting Point: 180 °C
  • Boiling Point: 220°C (rough estimate)
  • Refractive Index: 1.5250 (estimate)
  • PSA: 88.77000
  • LogP: 3.33070
  • Merck: 6406
  • Solubility: Soluble in hot water, slightly soluble in cold water, very slightly soluble in ethanol and ether.

Tobias acid Security Information

  • Prompt:warning
  • Signal Word:Warning
  • Hazard Statement: H320
  • Warning Statement: P264-P305+P351+P338+P337+P313
  • Hazardous Material transportation number:2585
  • WGK Germany:1
  • Hazard Category Code: 36/37/38-40
  • Safety Instruction: S26-S36/37/39
  • RTECS:QK1250000
  • Safety Term:8
  • Packing Group:III
  • Risk Phrases:R36/37/38; R40
  • HazardClass:8
  • PackingGroup:III
  • TSCA:Yes
  • Storage Condition:Warehouse ventilation and low temperature drying

Tobias acid Customs Data

  • Customs Data:

    China Customs Code:

    2921450090

    Overview:

    2921450090. 1-Naphthylamine and2-Derivatives and salts of naphthylamine(include1-Naphthylamine). VAT:17.0%. Tax refund rate:9.0%. Regulatory conditions:nothing. MFN tariff:6.5%. general tariff:30.0%

    Declaration elements:

    Product Name, component content, use to

    Summary:

    2921450090 1-naphthylamine (Ah-naphthylamine), 2-naphthylamine (b-naphthylamine) and their derivatives; salts thereof.Supervision conditions:None.VAT:17.0%.Tax rebate rate:9.0%.MFN tariff:6.5%.General tariff:30.0%

Tobias acid Pricemore >>

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Tobias acid Production Method

Production Method 1

Reaction Conditions
1.1 Reagents: Sodium hydroxide Solvents: Water
1.2 -
Reference
Arylene azo 1,5-dihydroxy naphthalene-formaldehyde oligomeric dyes
Patel, H. S.; et al, International Journal of Polymeric Materials, 2001, 49(4), 457-465

Production Method 2

Reaction Conditions
1.1 Reagents: Potassium carbonate
2.1 Reagents: Sodium hydroxide Solvents: Water
2.2 -
Reference
Arylene azo 1,5-dihydroxy naphthalene-formaldehyde oligomeric dyes
Patel, H. S.; et al, International Journal of Polymeric Materials, 2001, 49(4), 457-465

Tobias acid Raw materials

Tobias acid Preparation Products

Tobias acid Suppliers

Tiancheng Chemical (Jiangsu) Co., Ltd
Gold Member
Audited Supplier Audited Supplier
(CAS:81-16-3)2-Amino-1-naphthalenesulfonic Acid, ≥ 98.0%
Order Number:LE14229;LE6076
Stock Status:in Stock
Quantity:25KG,200KG,1000KG
Purity:99%
Pricing Information Last Updated:Friday, 20 June 2025 12:10
Price ($):discuss personally

Tobias acid Spectrogram

GC-MS
GC-MS
1H NMR 300 MHz DMSO
1H NMR
13C NMR
13C NMR

Additional information on Tobias acid

Introduction to Tobias Acid (CAS No. 81-16-3)

Tobias acid, chemically known as 2-[(2-hydroxy-5-methylphenyl)amino]benzoic acid, is a compound with the CAS number 81-16-3. This compound has garnered significant attention in the field of chemical and pharmaceutical research due to its unique structural properties and potential applications. The molecular formula of Tobias acid is C9H9NO3, and it is characterized by the presence of an amino group and a hydroxyl group on a benzene ring, which contribute to its reactivity and functionality.

The synthesis of Tobias acid involves a series of well-defined chemical reactions that highlight its versatility as a building block in organic chemistry. The process typically begins with the condensation of aniline derivatives with salicylic acid or its derivatives, followed by further functionalization to introduce the necessary substituents. This synthetic route underscores the importance of Tobias acid in the preparation of more complex molecules, particularly in the pharmaceutical industry.

In recent years, Tobias acid has been extensively studied for its potential applications in drug development. Its structural features make it a valuable intermediate in the synthesis of various bioactive compounds. For instance, researchers have explored its use in the development of novel anti-inflammatory agents, where the hydroxyl and amino groups can be strategically modified to enhance binding affinity to target enzymes and receptors.

One of the most compelling aspects of Tobias acid is its role in medicinal chemistry. The compound's ability to act as a precursor for more complex pharmacophores has led to several promising developments. A notable example is its application in the synthesis of kinase inhibitors, which are crucial in treating various types of cancer. The precise arrangement of functional groups in Tobias acid allows for fine-tuning of molecular properties, making it an ideal candidate for designing drugs with high specificity and efficacy.

The pharmacological profile of Tobias acid has been further elucidated through computational studies and experimental investigations. These studies have revealed that the compound exhibits significant inhibitory activity against certain enzymes involved in inflammatory pathways. This finding has opened up new avenues for therapeutic intervention, particularly in chronic inflammatory diseases where traditional treatments may fall short.

Moreover, Tobias acid has shown promise in the field of material science. Its ability to form stable complexes with metal ions has led to the development of novel materials with applications ranging from catalysis to sensors. The interaction between Tobias acid and transition metals can be tailored to achieve specific functionalities, making it a versatile tool for material design.

The latest research on Tobias acid also highlights its potential in environmental science. Studies have demonstrated that derivatives of this compound can effectively degrade environmental pollutants through photochemical processes. This application is particularly relevant in the context of emerging contaminants that pose significant challenges to water treatment systems.

In conclusion, Tobias acid (CAS No. 81-16-3) is a multifaceted compound with broad applications across multiple scientific disciplines. Its unique structural features and reactivity make it a valuable tool in pharmaceutical research, material science, and environmental chemistry. As our understanding of its properties continues to grow, so too will its impact on advancing scientific knowledge and technological innovation.

Recommended suppliers
Tiancheng Chemical (Jiangsu) Co., Ltd
(CAS:81-16-3)2-Amino-1-naphthalenesulfonic Acid, ≥ 98.0%
LE14229;LE6076
Purity:99%/99%
Quantity:25KG,200KG,1000KG/25KG,200KG,1000KG
Price ($):Inquiry/Inquiry
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