Indole-5-carboxylic acid
Indole-5-carboxylic acid (CAS: 1670-81-1), a vital heterocyclic building block with the molecular formula C9H7NO2 and a molecular weight of 161.16 g/mol, is supplied by TSS with an assay of 99%. This compound serves as a key intermediate in diverse chemical syntheses, particularly in the preparation of biologically active molecules. Its utility spans the development of potential anticancer agents, immunomodulators, and antagonists for various physiological pathways, making it an important reagent for research and development in medicinal chemistry.
- IUPAC
- 5-Carboxyindole
- Synonyms
- 5-Carboxyindole

Preparation of Anticancer Immunomodulators
Indole-5-carboxylic acid is utilised as a reactant in synthesising pyridyl-ethenyl-indole derivatives. These compounds are investigated for their potential as anticancer immunomodulators, targeting tryptophan dioxygenase.
Synthesis of Indolyl-Quinolines
This indole derivative serves as a reactant for the metal- and solvent-free autoxidative coupling reaction to prepare indolyl-quinoline structures.
Formation of Anthranilic Acids
It acts as a reactant in the synthesis of anthranilic acids, employing bromamine-B as an oxidant in the presence of a palladium chloride catalyst.
Development of Indirubin Analogues
Indole-5-carboxylic acid is a key reactant in the synthetic routes leading to various indirubin derivatives, which are of interest in medicinal chemistry research.
Inhibitors of Gli1-Mediated Transcription
The compound is used to prepare amide conjugates with ketoprofen. These conjugates are explored for their inhibitory effects on Gli1-mediated transcription within the Hedgehog pathway.
Human Growth Hormone Secretagogue Receptor Antagonists
It serves as a reactant for synthesising piperazine-bisamide analogues designed as antagonists for the human growth hormone secretagogue receptor, with potential applications in obesity treatment.
| Molecular weight | 161.16 |
|---|---|
| Empirical formula | C9H7NO2 |
| Assay | 99% |
| Application | • Reactant for preparation of tryptophan dioxygenase inhibitors pyridyl-ethenyl-indoles, as potential anticancer immunomodulators1• Reactant for preparation of indolyl-quinolines via metal- and solvent-free autoxidative coupling reaction2• Reactant for preparation of anthranilic acids using bromamine-B oxidant and palladium chloride catalyst3• Reactant for synthesis of indirubin derivatives4• Reactant for preparation of amide conjugates with ketoprofen, as inhibitors of Gli1-mediated transcription in Hedgehog pathway5• Reactant for preparation of piperazine-bisamide analogs as human growth hormone secretagogue receptor antagonists for treatment of obesity6 |
| Melting point | 211-213 °C(lit.) |
| Protective equipment | Eyeshields, Gloves, type N95 (US), type P1 (EN143) respirator filter |
|---|---|
| Water hazard class (WGK, DE) | 3 |
Hazard information is provided for guidance. Always consult the product Safety Data Sheet (SDS), available on request, before handling.
Documentation
Every batch ships with a Certificate of Analysis covering assay, identity and purity; the grade is confirmed against your enquiry. Safety Data Sheets and technical data sheets are available on request.
Supply & logistics
Samples for technical evaluation; bulk MOQ by grade and packaging. In-stock material ships in 7–10 working days, worldwide, with full export documentation.
What is Indole-5-carboxylic acid used for?
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Indole-5-carboxylic acid is used as a reactant in the synthesis of various biologically active compounds, including potential anticancer agents, immunomodulators, indolyl-quinolines, anthranilic acids, and inhibitors of specific biological pathways like the Hedgehog pathway. It is also used in the preparation of human growth hormone secretagogue receptor antagonists.
What is the CAS number and molecular formula for Indole-5-carboxylic acid?
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The CAS number for Indole-5-carboxylic acid is 1670-81-1, and its molecular formula is C9H7NO2.
What grade and purity does Tech Serve Solutions supply?
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Tech Serve Solutions supplies Indole-5-carboxylic acid with an assay of 99%. This product is intended for chemical synthesis and research purposes. TSS does not represent it as USP, BP, EP, or any pharmacopoeia grade.
What are the safety and handling considerations for Indole-5-carboxylic acid?
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Indole-5-carboxylic acid requires careful handling. Personal protective equipment such as eyeshields and gloves should be worn. A respirator filter of type N95 (US) or P1 (EN143) is recommended. It is classified under WGK Germany 3, indicating a high hazard to water.
Is Indole-5-carboxylic acid packed, shipped, or exported by TSS?
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Yes, Tech Serve Solutions is a global supplier and exporter of fine chemicals, including Indole-5-carboxylic acid, and can handle domestic and international shipments.
How can I request a sample or a quote for Indole-5-carboxylic acid?
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To request a sample or a quote for Indole-5-carboxylic acid, please contact the TSS sales department via the website or direct inquiry channels.
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