What Is Anthranilic Acid?
Anthranilic acid is an organic compound with the chemical formula C7H7NO2. It is also known as 2-aminobenzoic acid, carboxyaniline, 1-amino-2-carboxybenzene, among other names. Its CAS registration number is 118-92-3.
It has a molecular weight of 137.13, a melting point of 146-148 °C, and a boiling point of 200 °C. Anthranilic acid appears as a white or pale yellow crystalline powder at room temperature. It is odorless but has a sweet taste. Its density is 1.412 g/mL, and it has acid dissociation constants pKa of 2.17 (amino group) and 4.85 (carboxyl group).
Anthranilic acid is soluble in hot water, ethanol, and ether.
Uses of Anthranilic Acid
Anthranilic acid forms insoluble chelates with metal ions such as cadmium and cobalt. It is used in the determination of these metal ions and as a synthetic intermediate in dye and pigment synthesis, including indigo. For example, the diazo coupling reaction with dimethylaniline enables the synthesis of methyl red, an azo dye.
Derivatives of anthranilic acid are used in various applications. For instance, its ester compound with methanol is used as a flavoring agent.
Calcium anthranilic acid is used industrially as a raw material for acridine production.
Properties of Anthranilic Acid
Anthranilic acid undergoes various chemical reactions. Methyl red can be prepared from it by diazotization followed by a reaction with dimethylaniline.
It can also react with ethyl chloroformate or undergo a reaction with sodium anthranilate and phosgene to produce isatoic anhydride.
Types of Anthranilic Acid
Anthranilic acid is available for research and development purposes in various volumes such as 25g, 100g, and 500g. It is sold as a reagent that can be stored at room temperature.
Other Information on Anthranilic Acid
1. Synthesis of Anthranilic Acid
In industrial and synthetic chemistry, anthranilic acid is synthesized through the Hoffman rearrangement of phthalimides with hypochlorous acid, or by reducing o-nitrobenzoic acid.
2. Biosynthesis and Bioavailability of Anthranilic Acid
Known as vitamin L1 for its lactogenic effect on mammals, anthranilic acid is synthesized in vivo from chorismic acid and glutamine by anthranilic acid synthase in the shikimic acid pathway. It is also biosynthesized from kynurenine in the kynurenine pathway, a metabolic pathway of tryptophan. Anthranilic acid is a precursor to various alkaloids. Methyl anthranilate, an ester of anthranilic acid and methanol, is an aroma component found in grapes and jasmine.