Anthranilic acid

Anthranilic acid (o-aminobenzoic acid, 2-aminobenzoic acid, 2-AA, 2AA, AA) is an aromatic acid with the formula C6H4(NH2)(CO2H). The molecule consists of a benzene ring, ortho-substituted with a carboxylic acid and an amine. As a result of containing both acidic and basic functional groups, the compound is amphoteric. Anthranilic acid is a white solid when pure, although commercial samples may appear yellow. It is sometimes referred to as vitamin L1 and has a sweetish taste. The anion −, obtained by the deprotonation of anthranilic acid, is called anthranilate. Anthranilic acid (o-aminobenzoic acid, 2-aminobenzoic acid, 2-AA, 2AA, AA) is an aromatic acid with the formula C6H4(NH2)(CO2H). The molecule consists of a benzene ring, ortho-substituted with a carboxylic acid and an amine. As a result of containing both acidic and basic functional groups, the compound is amphoteric. Anthranilic acid is a white solid when pure, although commercial samples may appear yellow. It is sometimes referred to as vitamin L1 and has a sweetish taste. The anion −, obtained by the deprotonation of anthranilic acid, is called anthranilate. Although not usually referred to as such, it is an amino acid. Solid anthranilic acid consists of both the amino-carboxylic acid and the zwitterionic ammonium carboxylate forms. Many routes to anthranilic acid have been described. Industrially it is produced from phthalic anhydride, beginning with amination: The resulting sodium salt of phthalamic acid is decarbonylated via a Hofmann rearrangement of the amide group, induced by hypochlorite: A related method involves treating phthalimide with sodium hypobromite in aqueous sodium hydroxide, followed by neutralization. In the era when indigo dye was obtained from plants, it was degraded to give anthranilic acid. Anthranilic acid was first obtained by base-induced degradation of indigo. Anthranilic acid is biosynthesized from chorismic acid. It is the precursor to the amino acid tryptophan via the attachment of phosphoribosyl pyrophosphate to the amine group. Industrially, anthranilic acid is an intermediate in the production of azo dyes and saccharin. It and its esters are used in preparing perfumes to mimic jasmine and orange, pharmaceuticals (loop diuretics, such as furosemide) and UV-absorber as well as corrosion inhibitors for metals and mold inhibitors in soy sauce. Anthranilic acid can be used in organic synthesis to generate benzyne, which can undergo various reactions, including a rapid dimerizization to form biphenylene. It reacts with phosgene to give isatoic anhydride, a versatile reagent.