Английская Википедия:Gentisic acid

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Шаблон:Chembox Gentisic acid is a dihydroxybenzoic acid. It is a derivative of benzoic acid and a minor (1%) product of the metabolic break down of aspirin, excreted by the kidneys.[1]

It is also found in the African tree Alchornea cordifolia and in wine.[2]

Production

Gentisic acid is produced by carboxylation of hydroquinone.[3]

C6H4(OH)2 + CO2 → C6H3(CO2H)(OH)2

This conversion is an example of a Kolbe–Schmitt reaction.

Alternatively the compound can be synthesized from salicylic acid via Elbs persulfate oxidation.[4][5]

Reactions

In the presence of the enzyme gentisate 1,2-dioxygenase, gentisic acid reacts with oxygen to give maleylpyruvate:

2,5-dihydroxybenzoate + O2 <math>\rightleftharpoons</math> maleylpyruvate

Applications

As a hydroquinone, gentisic acid is readily oxidised and is used as an antioxidant excipient in some pharmaceutical preparations.

In the laboratory, it is used as a sample matrix in matrix-assisted laser desorption/ionization (MALDI) mass spectrometry,[6] and has been shown to conveniently detect peptides incorporating the boronic acid moiety by MALDI.[7]

References

Шаблон:Reflist

Cited sources

Шаблон:Phenolic acid

  1. Шаблон:Cite journal
  2. Шаблон:Cite journal
  3. Hudnall, Phillip M. (2005) "Hydroquinone" in Ullmann's Encyclopedia of Industrial Chemistry 2002, Wiley-VCH, Weinheim. Wiley-VCH, Weinheim. Шаблон:Doi.
  4. Шаблон:Cite book
  5. Шаблон:Cite journal
  6. Шаблон:Cite journal
  7. Шаблон:Cite journal