Homogentisic acid
Structural formula | ||||||||||||||||||||||
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General | ||||||||||||||||||||||
Name | Homogentisic acid | |||||||||||||||||||||
Other names |
2,5-Dihydroxyphenylacetic acid |
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Sum formula | C8H8O4 | |||||||||||||||||||||
Brief description |
beige solid[1] |
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Features | ||||||||||||||||||||||
Molar mass | 168.15 g-mol-1 | |||||||||||||||||||||
State of aggregation |
synced and corrected by elderman — – for — |
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Melting point |
152-154 °C (monohydrate)[2] |
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Safety instructions | ||||||||||||||||||||||
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SI units are used wherever possible and customary. Unless otherwise stated, the data given are valid for standard conditions. |
Homogentisic acid is an intermediate product of the degradation of the amino acids phenylalanine and tyrosine and is present as an anion(homogentisate) at physiological pH values. It is converted into 4-maleylacetoacetic acid by the enzyme homogentisate dioxygenase (EC 1.13.11.5):
Subsequently, acetoacetic acid and fumaric acid are formed from this, which can be fed into the citrate cycle.[2]
In alkaptonuria, a metabolic disease, the enzyme is absent or not present in sufficient amounts. “Alkapton” is the oxidized, black-brown form of the homogentisate.
See also
- Metabolic disorder
Individual references
- ↑ a b c Data sheet Homogentisic acid at Sigma-Aldrich, retrieved April 4, 2011 (PDF).
- ↑ a b Entry for Homogentisic acid. In: Römpp Online. Georg Thieme Verlag, retrieved 16 June 2014
Categories
- Irritant substance
- Biochemical reaction
- Metabolic Intermediate
- Ethanoic acid
- Hydroquinone
- Benzyl compound