hydroxy acid

chemical compound

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June 29, 2026

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A hydroxy acid is a type of organic compound that contains both a hydroxyl group (-OH) and a carboxyl group (-COOH) within the same molecule. These compounds are generally weaker acids than mineral acids but stronger than alcohols.123

Hydroxy acids are widely found in nature and play roles in biological processes. For example, lactic acid, a simple hydroxy acid, is produced in muscle tissue during strenuous exercise and is also found in sour milk. Glycolic acid and lactic acid can be used to create polyesters for absorbable surgical sutures.4

When heated, hydroxy acids can undergo reactions to form cyclic esters called lactides or lactones.4

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carboxylic acid
Hydroxy and keto acids
The 2-, 3-, 4-, and 5-hydroxycarboxylic acids all lose water upon heating, although the products are not the same. The 2-hydroxy acids form cyclic dimeric esters (formed by the esterification of two molecules of the acid) called lactides, whereas the 3-…
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The 2-, 3-, 4-, and 5-hydroxycarboxylic acids all lose water upon heating, although the products are not the same. The 2-hydroxy acids form cyclic dimeric esters (formed by the esterification of two molecules of the acid) called lactides, whereas the 3-…
Read More