Tautomerism

Amino acids are an important group of tautomeric molecules.

In chemistry, tautomerism is the ability of a molecule or other chemical species to change freely between several different shapes, called tautomers. It is a type of isomerism where the isomers can freely change into each other.^[1]

Tautomerism Media

The two tautomers of an amino acid: (1) neutral and (2) zwitterionic forms
Some examples of tautomers
Keto-enol tautomerization typically strongly favors the keto tautomer, but an important exception is the case of 1,3-diketones such as acetylacetone.
Glucose can exist in both a straight-chain and ring form.
Oxepin – benzene oxide equilibrium
2-pyridone-chemical-tautomer.svg

Sources

↑ International Union of Pure and Applied Chemistry. "tautomerism". Compendium of Chemical Terminology Internet edition.

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[1] International Union of Pure and Applied Chemistry. "tautomerism". Compendium of Chemical Terminology Internet edition.

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