Biochemistry - The Chemical Reactions of Living Cells, Volume 2 - D. Metzler 1980

Coenzymes - specialized natural reagents
Lipoic acid and the oxidative decarboxylation of α-keto acids
Chemical reactions involving lipoic acid

The most notable chemical feature of Lipoic Acid is the ring strain (~17–25 kJ∙mol-1) present in its cyclic disulfide. As a result, thiol groups and cyanide ions readily react with oxidized lipoic acid to form mixed disulfides

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and isothiocyanates

Another consequence of the ring strain is that the reduction potential E0' (pH 7, 25°C) is —0.30 V, which is very close to the corresponding value for reduced NAD+ (—0.32 V). Thus, the reoxidation of the reduced lipoic acid amide by NAD+ is thermodynamically feasible [137]. Yet another property stemming from the ring strain in lipoic acid is the presence of an absorption maximum at 333 nm.



Last update: 06/08/2026

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