Thiamine pyrophosphate | |
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2-[3-[(4-amino-2-methylpyrimidin-5-yl)methyl]-4-methyl-1,3-thiazol-3-ium-5-yl]ethyl phosphono hydrogen phosphate |
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Other names
Thiamine diphosphate |
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Identifiers | |
CAS number | 154-87-0 |
PubChem | 1132 |
ChemSpider | 10670483 |
UNII | Q57971654Y |
MeSH | Thiamine+pyrophosphate |
Jmol-3D images | Image 1 |
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Properties | |
Molecular formula | C12H19N4O7P2S+ |
Molar mass | 425.314382 g/mol |
(verify) (what is: / ?) Except where noted otherwise, data are given for materials in their standard state (at 25 °C, 100 kPa) |
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Infobox references |
Thiamine pyrophosphate (TPP or ThPP), or thiamine diphosphate (ThDP), is a thiamine (vitamin B1) derivative which is produced by the enzyme thiamine pyrophosphatase. Thiamine pyrophosphate is a coenzyme that is present in all living systems, in which it catalyzes several biochemical reactions. It was first discovered as an essential nutrient (vitamin) in humans through its link with the peripheral nervous system disease Beriberi, which results from a deficiency of thiamine in the diet.[1]
TPP works as a coenzyme in many enzymatic reactions, such as:
Contents |
Chemically, TPP consists of a pyrimidine ring which is connected to a thiazole ring, which is in turn connected to a pyrophosphate (diphosphate) functional group.
The part of TPP molecule that is most commonly involved in reactions is the thiazole ring, which contains nitrogen and sulfur. Thus, the thiazole ring is the "reagent portion" of the molecule. The C2 of this ring is capable of acting as an acid by donating its proton and forming a carbanion. Normally, reactions that form carbanions are highly unfavorable, but the positive charge on the tetravalent nitrogen just adjacent to the carbanion stabilizes the negative charge, making the reaction more favorable. (A compound with positive and negative charges on adjacent atoms is called an ylid or ylide, so sometimes the carbanion form of TPP is referred to as the "ylid form".[1][3]
In several reactions, including that of pyruvate decarboxylase, alpha-ketoglutarate dehydrogenase, and transketolase, TPP catalyses the reversible cleavage of a substrate compound at a carbon-carbon bond connecting a carbonyl group to an adjacent reactive group (usually a carboxylic acid or an alcohol). It achieves this in four basic steps:
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