*** Welcome to piglix ***

Thiamin diphosphate

Thiamine pyrophosphate
Thiamine diphosphate.png
Names
IUPAC name
2-[3-[(4-amino-2-methylpyrimidin-5-yl)methyl]-4-methyl-1,3-thiazol-3-ium-5-yl]ethyl phosphono hydrogen phosphate
Other names
Thiamine diphosphate
Identifiers
3D model (JSmol)
ChemSpider
ECHA InfoCard 100.005.307
MeSH Thiamine+pyrophosphate
PubChem CID
UNII
Properties
C12H19N4O7P2S+
Molar mass 425.314382 g/mol
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa).
YesY  (what is YesYN ?)
Infobox references

Thiamine pyrophosphate (TPP or ThPP), or thiamine diphosphate (ThDP), or cocarboxylase is a thiamine (vitamin B1) derivative which is produced by the enzyme thiamine diphosphokinase. Thiamine pyrophosphate is a cofactor that is present in all living systems, in which it catalyzes several biochemical reactions.

Thiamine pyrophosphate is synthesized in the cytosol and is required in the cytosol for the activity of transketolase and in the mitochondria for the activity of pyruvate-, oxoglutarate- and branched chain keto acid dehydrogenases. To date, the yeast ThPP carrier (Tpc1p) the human Tpc and the Drosophila melanogaster have been identified as being responsible for the mitochondrial transport of ThPP and ThMP. 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.

TPP works as a coenzyme in many enzymatic reactions, such as:

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".


...
Wikipedia

...