Anatomical Therapeutic Chemical Classification System
Thiamine pyrophosphate (TPP), the coenzymatic form of thiamine, is involved in two main types of metabolic reactions: decarboxylation of α-ketoacids (e.g. pyruvate, α-ketoglutarate and branched-chain keto acids) and transketolation (e.g. among hexose and pentose phosphates). Therefore, the principal physiological role of thiamine is as a coenzyme in carbohydrate metabolism, where TPP is required for several stages in the breakdown of glucose to provide energy.