D-Fructose-1,6-bisphosphate (FBP), a common metabolic sugar, is the precursor of glyceraldehyde 3-phosphate and dihydroxyacetone phosphate in the glycolytic pathway. It is an allosteric activator of enzymes such as pyruvate kinase and a substrate used to identify and characterize enzymes such as fructose-1,6-bisphosphate aldolase(s) and fructose-1, 6-bisphosphatase(s). FBP is studied as a neuroprotective agent in brain injury.