Which of the following compounds is NOT a glycolytic intermediate?

Fructose 2,6-bisphosphate is not a glycolytic intermediate but rather an important regulator of glycolysis and gluconeogenesis. It is formed from fructose 6-phosphate and ATP by the enzyme phosphofructokinase-2 (PFK-2). Instead of being a direct participant in the reactions of glycolysis, it plays a significant role in regulating the activity of key enzymes like phosphofructokinase-1 (PFK-1), which is the main control point in the glycolytic pathway.

In contrast, fructose 1,6-bisphosphate, glyceraldehyde 3-phosphate, and phosphoenolpyruvate are all direct intermediates in the glycolytic pathway. Fructose 1,6-bisphosphate is produced from fructose 6-phosphate and is then cleaved into glyceraldehyde 3-phosphate and dihydroxyacetone phosphate, while phosphoenolpyruvate is a key intermediate before pyruvate is formed at the end of glycolysis. Glyceraldehyde 3-phosphate is a crucial intermediate that participates in subsequent reactions leading to ATP production. Therefore, it is Fructose 2,