L-Mannose is the isomer of D-Mannose which is a carbohydrate that is important in the glycosylation of molecules in a variety of cellular processes. It is involved in N and O glycosylation of bovine why protein products, used in infant formulas. It is also responsible for the O-glycosylation of the T helper cell-derived cytokine interlukin-17A, an important cell-signaling molecule. This is the labeled analog.