Furnose

A furanose is a collective term for carbohydrates that have a chemical structure that includes a five-membered ring system consisting of four carbon atoms and one oxygen atom. The name derives from its similarity to the oxygen heterocycle furan, but the furanose ring does not have double bonds

A furanose extract from Panax quiquefolium (North American ginseng) was shown to decrease the incidence of acute respiratory illness and symptom duration in healthy adults.