Abstract
The present invention relates to the use of sodium dithionite to reduce at least one aldehyde or ketone function of a carbohydrate, C-glycoside, oligosaccharide, or water-soluble polysaccharide in the absence of a water-immiscible organic solvent and in the absence of a phase transfer agent. The invention also relates to a preparation method that includes treating a carbohydrate, a C-glycoside, an oligosaccharide, or a water-soluble polysaccharide with sodium dithionite.