Possible prebiotic synthesis of monosaccharides from formaldehyde in presence of phosphates

Condensation of formaldehyde and lower carbohydrates (glycolaldehyde, glyceraldehyde, and dihydroxyacetone) is effectively catalyzed by heterogeneous and homogeneous phosphates in neutral aqueous medium. The interaction of formaldehyde and dihydroxyacetone leads to the preferential formation of 3-pentulose and erythrulose with yields of 40% and 45%, respectively. In absence of formaldehyde, the condensation of glycolaldehyde and glyceraldehyde catalyzed by phosphates leads to the formation of ribose and fructose. We demonstrate the possibility of formation of higher monosaccharides from pure formaldehyde in the course of the combined photochemical and phosphate-catalyzed reactions in plausible prebiotic conditions.