Strands in a Web: Free Energies of Select Prebiotic Reactions with Sugars, Nitriles and Azoles

Using computational chemistry, we determined the free energy changes for the reactions of C2 and C3 sugars with HCN and NH2CN to form amino acids and azoles respectively. Amino acids and azoles may further react with the initial sugars to produce more complex molecules, adding to the complex web of prebiotic chemistry with its myriad species. For the reactions we have selected, our calculations provide a guide, albeit incomplete, of which pathways are thermodynamically and/or kinetically favorable and which species might be observed starting from just a handful of simple reactants. The reactions examined are strands in a web, connecting different sectors of prebiotic chemistry to the larger network of origins-of-life chemistry.