“They did not synthesise any of the four DNA bases, but presupposed them. Not surprising, since there is no good prebiotic route to cytosine especially, and the others are unstable. And how nice that they have used pure, uncontaminated reagents to make the sugars, instead of the diluted and grossly contaminated gunk that results from Miller–Urey-type experiments. We have long known about formose reaction (or Butlerov reaction, after eminent 19th-century Russian chemist Alexander Mikhaylovich Butlerov) to make sugars from simple aldehydes in alkaline conditions. But to get useful amounts, we must stop this reaction at just the right time, otherwise the Cannizzaro reaction and caramelization would destroy them.4”
Read more about this here: https://creation.com/dna-chemical-evolution
