Exploratory studies to investigate linked prebiotic origin of RNA and coded peptides - 2nd communication - Derivation and reactivity of xylose phosphates

The potentially prebiotic synthesis of ribo-nucleotides by stepwise pyrimidine nucleobase assembly on arabinose-3-phosphate derivatives has been demonstrated in previous work [1]. Consideration of the provenance of pentose phosphates, by aldolisation or sugar phosphorylation, suggested that 2-phosphate derivatives might be generated more easily than 3-phosphate derivatives. In the 2-phosphate series, nucleobase-assembly chemistry to give ribo-nucleotides/nucleic acid can be envisaged from xylo-configured starting materials. In this paper, the derivation of xylose-2-phosphate derivatives by aldol chemistry and attempts to demonstrate subsequent pyrimidine nucleobase assembly are reported.