My colleague David Fialho and I have published alongside our PI, Nick Hud, a review describing the potential prebiotic formation of noncanonical nucleosides. To summarize" >Noncanonical nucleosides could have predated the traditional "RNA World" in chemical evolution, and their formation could have occurred in a variety of ways. Importantly, divalent nucleosides are much more likely to react with sugars in chemical contexts that preclude hydroxide as a nucleofuge. Check out the paper if you want to learn more: **[Prebiotic Synthesis of Noncanonical Nucleosides and Nucleotides.](https://pubs.acs.org/doi/abs/10.1021/acs.chemrev.0c00069)**