Fig. 5 | Nature Communications

Fig. 5

From: Selective prebiotic conversion of pyrimidine and purine anhydronucleosides into Watson-Crick base-pairing arabino-furanosyl nucleosides in water

Fig. 5

Concomitant synthesis of four Watson–Crick base-pairing nucleosides. a One-pot reaction of an equimolar mixture of anhydroadenosine (3A), anhydroguanosine (3G) and anhydrocytidine (3C) with H2S (20 equiv., pH 7) in water, then H2O2 (20 equiv., pH 7) in water affords adenosine ara-4A (53%), guanosine ara-4G (62%), cytidine ara-4C (47%) and uridine ara-4U (35%). The isourea moieties (blue) of the anhydropurines (3A/G) and anhydropyrimidine (3C) were differentiated in situ to afford the canonical Watson–Crick base-pairing nucleobase moieties regiospecifically on a furanosyl-sugar scaffold, by reduction (orange) and hydrolysis (magenta), respectively. b 1H NMR spectrum (600 MHz, 9:1 H2O/D2O, 25 °C, δ = 5.5–7.0 ppm) showing the prebiotic synthesis of cytidine ara-4C, uridine ara-4U, adenosine ara-4A and guanosine ara-4G following the sequential addition of H2S and H2O2 to anhydrocytidine 3C, anhydroadenosine 3A and anhydroguanosine 3G in water. c 1H NMR spectrum (600 MHz, 9:1 H2O/D2O, 25 °C, δ = 5.5–7.0 ppm) of substrates anhydrocytidine 3C, anhydroadenosine 3A and anhydroguanosine 3G in water

Back to article page