8-Azanebularine, a chemical compound substituting hydrogen for the C6 amino group, effectively inhibits the ADAR2 reaction at elevated concentrations (IC50=15 mM), and exhibits high-affinity binding (KD=2 nM) when incorporated into an RNA structure recognized by human ADAR2. This characteristic makes 8-Azanebularine valuable for researching the ADAR-catalyzed RNA-editing reaction.