Ribonucleoside analogs bearing terminal alkynes, including 7-ethynyl-8-aza-7-deazaadenosine (7-EAA), are useful for RNA modification applications. However, while alkyne- and triazole-bearing ribonucleosides are in wide spread use, very little information is available on the impact of these modifications on RNA structure. By solving crystal structures for RNA duplexes containing these analogs, we show that, like adenosine, 7-EAA and a triazole derived from 7-EAA base pair with uridine and are well accommodated within an A-form helix. We show copper-catalyzed azide/alkyne cycloaddition (CuAAC) reactions with 7-EAA are sensitive to the RNA secondary structure context with single stranded sites reacting faster than duplex sites. 7-EAA and its triazole products are recognized in RNA template strands as adenosine by avian myoblastosis virus reverse transcriptase (AMV-RT). In addition, 7-EAA in RNA is a substrate for an active site mutant of the RNA editing adenosine deaminase ADAR2. These studies extend our understanding of the impact of these novel nucleobase analogs and set the stage for their use in probing RNA structure and metabolism.