7-Iodo-5-aza-7-deazaguanine ribonucleoside: crystal structure, physical properties, base-pair stability and functionalization.

ABSTRACT: The positional change of nitrogen-7 of the RNA constituent guanosine to the bridgehead position-5 leads to the base-modified nucleoside 5-aza-7-deazaguanosine. Contrary to guanosine, this molecule cannot form Hoogsteen base pairs and the Watson-Crick proton donor site N3-H becomes a proton-acceptor site. This causes changes in nucleobase recognition in nucleic acids and has been used to construct stable `all-purine' DNA and DNA with silver-mediated base pairs. The present work reports the single-crystal X-ray structure of 7-iodo-5-aza-7-deazaguanosine, C₁₀H₁₂IN₅O₅ (1). The iodinated nucleoside shows an anti conformation at the glycosylic bond and an N conformation (O4'-endo) for the ribose moiety, with an antiperiplanar orientation of the 5'-hydr

SUBMITTER: Kondhare D 

PROVIDER: S-EPMC7199197 | biostudies-literature | 2020 May

REPOSITORIES: biostudies-literature