A series of purine‐based spin labels was prepared for noncovalent spin‐labeling of abasic sites of duplex nucleic acids through hydrogen bonding to an orphan base on the opposing strand and π‐stacking interactions with the flanking bases. Both 1,1,3,3‐tetramethylisoindolin‐2‐yloxyl and 2,2,6,6‐tetramethylpiperidine‐1‐oxyl (TEMPO) were conjugated to either the C2‐ or C6‐position of the purines, yielding nitroxide derivatives of guanine, adenine, or 2,6‐diaminopurine. The isoindoline‐derived spin labels showed extensive or full binding to abasic sites in RNA duplexes, whereas the TEMPO‐derived spin labels showed limited binding. An adenine‐derived spin label (5) bound fully at low temperature to abasic sites in both DNA and RNA duplexes when paired with thymine and uracil, respectively, complementing the previously described guanine‐derived spin label Ǵ, which binds efficiently opposite cytosine. Compound Ǵ was also shown to bind to abasic sites in DNA–RNA hybrids, either in the DNA‐ or the RNA‐strand. Ǵ showed only a minor flanking‐sequence effect upon binding to abasic sites in RNA. When the abasic site was placed close to the end of the RNA duplex, the affinity of the spin label Ǵ was reduced; full binding was observed at the fourth position from the duplex end. In summary, spin labels 5 and Ǵ showed full binding to abasic sites in both DNA and RNA duplexes and are promising spin labels for structural studies of nucleic acids by pulsed EPR methods.
Chemistry - A European Journal – Wiley
Published: Jan 15, 2018
Keywords: ; ; ; ;
It’s your single place to instantly
discover and read the research
that matters to you.
Enjoy affordable access to
over 18 million articles from more than
15,000 peer-reviewed journals.
All for just $49/month
Query the DeepDyve database, plus search all of PubMed and Google Scholar seamlessly
Save any article or search result from DeepDyve, PubMed, and Google Scholar... all in one place.
Get unlimited, online access to over 18 million full-text articles from more than 15,000 scientific journals.
Read from thousands of the leading scholarly journals from SpringerNature, Elsevier, Wiley-Blackwell, Oxford University Press and more.
All the latest content is available, no embargo periods.
“Hi guys, I cannot tell you how much I love this resource. Incredible. I really believe you've hit the nail on the head with this site in regards to solving the research-purchase issue.”Daniel C.
“Whoa! It’s like Spotify but for academic articles.”@Phil_Robichaud
“I must say, @deepdyve is a fabulous solution to the independent researcher's problem of #access to #information.”@deepthiw
“My last article couldn't be possible without the platform @deepdyve that makes journal papers cheaper.”@JoseServera