Retracted Article: Divergent synthesis of 5-substituted pyrimidine 2′-deoxynucleosides and their incorporation into oligodeoxynucleotides for the survey of uracil DNA glycosylases
Authors: Dawanna S White
Alyson M Curry
Ai Tran
Yana Cen
Song Zheng
Journal: Chemical Science (2020)
Discipline: CHEMISTRY
Keywords: 5-methylcytosine; oxidative DNA damage; epigenetic markers; chromatin function; disease pathology
Affiliations: Department of Pharmaceutical Sciences, Albany College of Pharmacy and Health Sciences, Colchester, USA, Department of Medicinal Chemistry, Virginia Commonwealth University, Richmond, Institute for Structural Biology

Abstract:  Recent studies have indicated that 5-methylcytosine (5mC) residues in DNA can be oxidized and potentially deaminated to the corresponding thymine analogs. Some of these oxidative DNA damages have been implicated as new epigenetic markers that could have profound influences on chromatin function as well as disease pathology. In response to oxidative damage, the cells have a complex network of repair systems that recognize, remove and rebuild the lesions. However, how the modified nucleobases are detected and repaired remains elusive, largely due to the limited availability of synthetic oligodeoxynucleotides (ODNs) containing these novel DNA modifications. A concise and divergent synthetic strategy to 5mC derivatives has been developed. These derivatives were further elaborated to the corresponding phosphoramidites to enable the site-specific incorporation of modified nucleobases into ODNs using standard solid-phase DNA synthesis. The synthetic methodology, along with the panel of ODNs, is of great value to investigate the biological functions of epigenetically important nucleobases, and to elucidate the diversity in chemical lesion repair. 

Retracted: Yes

PubPeer comments:
 Copy pasted from https: pubs.rsc.org doi d1sc90028e :  Retraction of u2018Divergent synthesis of 5-substituted pyrimidine 2u2032-deoxynucleosides and their incorporation into oligodeoxynucleotides for the survey of uracil DNA glycosylasesu2019 by Ai Tran et al., Chem. Sci., 2020, 11, 11818u201311826, DOI: 10.1039 D0SC04161K The Royal Society of Chemistry hereby wholly retracts this Chemical Science article due to concerns about the reproducibility of the data. The Royal Society of Chemistry has been contacted by the authors of this article to alert us that recent experiments by their group have shown that some results are not reproducible, especially the yields of several key intermediates. Given the focus on the easy access to epigenetically important nucleosides and related ODNs, unreliable yields significantly impact the confidence in the results. In addition, it was discovered that one of the biological samples provided to the authors was mislabelled. The human stem cells were actually mouse stem cells, hence some discussion and conclusions in the article may no longer apply. Ahead of a thorough re-examination of the entire study, in order to preserve the rigor of the scientific record, the signing authors have chosen to retract the article and they would like to apologise for any inconvenience this may have caused for readers. Signed: Ai Tran, Song Zheng, Dawanna S. White, Alyson M. Curry and Yana Cen. Retraction endorsed by May Copsey, Executive Editor, Chemical Science. First published, 25 Feb 2021. See https: retractionwatch.com 2021 03 10 drug-researchers-retract-two-papers-one-because-human-stem-cells-were-actually-mouse-stem-cells for backgrounds. ,