NMR studies on 4-thio-5-furan-modified and 4-thio-5-thiophene-modified nucleosides

• Published in: Magnetic resonance in chemistry 2016-11, Vol.54 (11), p.887-892
• Main Authors: Zhang, Xiao-Hui, Xu, Yao-Zhong
• Format: Article
• Language: English
• Subjects: 13C; 4-thiothymidine; 5-furan-4-thiouridine; 5-ringed nucleoside; 5-thiophene-4-thiouridine; Antineoplastic Agents - chemistry; Carbohydrates - chemistry; Carbon; Crystallography; Crystallography, X-Ray; DNA; Furans; Furans - chemistry; Magnetic Resonance Spectroscopy; Models, Molecular; modified nucleoside; NMR; Nuclear magnetic resonance; Nucleosides; Nucleosides - chemistry; Nucleotides; Orientation; Thiophenes; Thiophenes - chemistry; X-ray; X-rays
• ISSN: 0749-1581; 1097-458X
• DOI: 10.1002/mrc.4501

Systematic NMR characterization of 4‐thio‐5‐furan‐pyrimidine nucleosides or 4‐thio‐5‐thiophene‐pyrimidine nucleosides (ribonucleosides and 2′‐deoxynucleosides) was performed. All proton and carbon signals of 4‐thio‐5‐thiophene‐ribouridine and related analogues were unambiguously assigned. The orientations of the base (4‐thiouridine or its deoxy analogue) relative to the ring (furan or thiophene) are explored by a NMR approach and further supported by X‐ray crystallographic studies. The procedures presented here would be applicable to other modified nucleosides and nucleotides. Copyright © 2016 John Wiley & Sons, Ltd. 1H and 13C NMR were used to characterize 4‐thio‐5‐furan nucleosides and 4‐thio‐5‐thiophene nucleosides and to study the orientations of the base (4‐thiouracil) relative to the ring (furan or thiophene). The protocols can be applied to other modified nucleosides and nucleotides.