2RMQ:
reference: Unexpected A-form formation of 4'-thioDNA in solution, revealed by NMR, and the implications as to the mechanism of nuclease resistance., Matsugami A, Ohyama T, Inada M, Inoue N, Minakawa N, Matsuda A, Katahira M, Nucleic Acids Res. 2008 Apr;36(6):1805-12. Epub 2008 Feb 5. PMID: 18252770

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