233D:
reference: The crystal structure analysis of d(CGCGAASSCGCG)2, a synthetic DNA dodecamer duplex containing four 4'-thio-2'-deoxythymidine nucleotides., Boggon TJ, Hancox EL, McAuley-Hecht KE, Connolly BA, Hunter WN, Brown T, Walker RT, Leonard GA, Nucleic Acids Res 1996 Mar 1;24(5):951-61. PMID: 8600465

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