3OPI:
reference: Altering the Electrostatic Potential in the Major Groove: Thermodynamic and Structural Characterization of 7-Deaza-2'-deoxyadenosine:dT Base Pairing in DNA., Kowal EA, Ganguly M, Pallan PS, Marky LA, Gold B, Egli M, Stone MP, J Phys Chem B. 2011 Dec 1;115(47):13925-34. Epub 2011 Nov 8. PMID: 22059929

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