2GYX:
reference: Induced fit conformational changes of a "reversed amidine" heterocycle: optimized interactions in a DNA minor groove complex., Munde M, Lee M, Neidle S, Arafa R, Boykin DW, Liu Y, Bailly C, Wilson WD, J Am Chem Soc. 2007 May 2;129(17):5688-98. Epub 2007 Apr 11. PMID: 17425312

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