311D:
reference: Structure of a bis-amidinium derivative of hoechst 33258 complexed to dodecanucleotide d(CGCGAATTCGCG)2: the role of hydrogen bonding in minor groove drug-DNA recognition., Clark GR, Boykin DW, Czarny A, Neidle S, Nucleic Acids Res 1997 Apr 15;25(8):1510-5. PMID: 9162901

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