227D:
reference: A crystallographic and spectroscopic study of the complex between d(CGCGAATTCGCG)2 and 2,5-bis(4-guanylphenyl)furan, an analogue of berenil. Structural origins of enhanced DNA-binding affinity., Laughton CA, Tanious F, Nunn CM, Boykin DW, Wilson WD, Neidle S, Biochemistry 1996 May 7;35(18):5655-61. PMID: 8639524

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