3NP6:
reference: X-Ray diffraction analyses of the natural isoquinoline alkaloids Berberine and Sanguinarine complexed with double helix DNA d(CGTACG)., Ferraroni M, Bazzicalupi C, Bilia AR, Gratteri P, Chem Commun (Camb). 2011 May 7;47(17):4917-9. Epub 2011 Mar 22. PMID: 21431128

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