Molecular recognition of an adenine derivative by organoplatinum(II) complexes with hydrogen-bonding functionality.

Abstract The first examples of adenine binding by isomeric organoplatinum(II) complexes bearing H-bonding nicotinic and isonicotinic acid ligands are reported. Notably, a subtle switching of the H-bonding functionality from the 3- to 4-position of the pyridyl ring leads to a significant change in both the strength of association and the site of adenine binding. Graphical abstract The first examples of adenine binding by isomeric organoplatinum(II) complexes bearing H-bonding nicotinic and isonicotinic acid ligands are reported. Image 1 Highlights • The first examples of non-covalent binding to adenine by organoplatinum(II) complexes are reported. • A switching of the H-bonding group leads to a significant change in both the strength and site of adenine binding. • The nicotinic acid derivative strongly H-bonds to the Watson Crick-site of 9-sec-pentyladenine (9-PA) in CDCl 3 solution. • Conversely, the isonicotinic acid derivative H-bonds to the Hoogsteen site of 9-PA and the binding interaction is limited. [ABSTRACT FROM AUTHOR]