Interaction of a <em>trans</em>-Palladium(II) Complex Containing Planar Amine Ligands with DNA Bases

Abstract

Palladium(II)complexescoordinatedtolargeplanaramineligandsrepresentaleadstructureofconsiderable interestincurrentantitumordrugdesign.However,thequestioniswhetherthesecomplexescanbindtoDNAbases affordingbifunctionaladductsforgreatsterichindranceprovidedbythebulkyligands.Westudiedtheinteractionof thepalladium(II)complex,PdCl 2 L 2 ,whereLwas2鄄hydroxypydridine,withDNAbasesusingdensityfunctionaltheory andcombiningwithisoelectricfocusingpolarizedcontinuum(IEF鄄PCM)solvationmodel.Activationfreeenergiesfor thecomplexmonofunctionalandbifunctionalbindingtoDNAbaseswerelowerthanthoseforplatinum鄄based antitumoragents.Allreactionsunderstudywereexothermicinaqueoussolution.Theresultsindicatethatthelarge planaramineligandsinthepalladiumcomplexesdonothinderformationofbifunctionaladductswithDNAbases,and theratesformonofunctionalandbifunctionalbindingtoDNAbasestobelargerthanthoseofplatinum鄄basedagents.