title: Photoactivation of trans diamine platinum complexes in aqueous solution and effect on reactivity towards nucleotides.
abstract: We show that UVA irradiation (365nm) of the Pt(IV) complex trans,trans,trans-[Pt(IV)Cl(2)(OH)(2)(dimethylamine)(isopropylamine)] (1), induces reduction to Pt(II) photoproducts. For the mixed amine Pt(II) complex, trans-[Pt(II)Cl(2)(isopropylamine)(methylamine)] (2), irradiation at 365nm increases the rate and extent of hydrolysis, triggering the formation of diaqua species. Additionally, irradiation increases the extent of reaction of complex 2 with guanosine-5'-monophosphate and affords mainly the bis-adduct, while reactions with adenosine-5'-monophosphate and cytidine-5'-monophosphate give rise only to mono-nucleotide adducts. Density Functional Theory calculations have been used to obtain insights into the electronic structure of complexes 1 and 2, and their photophysical and photochemical properties. UVA-irradiation can contribute to enhanced cytotoxic effects of diamine platinum drugs with trans geometry.
authors.affiliation: Departamento de Química Inorgánica, Universidad Autónoma de Madrid, 28049 Madrid, Spain.
authors.forename: Leticia
authors.initials: L
authors.lastname: Cubo
authors.forename: Ana M
authors.initials: AM
authors.lastname: Pizarro
authors.forename: Adoración Gómez
authors.initials: AG
authors.lastname: Quiroga
authors.forename: Luca
authors.initials: L
authors.lastname: Salassa
authors.forename: Carmen
authors.initials: C
authors.lastname: Navarro-Ranninger
authors.forename: Peter J
authors.initials: PJ
authors.lastname: Sadler
mesh_terms: D000970:Antineoplastic Agents / Q000737:chemistry; D002853:Chromatography, Liquid; D003959:Diamines / Q000737:chemistry*; D009682:Magnetic Resonance Spectroscopy; D013058:Mass Spectrometry; D008958:Models, Molecular; D015394:Molecular Structure; D009711:Nucleotides / Q000737:chemistry*; D009944:Organoplatinum Compounds / Q000737:chemistry*; D010777:Photochemistry / Q000379:methods*
chemical_list: D000970:Antineoplastic Agents; D003959:Diamines; D009711:Nucleotides; D009944:Organoplatinum Compounds