Efficient phosphodiester hydrolysis by luminescent terbium(III) and europium(III) complexes.

(5)D(4)), along with nonradiative deactivation mechanisms of the excited states of europium via multiphonon decays and the ligand-to-metal charge transfer state. Lifetime measurements of the (5)D(4) and (5)D(0) excited levels for 1 and 2, respectively, indicated the numbers of coordinated water molecules for the complexes. -->
Substance Nomenclature: 0 (Organophosphates)
0 (bis(2,4-dinitrophenyl) phosphate)
06SSF7P179 (Terbium)
444W947O8O (Europium)
9007-49-2 (DNA)
Entry Date(s): Date Created: 20100608 Date Completed: 20101012 Latest Revision: 20131121
Update Code: 20240829
DOI: 10.1021/ic100549u
PMID: 20524622
Autor: Camargo MA; Laboratório de Bioinorgânica e Crystalografia (LABINC), Departamento de Química, Universidade de São Paulo, Avenue Bandeirantes 3900, 14040-901, Ribeirão Preto, São Paulo, Brazil., Neves A, Bortoluzzi AJ, Szpoganicz B, Fischer FL, Terenzi H, Serra OA, Santos VG, Vaz BG, Eberlin MN
Jazyk: angličtina
Zdroj: Inorganic chemistry [Inorg Chem] 2010 Jul 05; Vol. 49 (13), pp. 6013-25.
DOI: 10.1021/ic100549u
Abstrakt: The synthesis and structures of two new isostructural mononuclear [Ln(L)(NO(3))(H(2)O)(3)](NO(3))(2) complexes, with Ln = Tb (complex 1) and Eu (complex 2), which display high activity in the hydrolysis of the substrate 2,4-bis(dinitrophenyl)phosphate, are reported. These complexes displayed catalytic behavior similar to the mononuclear gadolinium complex [Gd(L)(NO(3))(H(2)O)(3)](NO(3))(2) previously reported by us (Inorg. Chem. 2008, 47, 2919-2921); one hydrolysis reaction in two stages where the diesterase and monoesterase activities could be monitored separately, with the first stage dependent on and the second independent of the complex concentration. Through potentiometric studies, electrospray ionization mass spectrometry (ESI-MS) analysis, and determination of the kinetic behaviors of 1 and 2 in acetonitrile/water solution, the species present in solution could be identified and suggested a dinuclear species, with one hydroxo group, as the most prominent catalyst under mild conditions. The complexes show high activity (k(1) = 7 and 18 s(-1) for 1 and 2, respectively) and catalytic efficiency. Complexes 1 and 2 were found to be active toward the cleavage of plasmid DNA, and complete kinetic studies were carried out. Studies with a radical scavenger (dimethylsulfoxide) confirmed the hydrolytic action of 1 and 2 in the cleavage of DNA. Studies on the incubation of distamycin with plasmid DNA suggested that 1 and 2 are regio-specific, interacting with the minor groove of DNA. These complexes displayed luminescent properties. Complex 1 showed higher emission intensity than 2 due to a more efficient energy transfer between triplet and emission levels of terbium (T --> (5)D(4)), along with nonradiative deactivation mechanisms of the excited states of europium via multiphonon decays and the ligand-to-metal charge transfer state. Lifetime measurements of the (5)D(4) and (5)D(0) excited levels for 1 and 2, respectively, indicated the numbers of coordinated water molecules for the complexes.
Databáze: MEDLINE
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