当前位置： SCI文献检索 > JOURNAL OF INORGANIC BIOCHEMISTRY期刊下所有文献 > Preparation, stability, and photoreactivity of thiolato ruthenium polypyridyl complexes: Can cysteine derivatives protect ruthenium-based anticancer complexes?

Preparation, stability, and photoreactivity of thiolato ruthenium polypyridyl complexes: Can cysteine derivatives protect ruthenium-based anticancer complexes?

Abstract：

:Ruthenium polypyridyl complexes may act as light-activatable anticancer prodrugs provided that they are protected by well-coordinated ligands that i) prevent coordination of other biomolecules to the metal center in the dark and ii) can be removed by visible light irradiation. In this paper, the use of monodentate thiol ligands RSH as light-cleavable protecting groups for the ruthenium complex [Ru(tpy)(bpy)(OH2)](PF6)2 ([1](PF6)2; tpy=2,2';6',2″-terpyridine, bpy=2,2'-bypyridine), is investigated. The reaction of [1](2+) with RSH=H2Cys (L-cysteine), H2Acys (N-acetyl-L-cysteine), and HAcysMe (N-acetyl-L-cysteine methyl ester), is studied by UV-visible spectroscopy, NMR spectroscopy, and mass spectrometry. Coordination of the monodentate thiol ligands to the ruthenium complex takes place upon heating to 353 K, but full conversion to the protected complex [Ru(tpy)(bpy)(SR)]PF6 is only possible when a large excess of ligand is used. Isolation and characterization of the two new thiolato complexes [Ru(tpy)(bpy)(κS-HCys)]PF6 ([2]PF6) and [Ru(tpy)(bpy)(κS-HAcys)]PF6 ([3]PF6) is reported. [3]PF6 shows a metal-to-ligand charge-transfer absorption band that is red shifted (λmax=492 nm in water) compared to its methionine analogue [Ru(tpy)(bpy)(κS-HAmet)](Cl)2 ([5](Cl)2, λmax=452 nm; HAmet=N-acetyl-methionine). In the dark the thiolate ligand coordinated to ruthenium is oxidized even by traces of oxygen, which first leads to the sulfenato, sulfinato, and disulfide ruthenium complexes, and finally to the formation of the aqua complex [1](2+). [3]PF6 showed slow photosubstitution of the thiolate ligand by water under blue light irradiation, together with faster photooxidation of the thiolate ligand compared to dark conditions. The use of thiol vs. thioether monodentate ligands is discussed for the protection of anticancer ruthenium-based prodrugs.

journal_name

J Inorg Biochem

journal_title

Journal of inorganic biochemistry

authors

van Rixel VH,Busemann A,Göttle AJ,Bonnet S

doi

10.1016/j.jinorgbio.2015.05.010

subject

Has Abstract

pub_date

2015-09-01 00:00:00

pages

174-81

eissn

0162-0134

issn

1873-3344

pii

S0162-0134(15)30001-5

journal_volume

150

pub_type

杂志文章

在线工具

Preparation, stability, and photoreactivity of thiolato ruthenium polypyridyl complexes: Can cysteine derivatives protect ruthenium-based anticancer complexes?