TY - JOUR

T1 - Benzothiazole bipyridine complexes of ruthenium(II) with cytotoxic activity

AU - Spillane, Caitriona B.

AU - Fletcher, Nicholas C.

AU - Rountree, Sandra M.

AU - Van Den Berg, Hendrik

AU - Chanduloy, Severine

AU - Morgan, Joy L.

AU - Keene, F. Richard

PY - 2007/8/30

Y1 - 2007/8/30

N2 - A series of benzothiazole-substituted trisbipyridine ruthenium(II) analogues {[Ru(bpy)2(4,5′-bbtb)]2+, [Ru(bpy) 2(5,5′-bbtb)]2+ and [Ru(bpy)2(5-mbtb)] 2+ [bpy is 2,2′-bipyridine, bbtb is bis(benzothiazol-2-yl)-2, 2′-bipyridine, 5-mbtb is 5-(benzothiazol-2-yl),5′-methyl-2,2′- bipyridine]} have been prepared and compared with the complex [Ru(bpy) 2(4,4′-bbtb)]2+ reported previously. From the UV-vis spectral studies, substitution at the 5-position of the bpy causes the ligand-centred transitions to occur at considerably lower energy than for those with the functionality at the 4-position, while at the same time causing the emission to be effectively quenched. However, substitution at the 4-position causes the metal-to-ligand charge transfer to occur at lower energies. Fluorescent intercalator displacement studies indicate that the doubly substituted complexes displace ethidium bromide from a range of oligonucleotides, with the greater preference shown for bulge and hairpin sequences by the Λ enantiomer. Since the complexes only show small variation in the UV-vis spectra on the introduction of calf thymus DNA and a small increase in fluorescence they do not appear to be intercalators, but appear to associate within one of the grooves. All of the reported bisbenzothiazole complexes show reasonable cytotoxicity against a range of human cancer cell lines.

AB - A series of benzothiazole-substituted trisbipyridine ruthenium(II) analogues {[Ru(bpy)2(4,5′-bbtb)]2+, [Ru(bpy) 2(5,5′-bbtb)]2+ and [Ru(bpy)2(5-mbtb)] 2+ [bpy is 2,2′-bipyridine, bbtb is bis(benzothiazol-2-yl)-2, 2′-bipyridine, 5-mbtb is 5-(benzothiazol-2-yl),5′-methyl-2,2′- bipyridine]} have been prepared and compared with the complex [Ru(bpy) 2(4,4′-bbtb)]2+ reported previously. From the UV-vis spectral studies, substitution at the 5-position of the bpy causes the ligand-centred transitions to occur at considerably lower energy than for those with the functionality at the 4-position, while at the same time causing the emission to be effectively quenched. However, substitution at the 4-position causes the metal-to-ligand charge transfer to occur at lower energies. Fluorescent intercalator displacement studies indicate that the doubly substituted complexes displace ethidium bromide from a range of oligonucleotides, with the greater preference shown for bulge and hairpin sequences by the Λ enantiomer. Since the complexes only show small variation in the UV-vis spectra on the introduction of calf thymus DNA and a small increase in fluorescence they do not appear to be intercalators, but appear to associate within one of the grooves. All of the reported bisbenzothiazole complexes show reasonable cytotoxicity against a range of human cancer cell lines.

KW - 2,2′-Bipyridine

KW - Benzothiazol

KW - Cytotoxicity

KW - DNA binding

KW - Ruthenium

U2 - 10.1007/s00775-007-0232-z

DO - 10.1007/s00775-007-0232-z

M3 - Journal article

C2 - 17530304

AN - SCOPUS:34547422304

VL - 12

SP - 797

EP - 807

JO - Journal of Biological Inorganic Chemistry

JF - Journal of Biological Inorganic Chemistry

SN - 0949-8257

IS - 6

ER -