Yun-Jun Liu

Synthesis, DNA-binding, photocleavage, cytotoxicity and antioxidant activity of ruthenium (II) polypyridyl complexes

Two new ligands maip (1a), paip (1b) with their ruthenium (II) complexes [Ru(bpy)(2)(maip)](ClO(4))(2) (2a) and [Ru(bpy)(2)(paip)](ClO(4))(2) (2b) have been synthesized and characterized. The results show that complexes 2a and 2b interact with DNA through intercalative mode. The cytotoxicity of these compounds has been evaluated by MTT assay. The experiments on antioxidant activity show that these compounds exhibit good antioxidant activity against hydroxyl radical (OH).

Synthesis of ruthenium(II) complexes and characterization of their cytotoxicity in vitro, apoptosis, DNA-binding and antioxidant activity

A new ligand DBHIP and its two ruthenium (II) complexes [Ru(bpy)(2)(DBHIP)](ClO(4))(2) (1) and [Ru(phen)(2)(DBHIP)](ClO(4))(2) (2) have been synthesized and characterized. The binding behaviors of the two complexes to calf thymus DNA were investigated by absorption spectra, viscosity measurements, thermal denaturation and photoactivated cleavage. The DNA-binding constants for complexes 1 and 2 have been determined to be 8.87+/-0.27 x 10(4)M(-1) (s=1.83) and 1.32+/-0.31 x 10(5)M(-1) (s=1.84). The results suggest that these complexes interact with DNA through intercalative mode. The cytotoxicity of DBHIP, complexes 1 and 2 has been evaluated by MTT assay. The apoptosis assay was carried out with acridine orange/ethidium bromide (AO/EB) staining methods. The studies on the mechanism of photocleavage demonstrate that superoxide anion radical (O(2)(-)) and singlet oxygen ((1)O(2)) may play an important role.

Synthesis, cellular uptake, apopotosis, cytotoxicity, cell cycle arrest, interaction with DNA and antioxidant activity of ruthenium(II) complexes

A new ligand and two ruthenium(II) complexes [Ru(bpy)(2)(DNPIP)](ClO(4))(2)1 and [Ru(bpy)(2)(DAPIP)](ClO(4))(2)2 were synthesized and characterized. The DNA-binding constants for complexes 1 and 2 were determined to be 2.24 (±0.30)xa0×xa010(5)xa0M(-1) (sxa0=xa01.29) and 6.34 (±0.32)xa0×xa010(4)xa0M(-1) (sxa0=xa02.84). The photocleavage of pBR322 DNA by Ru(II) complexes was investigated. The cytotoxicity of complexes 1 and 2 were assessed against three tumor cell lines. The apoptosis and cellular uptake were studied. The retardation assay of pGL 3 plasmid DNA was explored. The cell cycle arrest was analysized by flow cytometry. The antioxidant activities of the ligand and complexes were also investigated.

Synthesis, structure, DNA-binding properties, and cytotoxicity of ruthenium(II) polypyridyl complexes.

Many ruthenium(II) complexes show high antitumor activities, and the in vitro antitumor activities are usually related to DNA binding. We designed and synthesized two RuII polypyridyl complexes, [Ru(dmp)2(fpp)]2+ (dmp=2,9‐dimethyl‐1,10‐phenanthroline; fpp=2‐[3,4‐(difluoromethylenedioxy)phenyl]imidazo[4,5‐f]u2009[1,10]phenanthroline and [Ru(phen)2(fpp)]2+ (phen=1,10‐phenanthroline). The DNA‐binding properties of these complexes have been investigated by spectroscopic titration, DNA melting experiments, viscosity measurements, and photoactivated cleavage. The mechanism studies of photocleavage revealed that singlet oxygen (1O2) and superoxide anion radical (O

In vitro cytotoxicity, apoptosis, DNA-binding, and antioxidant activity studies of ruthenium (II) complexes.

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2-(3,5-Dibromo-4-hydroxyphenyl)imidazo[4,5-f][1,10]phenanthrolinoruthenium(II) complexes: synthesis, characterization, cytotoxicity, apoptosis, DNA-binding and antioxidant activity

) may play an important role in the photocleavage. The cytotoxicity of complexes 1 and 2 have been evaluated by MTT (3‐(4,5‐dimethylthiazol‐2‐yl)‐2,5‐diphenyl‐2H‐tetrazolium bromide) method; complex 2 shows slightly higher anticancer potency than 1 does against all the cell lines screened.

Ruthenium(II) complexes: synthesis, cytotoxicity in vitro, apoptosis, DNA-binding, photocleavage, and antioxidant activity studies

Two new ligands maip (1) (maip = 2-(3-aminophenyl)imizado[4,5-f][1,10]phenanthroline), paip (2) (paip = 2-(4-aminophenyl)imidazo[4,5-f][1,10]phenanthroline), and their ruthenium (II) complexes [Ru(phen)(2)(maip)](ClO(4))(2) (3) and [Ru(phen)(2)(paip)](ClO(4))(2) (4) (phen = 1,10-phenanthroline) have been synthesized and characterized. The cytotoxicity of these compounds was evaluated by MTT [3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide] assay. The apoptosis assay was carried out with acridine orange/ethidium bromide staining methods. The DNA-binding behaviors of complexes 3 and 4 were investigated by viscosity measurements, thermal denaturation, photocleavage, and spectroscopic methods. The results show that the two complexes intercalate into the base pairs of DNA. In the presence of a complex, apoptosis of BEL-7402 cells was observed. Experiments show that these compounds exhibit antioxidant activity against hydroxyl radicals.

Ruthenium(II) polypyridyl complexes: synthesis and studies of DNA binding, photocleavage, cytotoxicity, apoptosis, cellular uptake, and antioxidant activity.

A new ligand DBHIP and its two ruthenium(II) complexes [Ru(dmb)2(DBHIP)](ClO4)2 (1) and [Ru(dmp)2(DBHIP)](ClO4)2 (2) have been synthesized and characterized. The cytotoxicity of DBHIP and complexes 1 and 2 has been assessed by MTT assay. The apoptosis studies were carried out with acridine orange/ethidium bromide (AO/EB) staining methods. The binding behaviors of these complexes to calf thymus DNA (CT-DNA) were studied by absorption titration, viscosity measurements, thermal denaturation and photoactivated cleavage. The DNA-binding constants of complexes 1 and 2 were determined to be 8.64xa0±xa00.16xa0×xa0104 (sxa0=xa01.34) and 2.79xa0±xa00.21xa0×xa0104 (sxa0=xa02.17)xa0M−1. The results suggest that these complexes interact with DNA through intercalative mode. The studies on the mechanism of photocleavage demonstrate that superoxide anion radical (O2•–) and singlet oxygen (1O2) may play an important role in the DNA cleavage. The experiments on antioxidant activity show that these compounds also exhibit good antioxidant activity against hydroxyl radical (OH•).

DNA-binding and photocleavage, cytotoxicity, apoptosis and antioxidant activity studies of ruthenium(II) complexes

Two new ruthenium(II) complexes, [Ru(dmp)2(APIP)](ClO4)2 (1) (APIPu2009=u20092-(2-aminophenylimidazo[4,5-f][1,10]phenanthroline), dmpu2009=u20092,9-dimethyl-1,10-phenanthroline) and [Ru(dmp)2(HAPIP)](ClO4)2 (2) (HAPIPu2009=u20092-(2-hydroxyl-5-aminophenyl)imidazo[4,5-f][1,10]phenanthroline), were synthesized and characterized. The DNA-binding properties of these complexes were investigated by absorption titration, viscosity measurements, and photoactivated cleavage. The DNA-binding constants for 1 and 2 have been determined to be 2.3 (±u20090.3)u2009×u2009104 (molu2009L−1)−1 and 3.3 (±u20090.4)u2009×u2009104 (molu2009L−1)−1. The results indicate that 1 and 2 interact with DNA through intercalative mode. The cytotoxicities of 1 and 2 were assessed against BEL-7402, HepG-2 and MCF-7 cell lines using standard MTT assay. The apoptosis induced by these complexes was studied with the acridine orange/ethidium bromide staining method. The antioxidant activity on hydroxyl radical was also investigated.

Ruthenium(II) complexes of 2-(2′-pyridyl)naphthoimidazole: synthesis, characterization and DNA-binding studies

Two ruthenium (II) complexes [Ru(dmb)2(APIP)](ClO4)2 (APIP=2-(2-aminophenyl)imidazo[4,5-fu2009][1,10]phenanthroline, dmb=4,4-dimethyl-2,2-bipyridine; 1) and [Ru(dmb)2(HAPIP)](ClO4)2 (HAPIP=2-(2-hydroxyl-4-aminophenyl)imidazo[4,5-fu2009][1,10]phenanthroline; 2) were synthesized and characterized. DNA binding was investigated by electronic absorption titration, luminescence spectra, thermal denaturation, viscosity measurements, and photocleavage. The DNA binding constants for complexes 1 and 2 were 4.20 (±0.14)×10(4) and 5.45 (±0.15)×10(4) M(-1). The results suggest that these complexes partially intercalate between the base pairs. The cytotoxicity of complexes 1 and 2 was evaluated by MTT assay. Cellular uptake was observed under fluorescence microscopy; complexes 1 and 2 can enter into the cytoplasm and accumulate in the nuclei. Apoptosis and the antioxidant activity against hydroxyl radicals (•OH) were also explored.