Synthesis, DNA-binding and photocleavage studies of ruthenium complexes [Ru(bpy)2(mitatp)]2+ and [Ru(bpy)2(nitatp)]2+.
Two new ruthenium complexes [Ru(bpy)2(mitatp)](ClO4)2 1 and [Ru(bpy)2(nitatp)](ClO4)2 2 (bpy = 2,2'-bipyridine, mitatp = 5-methoxy-isatino[1,2-b]-1,4,8,9-tetraazatriphenylene, nitatp = 5-nitro-isatino[1,2-b]-1,4,8,9-tetraazatriphenylene) have been synthesized and characterized by elemental analysis, 1H NMR, mass spectrometry and cyclic voltammetry. Spectroscopic and viscosity measurements proved that the two Ru(II) complexes intercalate DNA with larger binding constants than that of [Ru(bpy)2(dppz)]2+ (dppz = dipyrido[3,2-a:2',3'-c]phenazine) and possess the excited lifetime of microsecond scale upon binding to DNA. Both complexes can efficiently photocleave pBR322 DNA in vitro under irradiation. Singlet oxygen (1O2) was proved to contribute to the DNA photocleavage process, the 1O2 quantum yields was determined to be 0.43 and 0.36 for 1 and 2, respectively. Moreover, a photoinduced electron transfer mechanism was also found to be involved in the DNA cleavage process.
Yu
Hui-Juan
HJ
MOE Laboratory of Bioinorganic and Synthetic Chemistry, State Key Laboratory of Optoelectronic Materials and Technologies, School of Chemistry and Chemical Engineering, Sun Yat-Sen University, Guangzhou 510275, PR China.
Huang
Shu-Mei
SM
Li
Lv-Ying
LY
Jia
Hai-Na
HN
Chao
Hui
H
Mao
Zong-Wan
ZW
Liu
Jian-Zhong
JZ
Ji
Liang-Nian
LN
D004247:DNA / Q000737:chemistry* / Q000378:metabolism / Q000528:radiation effects; D007364:Intercalating Agents / Q000737:chemistry; D008024:Ligands; D009942:Organometallic Compounds / Q000138:chemical synthesis / Q000737:chemistry*; D010782:Photolysis; D012428:Ruthenium / Q000737:chemistry*; D026082:Singlet Oxygen
D007364:Intercalating Agents; D008024:Ligands; D009942:Organometallic Compounds; D026082:Singlet Oxygen; D012428:Ruthenium; D004247:DNA