Synthesis, DNA-binding and photocleavage studies of Ru(II) complexes of phenyl-(4,5,9,14-tetraaza-benzo[b]triphenylen-1,1-yl)-methanone

ArticleinJournal of Chemical Sciences 121(4):397-405 · July 2009with20 Reads
DOI: 10.1007/s12039-009-0046-3
Abstract
A novel polypyridyl ligand phenyl-(4,5,9,14-tetraaza-benzo[b]triphenylen-1,1-yl)-methanone (PTBM) and its complexes [Ru(phen)2(PTBM)]2+ (1) (phen = 1,10-phenanthroline) and [Ru(bpy)2(PTBM)]2+ (2) (bpy = 2,2′-bipyridine) have been synthesized and characterized by elemental analysis, mass spectroscopy, and 1H NMR. The DNA-binding properties of the two complexes were investigated by spectroscopic and viscosity measurements. The results indicate that both complexes bind to DNA via an intercalative mode and the DNA-binding affinity of complex 1 is greater than that of complex 2. When irradiated at 365 nm, complex 1 was found to be a more-effective DNA-cleaving agent than complex 2.
    • "The current observed electronic spectra changes may be interpreted as the results of an outside binding between TCPC and ct-DNA, which is similar to its manganese and iron complex [13,14] and its porphyrin analogue [16]. The intrinsic-binding constant Kb of TCPC and ct-DNA might be obtained using the following Equation [17]: "
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    • "It also reduces the inflammatory process of granulation (Giełdanowski & Skowrońska, 1980). It is used in the treatment of cervical cancer, endometrial cancer, pancreatic cancer, prostate cancer, thyroid cancer, breast cancer, lung cancer, soft tissue sarcoma, osteosarcoma, and gestational topoblastic tumors (Alfaro, Delgado, Cárabez, Anguiano, & Aceves, 2013; Staropoli et al., 2014; Tan, Chen, Shen, & Lianga, 2009). In order to gain molecular insight of ADM-DNA interaction, we utilized UV spectroscopy, CD polarimetry, fluorescence spectroscopy, Fourier transform infra red spectroscopy (FTIR), molecular modeling, and isothermal titration calorimeter that are very sensitive and suitable for exploring DNA ligand interaction. "
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