Gold(III) compounds of 1,4,7-triazacyclononane showing high cytotoxicity against A-549 and HCT-116 tumor cell lines.

State Key Laboratory of Coordination Chemistry, Nanjing University, Nanjing 210093, PR China.
Journal of Inorganic Biochemistry (Impact Factor: 3.2). 06/2006; 100(5-6):939-45. DOI:10.1016/j.jinorgbio.2005.12.020
Source: PubMed

ABSTRACT Two gold(III) compounds [Au(TACN)Cl(2)]Cl (1) and [Au(TACN)Cl(2)][AuCl(4)] (2) (where TACN=1,4,7-triazacyclononane), have been synthesized and characterized by electrospray ionization mass spectrometry (ESI-MS), (1)H NMR spectroscopy and elemental analyses. The structure of compound 2 was determined by X-ray crystallography, in which TACN coordinates to the gold(III) center in a bidentate mode and the unbound amine group forms a very short intramolecular Au-H(-N) contact (1.91A). Biological activity data showed that compound 1 is more cytotoxic than cisplatin against A-549 and HCT-116 tumor cell lines. The interactions of compound 1 with CT-DNA were studied by UV-Vis, fluorescence and CD spectroscopy, which suggests that compound 1 can induce the distortion of DNA double helix.

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Pengfei Shi