Structural And Synthetic Studies On Some Organometallic Complexes Of Platinumii

Author : Yuen-Ting Shum
Publisher : Open Dissertation Press
ISBN 13 : 9781361428115
Total Pages : pages
Book Rating : 4.4/5 (281 download)

DOWNLOAD NOW!

Download or read book Functionalized Platinum (II) and Gold (I) Acetylide Complexes written by Yuen-Ting Shum and published by Open Dissertation Press. This book was released on 2017-01-27 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: This dissertation, "Functionalized Platinum (II) and Gold (I) Acetylide Complexes: Structural and Spectroscopic Properties and Anticancer Activities" by Yuen-ting, Shum, 岑婉婷, was obtained from The University of Hong Kong (Pokfulam, Hong Kong) and is being sold pursuant to Creative Commons: Attribution 3.0 Hong Kong License. The content of this dissertation has not been altered in any way. We have altered the formatting in order to facilitate the ease of printing and reading of the dissertation. All rights not granted by the above license are retained by the author. Abstract: Abstract of thesis entitled FUNCTIONALIZED PLATINUM(II) AND GOLD(I) ACETYLIDE COMPLEXES. STRUCTURAL AND SPECTROSCOPIC PROPERTIES AND ANTICANCER ACTIVITIES Submitted by SHUM YUEN TING For the degree of Doctor of Philosophy at The University of Hong Kong in April 2007 Planar [Pt(terpy)X] complexes (terpy = 2,2':6',2''-terpyridine; X = Cl, SR) have frequently been cited as classic DNA metallointercalators in bioinorganic chemistry; + however, application studies of [Pt(terpy)L] (L = monoanionic ligand) and its derivatives in metal-based therapeutics are limited. In this work, a series of platinum(II) terpyridine complexes containing different glycosylated acetylide and arylacetylide ligands were prepared and characterized, the photophysical properties of which were investigated. A low-energy absorption band at 409-476 nm, which was assignable to a MLCT transition was observed in its electronic absorption spectra. Upon photoexcitation, intense emission bands at 513-733 nm were observed and were believed to originate from the excited states of 3 3 MLCT and LLCT character. Cytotoxic activities of the ''Pt(terpy)(glycosylated arylacetylide)'' system with significant inhibitory effect toward a series of carcinoma cell lines were discovered. [Pt( Bu terpy)(L3)](CF SO ) (L3 = 4-ethynylphenoxy 3 3 3 -2,3,4,6-tetra-O-acetyl-β-D-glucopyranoside) (IC = 0.06-0.1 M) was found to be 50 i260-fold more effective in growth inhibition of the human brain cancer cell line (SF-268) than cisplatin. The binding interactions of selected platinum(II) complexes 4 5 -1 3 to calf-thymus DNA featured binding constants of 10-10 mol dm . Significantly, the spectral data were found to support a specific binding mode at the AT sequences of DNA for selected complexes. The results of cytometry experiments showed that [Pt( Bu terpy)(L3)](CF SO ) 3 3 3 induce 52.4% apoptosis in NCI-H460 cells. Based on microarray and Western blotting analyses, down-regulation of anti-apoptotic proteins, including Bcl-2 and caspase-3, were observed for platinum-treated NCI-H460 cells. When taken together, the [Pt( Bu terpy)(L3)](CF SO)-induced apoptosis in NCI-H460 cells should 3 3 3 normally occur via the mitochondrial pathway. A family of mono- and binuclear Cy P-supported gold(I) complexes which contained various π-conjugated arylacetylide ligands, were prepared and characterized. The lowest-energy singlet transitions were predominately intraligand in nature and exhibited both phenyl and acetylenic (ππ*) character. The organic triplet emissions of arylacetylide groups were thus "illuminated" at ambient conditions by ligation to the [Au(PCy )] fragment. Strong photoluminescence was detected in solid and solution states of the gold(I) complexes under ambient conditions with lifetimes in the microsecond regime. Selected gold(I) complexes were also subjected to cytotoxicity analysis; only [Au(PCy )(C≡CC H )] showed cytotoxicities (IC = 3 10 7 50 4.9-14.5 M) that were comparable to clinical cisplatin. An acetylide ligand that was appended with lomefloxacin moiety was coordinated to ii with gold(I) and platinum(II) complexes to form [CyPAu(lome)] and [Pt( Bu tpy)(lome)] (CF SO ) (lome = modified lomefloxacin), both of which were 3 3 3 structurally characterized. Tw