Ruthenium poly-pyridyl compounds, RuLH, RuLCOOH and RuLOMe have been synthesized and their photophysical properties have been studied. It was shown that the sub stitution of one bipyridine ligand of a ruthenium tris-bipyridine with a stilben oid-bipyridine ligand does not affect the HOMO energy levels of the ruthenium ce nter. However, this modification results in lowering the LUMO energy levels by 0 .2 eV which in turn leads to a red-shift in the absorption spectrum. Also, we r eport the synthesis and characterization of a novel ruthenium-based dye, TG6. Th is complex shows good absorption properties in comparison to the one of the most efficient sensitizer (N3 dye), which may allow us to present this dye as a prom ising sensitizer in dye-sensitized solar cell systems.
This book will describe Ruthenium complexes as chemotherapeutic agent specifically at tumor site. It has been the most challenging task in the area of cancer therapy. Nanoparticles are now emerging as the most effective alternative to traditional chemotherapeutic approach. Nanoparticles have been shown to be useful in this respect. However, in view of organ system complicacies, instead of using nanoparticles as a delivery tool, it will be more appropriate to synthesize a drug of nanoparticle size that can use blood transport mechanism to reach the tumor site and regress cancer. Due to less toxicity and effective bio-distribution, ruthenium (Ru) complexes are of much current interest. Additionally, lumiscent Ru-complexes can be synthesized in nanoparticle size and can be directly traced at tissue level. The book will contain the synthesis, characterization, and applications of various Ruthenium complexes as chemotherapeutic agents. The book will also cover the introduction to chemotherapy, classification of Ru- complexes with respect to their oxidation states and geometry, Ruthenium complexes of nano size: shape and binding- selectivity, binding of ruthenium complexes with DNA, DNA cleavage studies and cytotoxicity. The present book will be more beneficial to researchers, scientists and biomedical. Current book will empower specially to younger generation to create a new world of ruthenium chemistry in material science as well as in medicines. This book will be also beneficial to national/international research laboratories, and academia with interest in the area of coordination chemistry more especially to the Ruthenium compounds and its applications.
Edited by a team of highly respected researchers combining their expertise in chemistry, physics, and medicine, this book focuses on the use of rutheniumcontaining complexes in artificial photosynthesis and medicine. Following a brief introduction to the basic coordination chemistry of ruthenium complexes and their synthesis in section one, as well as their photophysical and photochemical properties, the authors discuss in detail the major concepts of artificial photosynthesis and mechanisms of hydrogen production and water oxidation with ruthenium in section two. The third section of the text covers biological properties and important medical applications of ruthenium complexes as therapeutic agents or in diagnostic imaging. Aimed at stimulating research in this active field, this is an invaluable information source for researchers in academia, health research institutes and governmental departments working in the field of organometallic chemistry, green and sustainable chemistry as well as medicine/drug discovery, while equally serving as a useful reference also for scientists in industry.
The main goal of this thesis was synthesis and preliminary characterization of novel ruthenium(II) polypyridyl complexes bearing biologically active molecules as potential theranostic agents. Luminescence for the diagnostic applications, and cytotoxicity for the anticancer, therapeutic applications are considered as the theranostic properties. Four new ligands containing biologically active moieties - 5-(4-4'-methyl-[2,2'-bipyridine]-4-ylbut-1-yn-1-yl)pyridine-2-carbaldehyde semicarbazone (L1), 3-(5-4'-methyl-[2,2'-bipyridine]-4-ylpentyl)imidazolidine-2,4-dione (L2), 5,5-dimethyl-3-(5-4'-methyl-[2,2'-bipyridine]-4-ylpentyl)imidazolidine-2,4-dione (L3) and [1-(5-4'-methyl-[2,2'-bipyridine]-4-ylpentyl)-2,5-dioxoimidazolidin-4-yl]urea (L4) were synthesized and characterized. The ligands were used to obtain nine novel ruthenium(II) polypyridyl complexes. Six complexes were synthesized with ligand L1 ([Ru(bpy)2(L1)]2+, [Ru(Mebpy)2(L1)]2+, [Ru(tBubpy)2(L1)]2+, [Ru(Phbpy)2(L1)]2+, [Ru(dip)2(L1)]2+, [Ru(SO3dip)2(L1)]2-) and three with ligands L2, L3 and L4 ([Ru(bpy)2(L2)]2+, [Ru(bpy)2(L3)]2+, [Ru(bpy)2(L4)]2+) (bpy = 2,2'-bipyridine, Mebpy = 4,4'-dimethyl-2,2-bipyridine, tBubpy = 4,4'-tert-butyl-2,2'-bipyridine, Phbpy = 4,4'-diphenyl-2,2-bipyridine, dip = 4,7-diphenyl-1,10-phenantroline and SO3dip = 4,7-di-(4-sulfonatophenyl)-1,10-phenantroline). The spectroscopic and photophysical properties of those complexes were determined. The presence of ligands L1-L4 in the structure of the complex decreased luminescence quantum yield and luminescence lifetime in comparison with unmodified [Ru(bpy)3]2+ complex. The theoretical calculations have shown that ligands L1-L4 do not have influence on ruthenium core geometry. However, they increased the energy of the HOMO that resulted in a shorter band gap. The simulated electronic absorption spectra were in a good agreement with the experimental data. The interactions between the studied ruthenium complexes and human serum albumin (HSA) were investigated. All studied Ru(II) complexes exhibited strong affinity to HSA with the association constant 105 M-1s-1, which suggests formation of Ru complex-HSA adducts. It was also determined that ruthenium complexes most likely bind to the hydrophobic pocket of protein, located in Sudlow's site I in the subdomain II A. Preliminary cytotoxicity evaluation for the studied ruthenium complexes showed their cytotoxic activity towards cancer cell lines. Those results, together with good luminescence properties of the studied ruthenium complexes (luminescence lifetimes and luminescence quantum yield) make them interesting candidates for potential theranostic applications.
Cyclometalated Ruthenium (II) and RAPTA species were synthesized, characterized and evaluated on their photophysical properties and potential as anti-cancer agents. The binding affinity to yeast RNA of one of the newly synthesized compounds containing a thiophene group (LM5400) was compared to its literature precursor (Compound B) containing a phenyl group under gel electrophoresis. Results indicated that the bands of compounds; Compound A, LM3000, Compound B and LM5400 when incubated with yeast RNA, were similar to the control with the expectation of the band of LM5400 being more faint relative to the rest whenever samples were incubated for 24hrs. Photophysical experiments on cyclometalated ruthenium (II) compounds (CompoundA, LM3000, Compound B, LM5400) indicated that these compounds have an absorbance around 360 nm respectively but do not fluoresce due to extremely low emission values. Four hydrolysis studies were done on the cyclometalated ruthenium (II) species under various conditions and monitored via UV/Vis and H-NMR. Underall conditions, the absorbance and the NMR data the complexes with the j6-benzene ring (Compound A and LM3000) changed under aqueous and chloride solutions. In contrast, the absorbance of the complexes with the j6-cymene rings (Compound B and LM5400) only changed upon increased concentration. All compounds synthesized were characterized by NMR. Crystal structures were obtained for newly synthesized compounds, LM3000 and LM5400.
Ruthenium compounds constitute a versatile class of catalysts for important synthetic transformations in organic chemistry. The ability of ruthenium to access different oxidation states and to accommodate a large variety of ligands in various coordination geometries gives rise to numerous different metal complexes. These characteristics have led to the use of a large variety of ruthenium complexes in diverse types of research areas such as artificial photosynthesis, photomolecular devices, studies on biological macromolecules, catalytic oxidation of water and organic substrates, and organic synthesis. This book presents current research from across the globe in the study of ruthenium across a broad spectrum of topics.
