Organometallic ruthenium -arene complexes

Liu H-K, Bemers-Price SJ, Wang F, Parkinson JA, Xu J, Bella J, Sadler PJ (2006) Diversity in guanine-selective DNA binding modes for an organometallic ruthenium arene complex. Angew Chem Int Ed Engl 45 8153-8156... 

Hu W, Luo Q, Ma X, Wu K, Liu J, Chen Y, Xiong S, Wang J, Sadler PJ, Wang F (2009) Arene control over thiolate to sulfinate oxidation in albumin by organometallic ruthenium anticancer complexes. Chem Eur J 15 6586-6594... 

Ku9ukbay, H., Cebnkaya, B., Guesmi, S., Dixneuf, P.H., New (carbene)ruthenium-arene complexes preparation and uses in catalytic synthesis of furans, Organometallics 1996, 15 2434-2439. 

Nazarov, A. A. et al. Anthracene-Tethered Ruthenium(II) Arene Complexes as Tools To Visualize the Cellular Localization of Putative Organometallic Anticancer Compounds. Inorg. Chem. 51, 3633-3639 (2012). 

Consequently, organometallic ruthenium(II) and osmium(II) arene complexes have recently attracted interest as anticancer agents [51]. The presence of a 7i-bonded arene in Ru11 (and Os11) complexes can have a dramatic influence on their chemical reactivity. There is a delicate balance between electron donation from the arene into the empty Ru 4d orbitals and back-donation from the filled 4d6 orbitals into vacant arene orbitals. This is influenced by the donor-acceptor power of the arene (e.g. hexamethylbenzene as a strong donor, in contrast to biphenyl which may act as acceptor) and by the other ligands on Ru11 which can influence the... 

Novel picolinate derivatives have been synthesised that show hydrolysis rates intermediate between the slow values for the complexes with /V,/V-chelating ligands, and the rapidly-hydrolysing complexes with 0,0- or N,0- amino acidlike chelating ligands. For these organometallic osmium complexes, the hydrolysis rates fall into the range of the active ruthenium-arene relatives (Fig.l) [66]. 

Once the ruthenium or osmium arene organometallic complex is activated with the formation of the aqua species, [Ru/Os(r 6-arene)(OH2)(X)(Y)] (Chart 3), the metal becomes a potential centre for nucleophilic attack by biomolecules. The binding of Run/Osn arene complexes to nucleobases is of special interest, since DNA could be the ultimate target for this class of organometallic complexes. A number of studies have confirmed this postulate [86, 87] and investigated in detail such interactions [53, 54, 72, 88-93]. DNA interactions of Ru and Os arene complexes have recently been reviewed [94],... 

Aird RE, Cummings J, Ritchie AA, Muir M, Morris RE, Chen H, Sadler PJ, Jodrell DI (2002) In vitro and in vivo activity and cross resistance profiles of novel ruthenium(II) organometallic arene complexes in human ovarian cancer. Br J Cancer 86 1652-1657... 

Yan YK, Melchart M, Habtemariam A, Sadler PJ (2005) Organometallic chemistry, biology and medicine ruthenium arene anticancer complexes. Chem Commun 4764-4776... 

Little is known about the chemical nature of the recently isolated carbon clusters (C o> C70, Cg4, and so forth). One potential application of these materials is as highly dispersed supports for metal catalysts, and therefore the question of how metal atoms bind to C40 is of interest. Reaction of C o with organometallic ruthenium and platinum re nts has shown that metals can be attached directly to the carbon framework. Ihe native geometry of transition metal, and an x-ray difi action analysis of the platinum complex [(CgHg)3P]2Pt( () -C6o) C4HgO revealed a structure similar to that known for [(C4Hs)3P]2Pt( n -ethylene). The reactivity of C40 is not like that of relatively electron-rich planar aromatic molecules su( as benzene. The carbon-carbon double bonds of C40 react like those of very electron-deficient arenes and alkcnes. 

Ruthenium arenes are another interesting class of organometallics with proven anticancer activity. The most active complex [( 7 -biphenyl)Ru(ethylene-diamine)Cl] 1 (Scheme 11) had an activity comparable to Garboplatin against a human ovarian cancer cell line. " The interaction of this compound with different biomolecules has been studied, and again, DNA has been suggested as the primary target. It is, however, unclear at present... 

Two main families of organometallic ruthenium(II)-arene complexes (see Fig. 43.1) were developed and studied by Sadler [3, 4] (RM complexes) and Dyson [5, 6] (RAPTA complexes), in which the basic structures present the piano-stool geometry and their reactivity toward biological targets is based on the leaving chloride ligands, as happens with cisplatin. Nevertheless, these two families of compounds besides the similarity of their structure present different characteristics. 

Marchetti P, Pettinari C, Pettinari R, et aL Ruthenium(II)arene complexes bearing tris(pyrazolyl)methanesulfonate capping hgands, electrochemistry, spectroscopic, and X-ray strucmral characterization. Organometallics. 2011 30 6180-6188. 

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