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[Abstract] Metal‐driven self‐assembly afforded a multitude of fascinating supramolecular coordination complexes (SCCs) with applications as catalysts, host–guest, and stimuli‐responsive systems. However, the interest in the biological applications of SCCs is only starting to emerge and thorough characterization of their behavior in biological milieus is still lacking. Herein, we report on the synthesis and detailed in‐cell tracking of a Pt2L2 metallacycle. We show that our hexagonal supramolecule accumulates in cancer cell nuclei, exerting a distinctive blue fluorescence staining of chromatin resistant to UV photobleaching selectively in nucleolar G4‐rich regions. SCC co‐localizes with epitopes of the quadruplex‐specific antibody BG4 and replaces other well‐known G4 stabilizers. Moreover, the photophysical changes accompanying the metallacycle binding to G4s in solution (fluorescence quenching, absorption enhancement) also take place intracellularly, allowing its subcellular interaction tracking.

[Resumen:] Con este proyecto se pretende explorar la aplicación de la química supramolecular en la biomedicina, mediante la síntesis de metalociclos de Pt(II) y Pd(II) que actúen como agentes de unión al ADN, y por tanto, con un posible potencial como agentes antitumorales. Así, en el presente trabajo de fin de grado se ha llevado a cabo la síntesis de dos ligandos derivados del 4,4’-bipiridinio mediante una ruta sintética optimizada y ensayada previamente por el grupo de investigación. A continuación, se realizaron las reacciones de autoensamblaje dirigidas por centros metálicos de Pd(II) y Pt(II) necesarias para obtener los metalociclos correspondientes. Posteriormente, se ha estudiado de la interacción entre los metalociclos de Pt(II) y el ct-ADN mediante dos técnicas: dicroísmo circular y espectroscopia UV-Vis. La caracterización de los compuestos se llevó a cabo por RMN (mono y/o bidimensional) y, cuando fue necesario, espectrometría de masas., [Abstract:] This project was intended to explore the application of supramolecular chemistry in biomedicine, through the synthesis of Pt(II) and Pd(II) metallacycles that act as DNA binders and, therefore, can display potential antitumor activities. Herein, we have carried out the synthesis of two ligands derived from 4,4’-bipyridinium through a synthetic route previously developed and optimized by our research group. Then, Pd(II)/Pt(II)-directed self-assembly of those ligands was performed in order to obtain the corresponding metallacycles. Later, the interaction between the obtained Pt(II) metallacycles and ct-DNA was studied using two different techniques: circular dichroism and UV-Vis spectroscopy. All the compounds were characterized by NMR experiments (1D and/or 2D), and, when possible, by mass spectroscopy., [Resumo:] Con este proxecto preténdese explorar a aplicación de química supramolecular no eido da biomedicina, a través da síntese de metalociclos de Pt(II) e Pd(II) que actúen como axentes de unión ao ADN, e polo tanto poidan mostrar potencial coma axentes antitumorais. Así, no presente traballo de fin de grao levouse a cabo a síntese de dous ligandos derivados do 4,4’-bipiridinio, mediante unha ruta sintética optimizada e ensaiada previamente polo grupo de investigación. A continuación, realizáronse as reaccións de autoensamblaxe dirixida por centros metálicos de Pd(II) e Pt(II), necesarias para obter os metalociclos correspondentes. Posteriormente, estudouse a interacción entre os metalociclos de Pt(II) e o ct-ADN mediante dúas técnicas: dicroísmo circular e espectroscopia UV-Vis. A caracterización dos compostos levouse a cabo por RMN (mono e/ou bidimensional) e, cando foi necesario, espectrometría de masas.

Thiosemicarbazones are formed by the condensation of an aldehyde or ketone with a thiosemicarbazide. They have high coordinative capacity given that they have several potential donor atoms through which they can bind to transition metals. This coordinative capacity can be increased if the R1 and R2 substituents include additional donor atoms. In addition, thiosemicarbazones as well as their semicarbazones analogues have considerable biological and pharmacological interest because of their antibacterial, antiviral and antitumor activity. This communication includes the preparation and characterization of a series of thiosemicarcarbazones and their applications in the synthesis of palladium organometallic compounds

[Abstract] Concentration, temperature and/or solvent polarity control the speciation on the metal-directed self-assembly of a ditopic pyridyl ligand L with cis-protected Pd(II) metal centers. This results into a controllable dynamic system, involving a [Pd2L2]6+ metallacycle and a [Pd4L4]12+ ring-in-ring complex.

Transition metal-containing metallabenzenes and metallabenzynes are organometallic compounds derived from formal replacement of a CH group or a C atom in benzene and benzyne by an isolobal transition metal fragment. The chemistry of these interesting metallaaromatics has received considerable attention in recent years. A number of such complexes have been obtained from various synthetic routes. Interesting chemical properties of these complexes have also been reported. This review summarizes recent progress in the synthesis and reactivity of metallabenzenes and metallabenzynes. (C) 2013 Elsevier B.V. All rights reserved.

Transition metal-containing metallabenzenes and metallabenzynes are organometallic compounds derived from formal replacement of a CH group or a C atom in benzene and benzyne by an isolobal transition metal fragment. The chemistry of these interesting metallaaromatics has received considerable attention in recent years. A number of such complexes have been obtained from various synthetic routes. Interesting chemical properties of these complexes have also been reported. This review summarizes recent progress in the synthesis and reactivity of metallabenzenes and metallabenzynes. (C) 2013 Elsevier B.V. All rights reserved.

This thesis reports the coordination chemistry of phosphinocarbonyl ligands with platinum and describes the influence of phosphine substituents on the mechanism of chelation and the coordination mode of the carbonyl moiety. The ligands synthesised were 2-diphenylphosphinobenzaldehyde (1), 2-diphenylphosphinoacetophenone (2), 2-bis(pentafluorophenyl)phosphinobenzaldehyde (3), and 2-di-tert-butylphosphinobenzaldehyde (4). Compounds 1, 3, and 4 were selected on the basis of their steric bulk and extent to which they donate electron density to the metal. Compound 2 contained the same phosphine substituents to 1, but is the methyl ketone analogue and therefore does not contain the CHO moiety. The cone angle and electronic parameter of compounds 1–4 were compared to the reported values of PPh3, PPh(C6F5)2, and PPhtBu2. Compounds 3 and 4 were similarly bulky, and had larger cone angles than 1. The electron donating capacity of compound 4 was greater than that of 1, and compound 3 was the least electron donating. A new synthetic method for the preparation of 4 is also reported. The coordination chemistry of ligands 1–4 was investigated with platinum(II) and platinum(0) starting materials to assess the influence of the steric and electronic parameters of the phosphine on the chelation of the ligand through the carbonyl to platinum. Coordination of the ligand went through the initial coordination of the phosphine and, depending on the identity of that phosphine, may be followed by chelation of the carbonyl moiety to form a P,C chelate. However, the site of the platinum–carbon bond in the P,C metallacycle depends on the ligand employed. Coordination of the phosphinoaldehyde ligands 1, 3, and 4 produced Pt-C bonds via the C-H activation of the aldehyde CHO group whereas for ketophosphine 2, C-H activation occurred at the α-methyl group. The rate at which C-H activation occurred increased with increasing electron donation from the phosphorus to platinum. Compound 4 chelates to p

There has been much research activity in the chemistry of osmium complexes with an osmium-carbon triple bond. This paper summarizes recent progress in the synthesis, reactivities, and structural properties of osmium carbyne and osmabenzynes complexes. (C) 2006 Elsevier B.V. All rights reserved.

There has been much research activity in the chemistry of osmium complexes with an osmium-carbon triple bond. This paper summarizes recent progress in the synthesis, reactivities, and structural properties of osmium carbyne and osmabenzynes complexes. (C) 2006 Elsevier B.V. All rights reserved.

There has been much research activity in the chemistry of osmium complexes with an osmium-carbon triple bond. This paper summarizes recent progress in the synthesis, reactivities, and structural properties of osmium carbyne and osmabenzynes complexes. (C) 2006 Elsevier B.V. All rights reserved.

This paper describes the preparation and structural characterization of a distorted seven-membered cyclic cumulene. This complex was formed unexpectedly by the reaction of 1,4-bis(trimethylsilyl)buta- 1,3-diyne and the in situ prepared zirconocene complex of n-butene.