In this article, we describe the process of binding riboflavin to a simple tetradents ligand substituted in α- position from TPAs types, by reacting bromotetraacetate with TPA one pyridine rings nitrile group and two other halogen atoms. This type ligands showed very important properties for activation transfer oxygen substrate presence iron salt. After were obtained, was reduced an amine where...

The synthesis and characterization of eight new bis-cyclometalated compounds [M(ptpy)2(N^N)]PF6 (ptpy=2-(p-tolyl)pyridinato; N^N=5-chloro-1,10-phenanthroline: M=Rh, 1; M=Ir, 2); N^N=5-methyl-1,10-phenanthroline: 3; 4; N^N=4,4’-diphenyl-2,2’-bipyridine: 5; 6; N^N=4,4’-diamino-2,2’-bipyridine: 7; 8) are described. All were characterized by spectroscopic means. Additionally, the molecular structur...

Two types of N,C,N-chelated pnictinidenes, i.e., [2-(RNHCH2)-6-(RN ═ CH)C6H3]E (1-E-R) and [2,6-(RN═CH)2C6H3]E (2-E-R, where E = As, Sb, Bi), are targeted in this study. 2-E-R could be obtained by simple reduction respective precursors [2,6-(RN═CH)2C6H3]ECl2 (i.e., (2-E-R)Cl2) with KC8 for or Bi R being tBu, Ad, Dipp. By contrast, the utilization a bulky hydride, K-selectride, allowed isolation...

The bulky 2,5-dimethylthiophene (2,5-Me2T) reacts at 60 degrees C with TpMe2Ir(C2H4)2 to give a mixture of two TpMe2Ir(III) hydride products, 3 and 4, that contain in addition a thienyl (3) or a thienyl-derived ligand (4). For the generation of 3 only sp2 C-H activation is needed, but the formation of 4 requires also the activation of an sp3 C-H bond and the formation of a new C-C bond (between...

A series of Ru(II) complexes that behave as water oxidation catalysts were prepared involving a tetradentate equatorial ligand and two 4-substituted pyridines as the axial ligands. Two of these complexes were derived from 2,9-di-(pyrid-2'-yl)-1,10-phenanthroline (dpp) and examine the effect of incorporating electron-donating amino and bulky t-butyl groups on catalytic activity. A third complex ...

The physiological implications of lysophosphatidic acid occupancy of individual receptors are largely unknown because selective agonists/antagonists are unavailable currently. The molecular cloning of three high-affinity lysophosphatidic acid receptors, LPA1, LPA2, and LPA3, provides a platform for developing receptor type-selective ligands. Starting with an N-acyl ethanolamide phosphate LPA an...

A general inability to carry out extensive variations in the electronic characteristics of proximal heme iron ligands in heme proteins has hampered efforts to obtain a clear understanding of the role of the proximal heme iron ligand in the activation of oxygen and peroxide. The disadvantage of the frequently applied site directed mutagenesis technique is that it is limited by the range of natur...