Dalton Transactions

doi: 10.1039/C5DT90088Cpmid: N/A

doi: 10.1039/c5dt90088cpmid: N/A

doi: 10.1039/C5DT90089Apmid: N/A

doi: 10.1039/c5dt90089apmid: N/A

doi: 10.1039/C5DT90090Epmid: N/A

doi: 10.1039/c5dt90090epmid: N/A

Mendiguchia, Barbara Sanz; Aiello, Iolinda; Crispini, Alessandra

doi: 10.1039/c5dt00817dpmid: 25904400

Historically, many useful drugs have been developed from natural sources and their mechanisms of action deeply investigated for therapeutic applications. Recently, the interaction between pharmacologically active biomolecules and transition metal ions has opened the way to the construction of new drugs, where the unique properties of metal complexes are combined with the specific mechanisms of action of the coordinated bioligands of natural extraction. In this context, this perspective summarizes some recent research studies devoted to the development of new metal-based drugs containing Zn(ii) or Cu(ii) metal ions. Both metals have a strong tendency to form highly stable complexes with N,N- and O,O-donor ligands bound through chelation, giving rise, particularly when the bound organic molecules are drug candidates of natural extraction, to drug delivery systems, new biologically active complexes and potential diagnostic agents due to their intrinsic spectroscopic properties.

Santos, Telma C.; Silva, Marta A.; Morgado, Leonor; Dantas, Joana M.; Salgueiro, Carlos A.

doi: 10.1039/c5dt00556fpmid: 25906375

Geobacter bacteria have a remarkable respiratory versatility that includes the dissimilatory reduction of insoluble metal oxides in natural habitats and electron transfer to electrode surfaces from which electricity can be harvested. In both cases, electrons need to be exported from the cell interior to the exterior via a mechanism designated as extracellular electron transfer (EET). Several c-type cytochromes from G. sulfurreducens (Gs) were identified as key players in this process. Biochemical and biophysical data have been obtained for ten Gs cytochromes, including inner-membrane associated (MacA), periplasmic (PpcA, PpcB, PpcC, PpcD, PpcE and GSU1996) and outer membrane-associated (OmcF, OmcS and OmcZ). The redox properties of these cytochromes have been determined, except for PpcC and GSU1996. In this perspective, the reduction potentials of these two cytochromes were determined by potentiometric redox titrations followed by visible spectroscopy. The data obtained are taken together with those available for other key cytochromes to present a thorough overview of the current knowledge of Gs EET mechanisms and provide a possible rationalization for the existence of several multiheme cytochromes involved in the same respiratory pathways.

Hayami, Shinya; Nakaya, Manabu; Ohmagari, Hitomi; Alao, Amolegbe Saliu; Nakamura, Masaaki; Ohtani, Ryo; Yamaguchi, Ryotaro; Kuroda-Sowa, Takayoshi; Clegg, Jack K.

doi: 10.1039/c4dt03743jpmid: 25599519

Two solvated cobalt(ii) terpyridine complexes, [Co(MeO-terpy)2](BF4)2·H2O (1·H2O) and [Co(MeO-terpy)2](BF4)2·acetone (1·acetone) were prepared. Annealing each of these complexes resulted in the formation of two desolvated species, 1 and 1′, respectively. 1·H2O and 1 exhibited two-step and gradual SCO. The compound 1·acetone has high-spin at all temperatures and 1′ undergoes a reverse spin transition due to a phase change.

Lee, Misun; Shin, Sung Min; Jeong, Nakcheol; Thallapally, Praveen K.

doi: 10.1039/c5dt01322dpmid: 25912165

Chiral metal–organic frameworks are considered a useful platform in heterogeneous catalysis for enantioselective chemical transformations. However, it has been observed that the enantioselectivity is sensitive to the site at which the reaction takes place, even in a single crystal, since the chiral environment of the catalytic site varies according to its location, e.g., that of the surface is anisotropic, whereas that of the interior is isotropic.