Special Issue "Selenium and Tellurium Chemistry"

Guest Editor
Dr. Rudolf Pietschnig
Karl-Franzens-Universität, Institut für Chemie, Anorganische Chemie, Schubertstrasse 1, A-8010 Graz, Austria
E-Mail:

selenium, tellurium, chalcogene, organoselenium, organotellurium, selenoproteins, selenium-enrichment, selenium speciation, selenium bioavailability, toxicology, selenide, telluride, selenite, tellurite, heterocycles, gas phase deposition, CVD, molecular magnets, materials, 77Se nmr, chalcogen clusters, chalcogen ions, crystal structures

Title: Role of Selenium in Vascular Health and Disease
Authors: Lorraine M. Sordillo*, Chris M. Corl, and Stacey L. Aitken
*Corresponding author: Lorraine M. Sordillo, College of Veterinary Medicine, Michigan State University, East Lansing, MI 48824
E-mail: sordillo@msu.edu
Abstract: Selenium is an essential trace element that is known to play a beneficial role in both human and animal health. Considerable epidemiologic data exists to support the concept that various forms of selenium can protect against many types of cancers, cardiovascular diseases, and several other inflammatory-based diseases. The metabolism of selenium in mammals is determined largely by the dietary sources (organic or inorganic) and most of the protective effects of selenium are postulated to be due to either its metabolism into methylated selenocompounds or its incorporation into selenoproteins. Endothelial cell dysfunction is linked with the development of many diseases and one way that selenium may influence health is by the ability to maintain vascular homeostasis. This review will describe the potential molecular mechanisms of how selenocompounds and selenoproteins can impact vascular function and mammalian health.

Manuscript ID: molecules-selenium-20081028-jp-Sugimoto
Type of paper: Review
Tentative title: Selenium-Substituted Ethylenedithiotetrathiafulvalenothioquinone-1,3-dithiolemethide Donor Molecules
Authors: Toyonari Sugimoto *, Toshiki Hayashi, Xunwen Xiao, Yuhta Yamaji and Xiangfeng Shao
Affiliation: Department of Chemistry, Graduate School of Science,
Osaka Prefecture University
Abstract: Ethylenedithiotetrathiafulvalenothioquinone-1,3-dithiolemethide and its quinone derivative are such useful donor molecules that their charge-transfer (CT) salts with magnetic FeX4- (X = Cl, Br) ions give one ferromagnetic molecular semiconductor and four antiferromagnetic molecular metals with significant p-d interaction between conducting p electrons and localized d spins. A selenium atom has a larger van der Waals radius than oxygen and sulfur atoms, so selenium-substituted derivatives of the thioquinone and quinone donor molecules are expected to bring about much more stabilization of metallic state as well as stronger p-d interaction, by which an unprecedented ferromagnetic molecular metal working at reasonable temperatures could be realized. The sulfur atoms at different positions of the thioquinone donor molecule are substituted with selenium atoms using newly-developed synthetic methods to give new donor molecules with an ethylenediselena group in place of an ethylenedithio group, with a selenone group in place of a thione group, with 1,3-diselenole group in place of a 1,3-dithiole group and with selenium atoms in place of some of four sulfur atoms in a central tetrathiaethylene group, respectively. This review summarizes molecular structures and pysical properties of thses selenium donor molecules, and also crystal structures and electrical conducting/magnetic properties of their CT salts with FeX4- ions.

Manuscript ID: molecules-selchem-20081103-cy-Odysseos
Type of Paper: Review
Title: Selenium in Cancer Prevention and Therapeutics: One Element, many Targets
Author: Andreani D.Odysseos
Affiliation: EPOS-Iasis, R&D, Nicosia, Cyprus
E-mail: andreani@epos-iasis.com
Abstract: The past decade has experienced the evolution of a promising group of selective agents comprised of organic Selenium compounds. Eventhough the critical Se metabolite hypothesis has steadily gained both in vivo and in vitro support, much remains debatable as to what mechanisms account for the cancer preventive activity of Selenium. This review highlights the propensities of these agents to modulate critical signals and affect selectively a multitude of molecular targets in premalignant and malignant lesions. It further provides an insight into how modifications of their structural characteristics may alter dramatically their biological activities due to the evolution of signal-generating active intermediates and metabolites. Mechanisms address key elements such as the organ site specificity, the selectivity against transformed phenotype, the forms and effective doses of Se and the responsive carcinogenesis stages and molecular targets.

Manuscript ID: molecules-selchem-20081227-jp-Hada
Type of Paper: Article
Title: Excitation and Circular Dichroism Spectra of (+)-(S,S)-bis(2-methylbutyl)chalcogenide: SAC and SAC-CI calculations
Authors: Yasushi Honda and Masahiko Hada
Affiliations: Department of Chemistry, Graduate School of Science and Engineering, Tokyo Metropolitan University
E-mail: hada@tmu.ac.jp
Abstract: Theoretical electronic spectra and natural circular dichroism (CD) spectra of (+)-(S,S)-bis(2-methylbutyl)chalcogenide, Ch[CH2CH(CH3)C2H5]2 (Ch = S, Se, Te), were calculated by the symmetry adapted cluster (SAC) and SAC-configuration interaction (SAC-CI) methods. Whereas the calculated CD spectrum for each stable conformation itself did not reproduce the corresponding experimental one, their Boltzmann-averaged spectra showed good agreement with the experimental results. We provided the assignment for each spectral band according to our calculation results. For the telluride compound, temperature dependence of the CD spectra were experimentally observed due to variation in the Boltzmann factor, and our calculations reproduced it qualitatively. The features that we could not reproduced in the temperature dependence might be attributed to triplet transitions through the spin-orbit interaction effects at present, but further investigations are necessary for conclusive discussions.