Record Details

Intramolecularly coordinated diorganyl ditellurides: Thiol peroxidase-like antioxidants

DSpace at IIT Bombay

View Archive Info
 
 
Field Value
 
Title Intramolecularly coordinated diorganyl ditellurides: Thiol peroxidase-like antioxidants
 
Creator MUGESH, G
PANDA, A
KUMAR, S
APTE, SD
SINGH, HB
BUTCHER, RJ
 
Subject chalcogenopyrylium trimethine dyes
active organoselenium compound
macrocyclic schiff-base
x-ray structure
glutathione-peroxidase
photodynamic therapy
chalcogenapyrylium dyes
lipid-peroxidation
singlet-oxygen
photochemotherapeutic agents
 
Description A series of diaryl ditellurides with and without coordinating amino/imino groups are synthesized by using either the Grignard route or the heteroatom-directed aromatic lithiation route. The chiral ditelluride (R),(R)-bis[2-(4-ethyl-2-oxazolinyl)phenyl] ditelluride is synthesized in an enantiomerically pure form by stereoselective ortho-lithiation. The thiol peroxidase activity of the ditellurides is studied by using H2O2 as a substrate and PhSH as a cosubstrate. The initial rates for the reduction of H2O2 catalyzed by diaryl ditellurides are much higher than those catalyzed by the corresponding diselenides. A comparison of the activities between various diorganyl ditellurides and diselenides shows that the presence of basic amino groups in the close proximity of tellurium enhances the reduction rates and the effect of amino groups on the activity is more pronounced in the case of ditellurides as compared to the corresponding diselenides. On the other hand, a correlation between the strength of Te...N intramolecular interactions and thiol peroxidase activity reveals that the strong Te...N interactions reduce the thiol peroxidase activity of amino/imino-substituted ditellurides. A plot of Te...N distances against Te-125 NMR chemical shifts shows a linear correlation.
 
Publisher AMER CHEMICAL SOC
 
Date 2011-07-14T09:13:05Z
2011-12-26T12:48:18Z
2011-12-27T05:48:30Z
2011-07-14T09:13:05Z
2011-12-26T12:48:18Z
2011-12-27T05:48:30Z
2002
 
Type Article
 
Identifier ORGANOMETALLICS, 21(5), 884-892
0276-7333
http://dx.doi.org/10.1021/om010759z
http://dspace.library.iitb.ac.in/xmlui/handle/10054/3917
http://hdl.handle.net/10054/3917
 
Language en