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RADIATION CHEMISTRY AND PHYSICS, RADIATION TECHNOLOGIES
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COMPUTATIONAL STUDY ON THE 1,2-HYDROGEN SHIFT
IN THIYL, OXYL, AMINYL AND AMIDYL RADICALS
Dariusz Pogocki, Monika Celuch, Arvi Rauk 1/
1/
Department of Chemistry, University of Calgary, Canada
The central issue of this paper are the reactions of
the 1,2-hydrogen shift from the carbon atom to the
adjacent heteroatom in thiyl, oxyl, aminyl and
amidyl radicals. From the physiological point of
view, thiols are one of the most important classes
of sulphur-containing compound. The protective
or antioxidant effects of thiols result from the fact
that they can act as hydrogen or electron donors
(pH dependent). One electron oxidation of thiols
Table. G3MP2B3 calculated free energies [kcal mol –1 ].
leads to the formation of thiyl radicals RCH 2 S • .
Therefore, RCH 2 S • are important intermediates
in biological conditions of oxidative stress [1]. They
are moderately good oxidants, having potential to
abstract “activated” hydrogen from carbon atoms.
This ability has been already experimentally demonstrated
for several groups of biologically important
compounds such as alcohols [2], carbohydrates
[3], fatty acids [4-7], amino acids [8], and peptides