Cellular oxidative stress has been implicated as a key mechanism of cell differentiation provoked by several compounds (doxorubicins, fibrades, edelfosine). Phenylacetate and its derivatives in submillimolar to millimolar concentrations induce cell differentiation. Ion-exclusion chromatography is widely used for separation and analysis of weak acids. We applied it to the analysis of phenylaceti...

Seasonal dependence of peroxy radical concentrations at a northern hemisphere marine boundary layer site during summer and winter: evidence for photochemical activity in winter Z. L. Fleming, P. S. Monks, A. R. Rickard, B. J. Bandy, N. Brough, T. J. Green, C. E. Reeves, and S. A. Penkett Department of Chemistry, University of Leicester, Leicester, UK School of Environmental Sciences, University...

Cavity ringdown spectra of the near IR Ã2A′ − X̃2A′′ electronic transition of acetyl peroxy radical and its perdeutero analogue are reported. The electronic origin for the CH3C(O)O2 is observed at 5582.5(5) cm−1. Extensive ab initio calculations have been carried out to predict frequencies and help assign the electronic origin, observed vibrational hot bands and several à state vibrational frequ...

The radical anion of dioxygen superoxide (O2.-) is a physiological free radical formed in various enzymatic processes. On the one hand superoxide is a precursor of reactive oxygen and nitrogen species (hydroxyl radicals, peroxy radicals, hydrogen peroxide, peroxynitrite, etc.), -the initiators of cellular damage; on the other hand it is a signaling molecule regulating numerous physiological pro...

Radiation-induced functionalization of ferroelectric poly(vinylidene fluoride) was studied by ESR spectroscopy. The samples were irradiated in the high vacuum of a Van de Graaff accelerator with 1.0 MeV and 1.5 MeV electrons at room temperature and the decay of free radicals was studied after transferring the samples into the air. The samples exhibit a multicomponent ESR spectrum that can be de...

Kinetics of enzymic oxidation of indoleacetic acid (ISA) are interpreted as indicating that the reaction has an autocatalytic, cyclical mechanism invol\-ing unst,ablc intermcdiatcs whose formation and disappearance are important in determining the over-all reaction rate. The kinetics do not supporl the idea that IAA oxidation occurs mainly by reaction with Mnt3, nor that the reaction is an elec...

This paper reviews recent investigations by Slater and colleagues into the metabolic activation of halogenated alkanes in general and carbon tetrachloride in particular. It is becoming increasingly accepted that free radical intermediates are involved in the toxicity of many such compounds through mechanisms including lipid peroxidation, covalent binding, and cofactor depletion. Here we describ...

CBS-QB3 calculations have been used to determine thermochemical and kinetic parameters of the isomerisation and decomposition reactions of the acetonylperoxy radical, CH3C(O)CH2OO* , which has been formed via the reaction of acetonyl radical with O2 leading to the formation of an energised peroxy adduct with a calculated well depth of near 111 kJ mol(-1). This species can undergo subsequent 1,5...

The α,ω-dialkoxyfluoropolyethers (DA-FPEs) characterized by the structure RHO(CF2CF2O)n(CF2O)mRH have been developed as a new class of environmentally friendly hydrofluoroethers (HFEs) suitable as solvents, long-term refrigerants, cleaning fluids, and heat transfer fluids. Synthetic methodologies for DA-FPEs described here consist of radical-initiated oxypolymerization of olefin, peroxy-elimina...

An efficient amidation method between readily available 1,1-dicyanoalkanes and either chiral or nonchiral amines was realized simply with molecular oxygen and a carbonate base. This oxidative protocol can be applied to both sterically and electronically challenging substrates in a highly chemoselective, practical, and rapid manner. The use of cyclopropyl and thioether substrates support the rad...