Autooxidation of

Chemiluminescence is also obtained by anionic autooxidation of (41) with oxygen ia alkaline dimethyl sulfoxide (DMSO) (216). Qc has been reported to be 10% and ketone (43) and CO2 are obtained. Several analogues of luciferin have been prepared that are also chemiluminescent when they react with oxygen ia alkaline DMSO (62). 

Photochemical autooxidation of ketones, 316 Photochemical a-cleavage, 296 Photochemical cleavage of bonds attaching atoms to the a-carbon of ketones, 307 Photochemical cleavage of exocyclic. S-bonds, 323... 

Cholesterol autooxidation can occur. Not much information is available on autooxidation of cholesterol in liposomes (Lichtenberg and Barenholz, 1988). 

It has also been observed " that sulphosalicylic acid strongly catalyses autooxidation of Fe(II) at pH 6. A complex of the chelate, Fe(II) and molecular oxygen is believed to be formed and to break down. Ethylenediaminetetraacetic and its analogues behave similarly . 

Autooxidation of 1,1-DimethyIhydra-zine, NAVEWEPS Report 8798, NOTS Technical Publication 3903, September 1965. 

Stone, D. A. "The Vapor Phase Autooxidation of Unsymmetrical DimethyIhydrazine and 50 Percent Unsymmetrical Dimethyl-hydrazine-50 Percent Hydrazine Mixtures," Report No. ESL-TR-80-21, April 1980. 

Esterbauer et al. (1991) have demonstrated that /3-carotene becomes an effective antioxidant after the depletion of vitamin E. Our studies of LDL isolated from matched rheumatoid serum and synovial fluid demonstrate a depletion of /8-carotene (Section 2.2.2.2). Oncley et al. (1952) stated that the progressive changes in the absorption spectra of LDL were correlated with the autooxidation of constituent fatty acids, the auto-oxidation being the most likely cause of carotenoid degradation. The observation that /3-carotene levels in synovial fluid LDL are lower than those of matched plasma LDL (Section 2.2.2) is interesting in that /3-carotene functions as the most effective antioxidant under conditions of low fOi (Burton and Traber, 1990). As discussed above (Section 2.1.3), the rheumatoid joint is both hypoxic and acidotic. We have also found that the concentration of vitamin E is markedly diminished in synovial fluid from inflamed joints when compared to matched plasma samples (Fairburn etal., 1992). This difference could not be accounted for by the lower concentrations of lipids and lipoproteins within synovial fluid. The low levels of both vitamin E and /3-carotene in rheumatoid synovial fluid are consistent with the consumption of lipid-soluble antioxidants within the arthritic joint due to their role in terminating the process of lipid peroxidation (Fairburn et al., 1992). 

Kim, JS, E Nara, H Kobayashi, J Terao, and A Nagao. 2001. Formation of cleavage products by autooxidation of lycopene. Lipids 36(2) 191—199. 

Zhang, H, E Kotake-Nara, H Ono, and A Nagao. 2003. A novel cleavage product formed by autooxidation of lycopene induces apoptosis in HL-60 cells. Free Radic Biol Med 35(12) 1653-1663. 

John, G. and Pillai, C.K.S. (1993) Synthesis and characterization of a self-crosslinkable polymer from cardanol autooxidation of poly(cardanyl acrylate) to crosslinked film. Journal of Polymer Science Part A Polymer Chemistry, 31, 1069-1073. 

Witkop and Goodwyn reported (288) that ozonolysis of yohimbine (74) and its derivatives led to the corresponding quinolone derivatives. This reaction has been thoroughly investigated by Winterfeldt (289). For example, autooxidation of lactam 347 resulted in quinolone 599, which upon treatment with phosphoryl chloride, followed by catalytic reduction, gave pyrrolo[3,4-h]quioline derivative 600 (290). This transformation was also used as a key step in the biomimetic synthesis of camptothecin (601), performed by Winterfeldt et al. (291, 292). 

An interesting process of C-C bond formation is represented by the autooxidation of Mercurialis perennis L. plant alkaloid hermidin. The reaction proceeds through the formation of a transient blue anion-radical, which dimerizes with the transfer of the reaction center to give, eventually, chryso-hermidin as a dimeric hexaketone (Wasserman et al. 1993 Scheme 7.59). 

The interaction of dioxygen has been observed in several systems, mostly due to autooxidation of ferrous hemes with dioxygen, but only characterized in a few instances. Sakamoto et al. (119) have illustrated peroxidase-type activity using a helix-disulfide-helix system that binds a single heme as shown in Fig. 13. The initial communication illustrated that the addition of an organic cosolvent, trifiuoroethanol, increases the helical content of the peptide, the affinity for heme (1.7 DM IQ at maximal affinity, 15% TFE), and the peroxidase activity (conversion of... 

Information on the formation and decomposition of iron(III)-sulfur(IV) complexes, in the presence and absence of dioxygen, is vital to the understanding of iron-catalyzed autooxidation of sulfur(IV). The kinetics and mechanism of formation of mono-, bis-, and tris-sulfito-iron(III) from Fe " aq/FeOH aq, have been established, together with estimates of their stability... 

Figure 1. Representative polarographic traces that depict inhibition by energy transfer inhibitors and allelochemicals of ADP-stimulated electron transport in isolated spinach thylakoids and circumvention of the inhibition by an uncoupler (FCCP, 2 pM). Trace A chlorotributyltin (TBT, 1 pM) trace B phlorizin (400 pM) trace C DCCD (20 pM) trace D quercetin (200 pM) trace E naringenin (1 mM). Water served as electron donor and methyl viologen as electron acceptor. Rates of oxygen utilization, that resulted from the autooxidation of methyl viologen, expressed as pmol 0 consumed/mg Chi h, are indicated parenthet ically.

These molecules are made by the autooxidation of cumene (what s that ), which is made by alkylation (what s that ) of propylene and benzene. 

Figure 10-5 Reaction steps to make acetone and phenol by autooxidation of isopropyl benzene (also called cumene).

Figure 10-6 Reaction steps to make adipic add by autooxidation of cyclohexane. Adipic add is a key ingredient in Nylon.

Hydrogen peroxide is commercially produced by autooxidation of ethyl anthraquinol in a solvent such as toluene or ethylbenzene. The product ethyl anthraquinone is reduced by hydrogen over supported nickel or platinum catalyst to regenerate hack the starting material, ethyl anthraquinol for a continuous production of H2O2. The reaction steps are ... 

Upon irradiation of fats, the formation of a multitude of products is possible after primary ionization and excitation, and deprotonation followed by various dimerization, disproportionation reactions, dissociations, or decarboxylation. It is generally assumed that irradiation in the presence of oxygen leads to accelerated autooxidation of lipids, and that the pathways are the same as in light-induced or metal-catalyzed autooxidation. 

Brandt, C., I. Fabian, and R. van Eldik, Kinetics and Mechanism of the Iron(III)-Catalyzed Autooxidation of SulfuKIV) Oxides in Aqueous Solution—Evidence for the Redox Cycling of Iron in the Presence of Oxygen and Modeling of the Overall Reaction Mechanism, Inorg. Chem., 33, 687-701 (1994). 

Hoffmann, M. R., and S. D. Boyce, Catalytic Autooxidation of Aqueous Sulfur Dioxide in Relationship to Atmospheric Systems, Adr. Environ. Sci. Technol., 12, 147-189(1983). 

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