Radicals polyhydroxyl

In another version of this method, the radical generated by radical exchange from the aryl telluride carbohydrate 83 and the N-acetoxy-2-thiopyridone affords, after intramolecular cyclization and desulfanylation, the polyhydroxylated and phosphorylated pseudo sugar 84 [54] (Scheme 23). 

Cannabinidiol (CBND, 2.18) and cannabinol (2.19) are oxidation products of CBD and A9-THC formed by aromatization of the terpenoid ring. For the dehydrogenation of THC a radical mechanism including polyhydroxylated intermediates is suggested [10,11]. CBN is not the sole oxidation product of A9-THC. Our own studies at THC-Pharm on the stability of A9-THC have shown that only about 15% of lost A9-THC is recovered as CBN. 

Jeng US, Lin TL, Chang TS, Lee HY, Hsu CH, Hsieh YW, Canteenwala T, Chiang LY (2001) Comparison of the aggregation behavior of water-soluble hexa(sulfobutyl)fullerenes and polyhydroxylated fullerenes for their free-radical scavenging activity. Prog. Colloid Polym. Sci. 118 232-237. 

J. Marco-Contelles, C. Pozuelo, M. L. Jimeno, L. Martinez, and A. M. Grau, 6-exo Free radical cyclization of acyclic carbohydrate intermediates A new synthetic route to enantiomerically pure polyhydroxylated cyclohexane derivatives, J. Org. Chem. 57 2625 (1992). 

Oturan MA, Pinson J, Deprez D, Terlain B. Polyhydroxylation of salicylic acid by electrochemically generated OH radicals. New J Chem 1992 16 705-710. 

Marco-Contelles, J. et al. (5-Exo Free Radical Cyclizalion of Acyclic Carbohydrate Intermediates A New Synthetic Route to Enantiomerically Pure Polyhydroxylated Cyclohexane Derivatives. 3.1 1992 [144]... 

Oturan, M. A. and Pinson, 1. (1995) Hydroxylation by electrochemically generated OH radicals. Mono- and polyhydroxylation of benzoic acid Products and isomer distribution. 1. Phys. Chem. 99, 13948-13954. 

A diastereoselective formal addition of a 7ra i-2-(phenylthio)vmyl moiety to a-hydroxyhydrazones through a radical pathway is shown in Scheme 2.29. To overcome the lack of a viable intermolecular vinyl radical addition to C=N double bonds, not to mention a reaction proceeding with stereocontrol, this procedure employs a temporary silicon tether, which is used to hold the alkyne unit in place so that the vinyl radical addition could proceed intramolecularly. Thus, intermolecular addition of PhS" to the alkyne moiety in the chiral alkyne 161 leads to vinyl radical 163, which cyclizes in a 5-exo fashion, according to the Beckwith-Houk predictions, to give aminyl radical 164 with an a 7z-arrangement between the ether and the amino group. Radical reduction and removal of the silicon tether without prior isolation of the end product of the radical cyclization cascade, 165, yields the a-amino alcohol 162. This strategy, which could also be applied to the diastereoselective synthesis of polyhydroxylated amines (not shown), can be considered as synthetic equivalent of an acetaldehyde Mannich reaction with acyclic stereocontrol. 

The charge-transfer processes between chlorpromazine cation radicals (CPZ" -) and catecholamines were studied spectrochemically in order to determine the biological function of chlorpromazine (28]). Electrochemical oxidation of the neurotransmitter serotonin (SER, which carries a single phenolic group) produced polyhydroxylated compounds and the corresponding quinones (282) which are the most potent neurotoxins known. 

A number of aglycone flavonoids are potent inhibitors of in vitro oxidative modification of LDL [44]. Phenolic compounds isolated from red wine inhibit the copper-catalyzed oxidation of LDL in vitro (10 mmol/L), significantly more than a-tocopherol [45], possibly by regenerating a-tocopherol [44], Alternatively, chelation of divalent metal ions by flavonoids may reduce formation of free radicals induced by Fenton reactions [42]. Hydroxylation of the flavone nucleus appears to be advantageous because flavone itself is a poor inhibitor of LDL oxidation, whereas polyhydroxylated flavonoids such as quercetin, morin, hypoleatin, fisetin, gossypetin, and galangin are potent inhibitors of LDL oxidation [44],... 

Acrylic polyols are prepared by the free radical polymerisation of hydroxyethyl acrylate or methacrylate with other acrylic precursors. To introduce rigidity and stiffness into the polymer, the structure must be highly cross-linked. This is obtained by use of polyhydroxyl polyols (triol... 

We have explored in some detail the structure-reactivity relationships for vinyl- and allyl-ethers derived from polyhydroxylic compounds (mainly isopropylideneglycerol or ribose derivatives) for the free radical donor-acceptor copolymerization with diethyl fumarate (DEF) and diethyl maleate (DEM). Other allylojy and vinyloxy monomers with a more simple structure were also used as model compounds. The synthesis of non commercial but known monomers (ACG, AHE, AIG, HVE, VCG, VIG), as well as of the original pentose-based monomers (AIR, AR, ATMR, VIR, VTMR) was achieved by conventional laboratory methods, using appropriate catalysts and trying to minimize the use of solvents for chemical modification and for separation. 

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