Plant-derived polyphenolic compounds have received much attention for their ability to sequester high-energy free radicals in a great variety of food-related and biological systems, protecting those systems from oxidative change. The ability of these compounds to scavenge free radicals has always been attributed to their phenolic functionality, from which a hydrogen atom can be easily abstracted. In this study, the cinnamates and the ubiquitous hydroxycinnamates were found to equally suppress the formation of oxidation products in wine exposed to the Fenton reaction (catalytic Fe(II) with hydrogen peroxide). Mechanistic investigations led to the unexpected discovery that the α,β-unsaturated side chain of cinnamic acids could efficiently trap 1-hydroxyethyl radicals, representing a newly discovered mode of antioxidant radical scavenging activity for these broadly occurring compounds in a food system. The proposed pathway is supported by prior fundamental studies with radiolytically generated radicals.

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Closure OTR strongly affects sulfur dioxide levels - the primary antioxidant in wine - in aged wine, but phenolic levels substantially alter the secondary reactions of oxidative aging.

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Condensation of 2,4‐bis(trimethylsilyloxy)pyridine (1) with 2,3,5‐tri‐O‐benzoyl‐D‐ribofuranosyl bromide (2) gave 4‐hydroxy‐1‐(2,3,5‐tri‐O‐benzoyl‐β‐D‐ribofuranosyl)‐2‐pyridone (3). Deblocking of 3 gave 4‐hydroxy‐1‐β‐D‐ribofuranosyl‐2‐pyridone (3′‐deazauridine) (4). Treatment of 4 with acetone and acid gave 2′,3′‐O‐isopropylidene‐3‐deazauridine (6). Reaction of 4 with diphenylcarbonate gave 2‐hydroxy‐1‐β‐D‐arabinofuranosyl‐4‐pyridone‐O2←2′‐cyclonucleoside (7) which established the point of gylcosidation and configuration of 4. Base‐catalyzed hydrolysis of 7 gave 4‐hydroxy‐1‐β‐D‐arabinofuranosyl‐2‐pyridone (3‐deazauracil arabinoside) (12). Fusion of 1 with 3,5‐di‐O‐p‐toluyl‐2‐deoxy‐D‐erythro‐pentofuranosyl chloride (5) gave the blocked anomeric deoxynucleosides 8 and 10 which were saponified to give 4‐hydroxy‐1‐(2‐deoxy‐β‐D‐erythro‐pentofuranosyl)‐2‐pyridone (2′‐deoxy‐3‐deazauridine) (11) and its α anomer (9). Condensation of 4‐acetamido‐2‐methoxypridine (13) with 2 gave 4‐acetamido‐1‐(2,3,5‐tri‐O‐benzoyl‐β‐D‐ribofuranosyl)‐2‐pyridone (14) which was treated with alcoholic ammonia to yield 4‐acetamido‐1‐β‐D‐ribofuranosyl‐2‐pyridone (15) or with methanolic sodium methoxide to yield 4‐amino‐1‐β‐D‐ribofuranosyl‐2‐pyridone (3‐deazacytidine) (16). Condensation of 13 and 2,3,5‐tri‐O‐benzyl‐D‐arabinofuranosyl chloride (17) gave the blocked nucleoside 22 which was treated with base and then hydrogenolyzed to give 4‐amino‐1‐β‐D‐arabinofuranosyl‐2‐pyridone (3‐deazacytosine arabinoside) (23). Fusion of 13 with 5 gave the blocked anomeric deoxynucleosides 18 and 20 which were deblocked with methanolic sodium methoxide to yield 4‐amino‐1‐(2‐deoxy‐β‐D‐erythro‐pentofuranosyl)‐2‐pyridone (2′‐deoxy‐3‐deazacytidine) (21) and its a anomer 19. The 2′‐deoxy‐erythro‐pentofuranosides of both 3‐deazauracil and 3‐deazacytosine failed to obey Hudson's isorotation rule but did follow the “quartet”‐“triplet” anomeric proton splitting pattern in the 1H nmr spectra.