A glyceride containing three ferulic groups was first synthesized in order to investigate intermolecular synergistic antioxidant activity. The antioxidant activity was evaluated via a radical-scavenging reaction of D...A glyceride containing three ferulic groups was first synthesized in order to investigate intermolecular synergistic antioxidant activity. The antioxidant activity was evaluated via a radical-scavenging reaction of DPPH˙ radical. Although the scavenging capacities of both antioxidants, ferulic acid and glyceride tri-ferulate, were roughly equal, the apparent activation energy(Ea) of 19.50 kJ/mol for glyceride tri-ferulate is obviously lower than that of 28.80 kJ/mol for ferulic acid. The synergistic effect on Ea was further explained by a parallel π-π-stacking interaction.展开更多
L-Tyr-EMPO,a new EMPO analogue bearing an L-tyrosine methyl ether group,was first synthesized by acylation.Various radicals,including O-·2,·OH,·OR,and ·R,have been efficiently detected and characte...L-Tyr-EMPO,a new EMPO analogue bearing an L-tyrosine methyl ether group,was first synthesized by acylation.Various radicals,including O-·2,·OH,·OR,and ·R,have been efficiently detected and characterized via L-Tyr-EMPO.The half-life of the L-Tyr-EMPO superoxide adduct was estimated to be ca.6.5 min.More importantly,the present study demonstrated a new synthetic strategy for covalent conjugation between cyclic-nitrone and amino group in peptides or proteins,by which the site-specifically spin trapping can be performed via antibody linked nitrone in the near future.Furthermore,with the help of the covalent link,the targeting for the areas of interest in which the monitored radical species was sitespecially generated.展开更多
Six linear nitrones,three DBN derivatives and their phosphoryl analogues,were first synthesized in this article,and the structures of their O-·2-spin trapping products,the nitroxides,were theoretically and experi...Six linear nitrones,three DBN derivatives and their phosphoryl analogues,were first synthesized in this article,and the structures of their O-·2-spin trapping products,the nitroxides,were theoretically and experimentally analyzed.The theoretical calculations on the optimized geometries of the spin adducts,using DFT method at B3LYP/6-311+G(d,p)//B3LYP/6-31G(d) level,demonstrated that both the intromolecular H-bonds and their internal rotations around C—N bond are the key factors for stabilizing the spin adducts.展开更多
文摘A glyceride containing three ferulic groups was first synthesized in order to investigate intermolecular synergistic antioxidant activity. The antioxidant activity was evaluated via a radical-scavenging reaction of DPPH˙ radical. Although the scavenging capacities of both antioxidants, ferulic acid and glyceride tri-ferulate, were roughly equal, the apparent activation energy(Ea) of 19.50 kJ/mol for glyceride tri-ferulate is obviously lower than that of 28.80 kJ/mol for ferulic acid. The synergistic effect on Ea was further explained by a parallel π-π-stacking interaction.
基金supported by the National Natural Science Foundation of China(21465021,21463023)Key Project of Ministry of Education,China(211189)+1 种基金Natural Science Foundation of Gansu Province,China(1208RJZE139)Program of Gansu Provincial University for Leaders of Disciplines in Science,China(11zx-04)~~
文摘L-Tyr-EMPO,a new EMPO analogue bearing an L-tyrosine methyl ether group,was first synthesized by acylation.Various radicals,including O-·2,·OH,·OR,and ·R,have been efficiently detected and characterized via L-Tyr-EMPO.The half-life of the L-Tyr-EMPO superoxide adduct was estimated to be ca.6.5 min.More importantly,the present study demonstrated a new synthetic strategy for covalent conjugation between cyclic-nitrone and amino group in peptides or proteins,by which the site-specifically spin trapping can be performed via antibody linked nitrone in the near future.Furthermore,with the help of the covalent link,the targeting for the areas of interest in which the monitored radical species was sitespecially generated.
文摘Six linear nitrones,three DBN derivatives and their phosphoryl analogues,were first synthesized in this article,and the structures of their O-·2-spin trapping products,the nitroxides,were theoretically and experimentally analyzed.The theoretical calculations on the optimized geometries of the spin adducts,using DFT method at B3LYP/6-311+G(d,p)//B3LYP/6-31G(d) level,demonstrated that both the intromolecular H-bonds and their internal rotations around C—N bond are the key factors for stabilizing the spin adducts.
