Xyloketals,a new type of antioxidants from a marine mangrove fungus,have potential pharmacological properties.In this paper,the radical-scavenging activities of a series of synthetic xyloketals and related chromanes toward 2,2-diphenyl-1-picrylhydrazyl(DPPH)and 2,2′-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid)(ABTS)were evaluated by absorption spectrometry.One of the compounds(compound 10)displayed significant antioxidative action against DPPH and ABTS.A structure-activity analysis showed that the reactive sites on these compounds correlated with a hydroxygroup and also with ketal or aromatic H substituents.Based in part on a density functional theory(DFT)calculation of compound 10,the antioxidant mechanism of this chromane was deduced as a possible radical-scavenging mechanism by a sequential proton loss electron-transfer(SPLET)process.
Zhongliang XuBingtai LuQi XiangYiying LiShichang LiYongcheng LinJiyan Pang
