title: Synthesis and antioxidant activity of hydroxylated phenanthrenes as cis-restricted resveratrol analogues.
abstract: Five hydroxylated phenanthrenes as "cis-configuration-fixed" resveratrol analogues differing in the number and position of the hydroxyl groups were designed and synthesized. Their antioxidant activity was studied by ferric reducing antioxidant power, 2,2-diphenyl-1-picrylhydrazyl free radical-scavenging, and DNA strand breakage-inhibiting assays, corresponding to their electron-donating, hydrogen-transfer and DNA-protecting abilities, respectively. In the above assays, their activity depends significantly on the number and position of the hydroxyl groups, and most of them are more effective than resveratrol. Noticeably, compound 9b (2,4,6-trihydroxyl phenanthrene) with the same hydroxyl group substitutions as resveratrol, is superior to the reference compound, highlighting the importance of extension of the conjugation over multiple aromatic-rings. Similar activity sequences were obtained in different experimental models, but the appreciable differences could contribute detailed insights into antioxidant mechanisms. Based on these results, the hydroxylated phenanthrenes may be considered as a novel type of resveratrol-directed antioxidants.
authors.affiliation: State Key Laboratory of Applied Organic Chemistry, Lanzhou University, Lanzhou, Gansu 730000, China.
authors.forename: De-Jun
authors.initials: DJ
authors.lastname: Ding
authors.forename: Xiao-Yan
authors.initials: XY
authors.lastname: Cao
authors.forename: Fang
authors.initials: F
authors.lastname: Dai
authors.forename: Xiu-Zhuang
authors.initials: XZ
authors.lastname: Li
authors.forename: Guo-Yun
authors.initials: GY
authors.lastname: Liu
authors.forename: Dong
authors.initials: D
authors.lastname: Lin
authors.forename: Xing
authors.initials: X
authors.lastname: Fu
authors.forename: Xiao-Ling
authors.initials: XL
authors.lastname: Jin
authors.forename: Bo
authors.initials: B
authors.lastname: Zhou
mesh_terms: D000975:Antioxidants / Q000138:chemical synthesis / Q000737:chemistry*; D006900:Hydroxylation; D015394:Molecular Structure; D010084:Oxidation-Reduction; D010616:Phenanthrenes / Q000737:chemistry*; D000077185:Resveratrol; D013237:Stereoisomerism; D013267:Stilbenes / Q000138:chemical synthesis / Q000737:chemistry*
chemical_list: D000975:Antioxidants; D010616:Phenanthrenes; D013267:Stilbenes; D000077185:Resveratrol