title: Sesquiterpene O-naphthoquinones from the root bark of Ulmus davidiana.
abstract: Three new sesquiterpene ortho-naphthoquinones, davidianones A, B and C, together with four known compounds, mansonones E, F, H and I, were isolated from the root bark of Ulmus davidiana. On the basis of spectral data including pulse field gradient two-dimensional NMR spectroscopy, the structures of new compounds were established as 3-hydroxymethyl-6,9-dimethylnaphtho(1,8-b,c)pyran-7,8-dione, 6-methoxycarbonyl-3,9-dimethylnaphtho(1,8-b,c)pyran-7,8-dione, 6-dimethoxymethyl-3,9-dimethylnaphtho(1.8-b,c)pyran-7,8-d ion e, respectively. Their antioxidative activities were evaluated by a thiobarbituric acid method using rat liver microsomes, with mansonone F showing the greatest activity.
authors.affiliation: Korea Research Institute of Bioscience and Biotechnology, Korea Institute of Science & Technology, Yusong, Taejon, Korea.
authors.forename: J P
authors.initials: JP
authors.lastname: Kim
authors.forename: W G
authors.initials: WG
authors.lastname: Kim
authors.forename: H
authors.initials: H
authors.lastname: Koshino
authors.forename: J
authors.initials: J
authors.lastname: Jung
authors.forename: I D
authors.initials: ID
authors.lastname: Yoo
mesh_terms: D000818:Animals; D000975:Antioxidants / Q000737:chemistry / Q000302:isolation & purification / Q000494:pharmacology*; D007723:Korea; D008862:Microsomes, Liver / Q000187:drug effects / Q000378:metabolism*; D015394:Molecular Structure; D009285:Naphthoquinones / Q000737:chemistry / Q000302:isolation & purification / Q000494:pharmacology*; D018517:Plant Roots; D010946:Plants, Medicinal; D051381:Rats; D012717:Sesquiterpenes / Q000737:chemistry / Q000302:isolation & purification / Q000494:pharmacology*; D013329:Structure-Activity Relationship; D017392:Thiobarbituric Acid Reactive Substances / Q000032:analysis; D014197:Trees
chemical_list: D000975:Antioxidants; D009285:Naphthoquinones; D012717:Sesquiterpenes; D017392:Thiobarbituric Acid Reactive Substances