title: Antioxidant lignans and chromone glycosides from Eurya japonica.
abstract: Four new 8,8',7,2'-lignans, (+)-ovafolinin B-9'-O-β-d-glucopyranoside (1), (-)-ovafolinin B-9'-O-β-d-glucopyranoside (2), (+)-ovafolinin E-9'-O-β-d-glucopyranoside (3), and (-)-ovafolinin E-9'-O-β-d-glucopyranoside (4), two neolignans, eusiderin N (5) and (7S,8R)-3,5,5'-trimethoxy-4',7-epoxy-8,3'-neolignan-9,9'-diol-4-O-β-d-xylopyranoside (6), and two new chromone glycosides, 5,7-dihydroxy-4H-chromen-4-one-3-O-β-d-glucopyranoside (7) and 5,7-dihydroxy-4H-chromen-4-one-3-O-β-d-xylopyranoside (8), together with 25 known compounds, were isolated from the stems of Eurya japonica. Structural elucidation of compounds 1-8 was established by spectroscopic methods, especially 2D NMR techniques, electronic circular dichroism data, and comparison with reported data. The isolates were evaluated for antioxidant and anti-NO production activities. Compounds 1, 2, 12-20, and 29 (ED50 23.40 μM for 1) demonstrated potent antioxidant activity compared to the positive control α-tocopherol (ED50 27.21 μM). On the other hand, compounds 1, 2, 7-9, 12-20, and 32 showed only weak anti-NO production activity when compared to the positive control quercetin.
authors.affiliation: National Research Institute of Chinese Medicine, Taipei 112, Taiwan, Republic of China.
authors.forename: Li-Ming
authors.initials: LM
authors.lastname: Yang Kuo
authors.forename: Li-Jie
authors.initials: LJ
authors.lastname: Zhang
authors.forename: Hung-Tse
authors.initials: HT
authors.lastname: Huang
authors.forename: Zhi-Hu
authors.initials: ZH
authors.lastname: Lin
authors.forename: Chia-Ching
authors.initials: CC
authors.lastname: Liaw
authors.forename: Hui-Ling
authors.initials: HL
authors.lastname: Cheng
authors.forename: Kuo-Hsiung
authors.initials: KH
authors.lastname: Lee
authors.forename: Susan L
authors.initials: SL
authors.lastname: Morris-Natschke
authors.forename: Yao-Haur
authors.initials: YH
authors.lastname: Kuo
authors.forename: Hsiu-O
authors.initials: HO
authors.lastname: Ho
mesh_terms: D000975:Antioxidants / Q000737:chemistry / Q000302:isolation & purification* / Q000494:pharmacology*; D001713:Biphenyl Compounds / Q000494:pharmacology; D002867:Chromones / Q000737:chemistry / Q000302:isolation & purification* / Q000494:pharmacology*; D006027:Glycosides / Q000737:chemistry / Q000302:isolation & purification* / Q000494:pharmacology*; D017705:Lignans / Q000737:chemistry / Q000302:isolation & purification* / Q000494:pharmacology*; D015394:Molecular Structure; D009569:Nitric Oxide / Q000096:biosynthesis; D019906:Nuclear Magnetic Resonance, Biomolecular; D010851:Picrates / Q000494:pharmacology; D018547:Plant Stems / Q000737:chemistry; D011794:Quercetin / Q000494:pharmacology; D013237:Stereoisomerism; D013624:Taiwan; D028242:Theaceae / Q000737:chemistry*; D024502:alpha-Tocopherol / Q000494:pharmacology
chemical_list: D000975:Antioxidants; D001713:Biphenyl Compounds; D002867:Chromones; D006027:Glycosides; D017705:Lignans; D010851:Picrates; D009569:Nitric Oxide; D011794:Quercetin; C004931:1,1-diphenyl-2-picrylhydrazyl; D024502:alpha-Tocopherol