title: Antioxidant lignoids from leaves of Ribes nigrum.
abstract: Phytochemical investigation of the leaves of Ribes nigrum resulted in the isolation of fourteen compounds, including four 7,7'-epoxylignans, three tetrahydrofuran-type sesquilignans, and a spirocyclic dilignan. Their structures were elucidated by extensive spectroscopic analyses and by chemical transformations. The isolated compounds were evaluated for their antioxidant activities using superoxide anion scavenging assay and DPPH free radical scavenging assay. Ribesin D and ribesin G showed the most potent superoxide anion scavenging activity with EC50 values of 1.24 and 1.12 μM, respectively, and the structure-activity relationship was discussed.
authors: Faculty of Pharmaceutical Sciences, Toho University, Miyama 2-2-1, Funabashi, Chiba 274-8510, Japan.
authors: Tatsunori
authors: T
authors: Sasaki
authors: Wei
authors: W
authors: Li
authors: Shinnosuke
authors: S
authors: Zaike
authors: Yoshihisa
authors: Y
authors: Asada
authors: Qin
authors: Q
authors: Li
authors: Fenghua
authors: F
authors: Ma
authors: Qingbo
authors: Q
authors: Zhang
authors: Kazuo
authors: K
authors: Koike
mesh_terms: D000975:Antioxidants / Q000737:chemistry / Q000302:isolation & purification / Q000494:pharmacology*; D001713:Biphenyl Compounds / Q000378:metabolism; D005663:Furans / Q000737:chemistry / Q000302:isolation & purification / Q000494:pharmacology*; D017705:Lignans / Q000737:chemistry / Q000302:isolation & purification / Q000494:pharmacology*; D015394:Molecular Structure; D010851:Picrates / Q000378:metabolism; D010936:Plant Extracts / Q000737:chemistry / Q000494:pharmacology*; D018515:Plant Leaves / Q000737:chemistry; D031965:Ribes / Q000737:chemistry*; D013329:Structure-Activity Relationship; D013481:Superoxides / Q000378:metabolism*
chemical_list: D000975:Antioxidants; D001713:Biphenyl Compounds; D005663:Furans; D017705:Lignans; D010851:Picrates; D010936:Plant Extracts; C588388:ribesin D; C588389:ribesin G; D013481:Superoxides; C004931:1,1-diphenyl-2-picrylhydrazyl
keywords: Antioxidant activity; Dilignan; Grossulariaceae; Lignan; Ribes nigrum; Sesquilignan