title: Quiquelignan A-H, eight new lignoids from the rattan palm Calamus quiquesetinervius and their antiradical, anti-inflammatory and antiplatelet aggregation activities.
abstract: Eight new lignin derivatives, termed quiquelignan A-H (1-8), comprising three tricin-type flavonolignans (1-3) and five 8-O-4' neolignans (4-8), were isolated from the ethanol extract of Calamus quiquesetinervius stems. Structural elucidation of the new isolates was accomplished on the basis of spectroscopic data. Compounds 1-8 showed strong-to-moderate antioxidant activity against the hydroxy radical (()OH). Among them, compound 5 showed significantly higher hydroxy radical scavenging activity (IC(50) 4.4microg/mL). Compounds 2-4 and 6-8 dose-dependently suppressed the LPS-stimulated production of nitric oxide (NO) in RAW 264.7 cells. The anti-inflammatory potency of 4 and 6 was 2.7-4.5-fold higher compared with quercetin. Compounds 2-4, 6 and 8 also exhibited mild collagen-antagonistic activity, but were inactive with respect to thrombin-induced platelet aggregation.
authors.affiliation: Graduate Institute of Natural Products, Kaohsiung Medical University 807, Taiwan, ROC.
authors.forename: Chao-Lin
authors.initials: CL
authors.lastname: Chang
authors.forename: Li-Jie
authors.initials: LJ
authors.lastname: Zhang
authors.forename: Ru-Yin
authors.initials: RY
authors.lastname: Chen
authors.forename: Chin-Chung
authors.initials: CC
authors.lastname: Wu
authors.forename: Hui-Chi
authors.initials: HC
authors.lastname: Huang
authors.forename: Michael C
authors.initials: MC
authors.lastname: Roy
authors.forename: Jhih-Ping
authors.initials: JP
authors.lastname: Huang
authors.forename: Yang-Chang
authors.initials: YC
authors.lastname: Wu
authors.forename: Yao-Haur
authors.initials: YH
authors.lastname: Kuo
mesh_terms: D000818:Animals; D000893:Anti-Inflammatory Agents / Q000737:chemistry / Q000302:isolation & purification / Q000494:pharmacology*; D000975:Antioxidants / Q000737:chemistry / Q000302:isolation & purification / Q000494:pharmacology*; D031081:Calamus / Q000737:chemistry*; D002470:Cell Survival / Q000187:drug effects; D004305:Dose-Response Relationship, Drug; D016166:Free Radical Scavengers / Q000737:chemistry / Q000302:isolation & purification / Q000494:pharmacology*; D008031:Lignin / Q000031:analogs & derivatives / Q000302:isolation & purification / Q000494:pharmacology*; D051379:Mice; D015394:Molecular Structure; D018547:Plant Stems / Q000737:chemistry; D010974:Platelet Aggregation / Q000187:drug effects; D010975:Platelet Aggregation Inhibitors / Q000737:chemistry / Q000302:isolation & purification / Q000494:pharmacology*; D013237:Stereoisomerism; D013329:Structure-Activity Relationship
chemical_list: D000893:Anti-Inflammatory Agents; D000975:Antioxidants; D016166:Free Radical Scavengers; D010975:Platelet Aggregation Inhibitors; D008031:Lignin