title: (+)-Kunstlerone, a new antioxidant neolignan from the Leaves of Beilschmiedia kunstleri gamble.
abstract: A new neolignan, 3,4-dimethoxy-3',4'-methylenedioxy-2,9-epoxy-6,7-cyclo-1,8-neolign-11-en-5(5H)-one, which has been named (+)-kunstlerone (1), together with six known alkaloids: (+)-norboldine (2), (+)-N-methylisococlaurine (3), (+)-cassythicine (4), (+)-laurotetanine (5), (+)-boldine (6) and (-)-pallidine (7), were isolated from the leaves of Beilschmiedia kunstleri. The structures were established through various spectroscopic methods notably 1D- and 2D-NMR, UV, IR and LCMS-IT-TOF. (+)- Kunstlerone (1) showed a strong antioxidant activity, with an SC(50) of 20.0 µg/mL.
authors.affiliation: Department of Chemistry, Faculty of Science, University of Malaya, 50603 Kuala Lumpur, Malaysia. abbas@siswa.um.edu.my
authors.forename: Abbas
authors.initials: A
authors.lastname: Mollataghi
authors.forename: A Hamid A
authors.initials: AH
authors.lastname: Hadi
authors.forename: Khalijah
authors.initials: K
authors.lastname: Awang
authors.forename: Jamaludin
authors.initials: J
authors.lastname: Mohamad
authors.forename: Marc
authors.initials: M
authors.lastname: Litaudon
authors.forename: Mat Ropi
authors.initials: MR
authors.lastname: Mukhtar
mesh_terms: D000470:Alkaloids / Q000737:chemistry / Q000302:isolation & purification* / Q000494:pharmacology; D000975:Antioxidants / Q000737:chemistry / Q000302:isolation & purification* / Q000494:pharmacology; D001205:Ascorbic Acid / Q000494:pharmacology; D001713:Biphenyl Compounds / Q000037:antagonists & inhibitors / Q000378:metabolism; D002626:Chemistry, Pharmaceutical / Q000379:methods*; D002853:Chromatography, Liquid; D005609:Free Radicals / Q000037:antagonists & inhibitors / Q000378:metabolism; D019770:Lauraceae / Q000737:chemistry*; D017705:Lignans / Q000737:chemistry / Q000302:isolation & purification* / Q000494:pharmacology; D009682:Magnetic Resonance Spectroscopy; D008296:Malaysia; D013058:Mass Spectrometry; D008958:Models, Molecular; D010851:Picrates / Q000037:antagonists & inhibitors / Q000378:metabolism; D018515:Plant Leaves / Q000737:chemistry*
chemical_list: D000470:Alkaloids; D000975:Antioxidants; D001713:Biphenyl Compounds; D005609:Free Radicals; D017705:Lignans; D010851:Picrates; C004931:1,1-diphenyl-2-picrylhydrazyl; D001205:Ascorbic Acid