title: Dihydrochalcones and flavonolignans from Iryanthera lancifolia.
abstract: An extract from the pericarps of I. lancifolia afforded two dihydrochalcones (1 and 2) and two flavonolignans (3 and 4), with compounds 2-4 being of novel structure. The antioxidant activities of compounds 1-4 were evaluated through the measurement of malondialdehyde production, and Q(1/2) (concentration necessary for 50% inhibition of autoxidation) data were calculated. The Q(1/2) values obtained for 1-4 and the standard compounds alpha-tocopherol and quercetin were 6.9, 4.7, 5.5, 4.8, 12.1, and 7.6 microg/mL, respectively.
authors.affiliation: Instituto de Qu¿imica, Universidade de Såo Paulo, C.P. 26077, CEP 05599-970, Såo Paulo-SP, Brazil, Instituto de Qu¿imica, Universidade Estadual Paulista, C.P. 355, CEP 14800-900, Araraquara-SP, Brazil, and Faculdade de Ci¿enc. dhsilva@iq.unesp.br
authors.forename: D H
authors.initials: DH
authors.lastname: Silva
authors.forename: S C
authors.initials: SC
authors.lastname: Davino
authors.forename: S B
authors.initials: SB
authors.lastname: Barros
authors.forename: M
authors.initials: M
authors.lastname: Yoshida
mesh_terms: D000818:Animals; D000975:Antioxidants / Q000737:chemistry* / Q000494:pharmacology; D001923:Brain Chemistry / Q000187:drug effects; D001938:Brazil; D002240:Carbohydrate Sequence; D002599:Chalcone / Q000031:analogs & derivatives / Q000737:chemistry* / Q000494:pharmacology; D005419:Flavonoids / Q000737:chemistry* / Q000494:pharmacology; D017705:Lignans / Q000737:chemistry* / Q000494:pharmacology; D009682:Magnetic Resonance Spectroscopy; D008969:Molecular Sequence Data; D010946:Plants, Medicinal / Q000737:chemistry*; D051381:Rats; D013055:Spectrophotometry, Infrared; D013056:Spectrophotometry, Ultraviolet; D017392:Thiobarbituric Acid Reactive Substances / Q000737:chemistry
chemical_list: D000975:Antioxidants; D005419:Flavonoids; D017705:Lignans; D017392:Thiobarbituric Acid Reactive Substances; D002599:Chalcone