title: Polyphenols isolated from antiradical extracts of Mallotus metcalfianus.
abstract: Six flavonoids including two new flavones, luteolin 7-O-(4''-O-(E)-coumaroyl)-beta-glucopyranoside), chrysoeriol-7-O-(4''-O-(E)-coumaroyl)-beta-glucopyranoside) and a mixture of two pairs of diastereoisomeric flavonolignans, (+/-)-hydnocarpin 7-O-(4''-O-(E)-coumaroyl)-beta-glucopyranoside)/(+/-)-hydnocarpin-D 7-O-(4''-O-(E)-coumaroyl)-beta-glucopyranoside) with a 2:1 ratio were isolated from the whole plant of Mallotus metcalfianus Croizat, in addition to 10 known compounds. Their structures were evaluated on the basis of different spectroscopic methods, including extensive 1D and 2D NMR spectroscopy. Some extracts have moderate antimicrobial properties and interesting antiradical (DPPH) activity, as well as some compounds isolated from this species. Tannins were also identified in some active extracts.
authors.affiliation: Université Catholique de Louvain, Louvain Drug Research Institute, CHAM Unit, UCL 7230, Avenue E. Mounier 7, B-1200 Brussels, Belgium.
authors.forename: Céline
authors.initials: C
authors.lastname: Rivière
authors.forename: Van Nguyen Thi
authors.initials: VN
authors.lastname: Hong
authors.forename: Luc
authors.initials: L
authors.lastname: Pieters
authors.forename: Bieke
authors.initials: B
authors.lastname: Dejaegher
authors.forename: Yvan Vander
authors.initials: YV
authors.lastname: Heyden
authors.forename: Minh Chau
authors.initials: MC
authors.lastname: Van
authors.forename: Joëlle
authors.initials: J
authors.lastname: Quetin-Leclercq
mesh_terms: D000900:Anti-Bacterial Agents / Q000737:chemistry / Q000494:pharmacology; D001419:Bacteria / Q000187:drug effects; D005419:Flavonoids / Q000737:chemistry*; D036461:Mallotus Plant / Q000737:chemistry*; D015394:Molecular Structure; D010636:Phenols / Q000737:chemistry*; D010936:Plant Extracts / Q000737:chemistry*; D059808:Polyphenols
chemical_list: D000900:Anti-Bacterial Agents; D005419:Flavonoids; D010636:Phenols; D010936:Plant Extracts; D059808:Polyphenols