title: Antioxidative constituents from the leaves of Hypericum styphelioides.
abstract: Two new compounds have been isolated from the leaves of Hypericum styphelioides. Their structures have been established on the basis of mass spectrometry and 2D NMR techniques as 1,3,5-trihydroxy-2-(2',2'-dimethyl-4'-isopropenyl)cyclopentanylxanthone (1) and 3,5-dihydroxybenzophenon-4-beta-d-glucoside (2). Known compounds 5-O-demethylpaxanthonin (3) and 3-geranyl-1-(3-methylbutanoyl)phloroglucinol (4) were also isolated and characterized. Compounds 1-4 were evaluated for their antioxidative properties in Trolox equivalent antioxidant activity (TEAC) and chemiluminescence (CL) assays.
authors.affiliation: Center of Pharmaceutical Chemistry (CQF), 200 & 21, Atabey, Playa, PO Box 16042, Apartado 6990, La Habana, Cuba.
authors.forename: Daylin
authors.initials: D
authors.lastname: Gamiotea-Turro
authors.forename: Osmany
authors.initials: O
authors.lastname: Cuesta-Rubio
authors.forename: Sylvia
authors.initials: S
authors.lastname: Prieto-González
authors.forename: Francesco
authors.initials: F
authors.lastname: De Simone
authors.forename: Siro
authors.initials: S
authors.lastname: Passi
authors.forename: Luca
authors.initials: L
authors.lastname: Rastrelli
mesh_terms: D000975:Antioxidants / Q000737:chemistry / Q000302:isolation & purification* / Q000494:pharmacology; D001577:Benzophenones / Q000737:chemistry / Q000302:isolation & purification* / Q000494:pharmacology; D003462:Cuba; D005960:Glucosides / Q000737:chemistry / Q000302:isolation & purification* / Q000494:pharmacology; D020902:Hypericum / Q000737:chemistry*; D008163:Luminescent Measurements; D015394:Molecular Structure; D019906:Nuclear Magnetic Resonance, Biomolecular; D010084:Oxidation-Reduction; D018515:Plant Leaves / Q000737:chemistry; D010946:Plants, Medicinal / Q000737:chemistry*; D013237:Stereoisomerism; D044004:Xanthones / Q000737:chemistry / Q000302:isolation & purification* / Q000494:pharmacology
chemical_list: C487243:1,3,5-trihydroxy-2-(2',2'-dimethyl-4'-isopropenyl)cyclopentanylxanthone; C487244:3,5-dihydroxybenzophenon-4-glucoside; D000975:Antioxidants; D001577:Benzophenones; D005960:Glucosides; D044004:Xanthones