title: Two new antioxidant bergenin derivatives from the stem of Rivea hypocrateriformis.
abstract: Two new bergenin derivatives, named rivebergenin A and B (1, and 2), together with two known compounds, bergenin (3) and norbergenin (4) were isolated from the stem of Rivea hypocrateriformis (Desr.) Choisy. The structures of the new compound have been assigned from (1)H and (13)C NMR spectra, DEPT, and by 2D COSY, HMQC, and HMBC experiments. Compounds 1-4 showed the strong antioxidant activity.
authors.affiliation: Department of Botany, University of Karachi, Karachi-75270, Pakistan.
authors.lastname: Zamarrud
authors.forename: Iftikhar
authors.initials: I
authors.lastname: Ali
authors.forename: Hidayat
authors.initials: H
authors.lastname: Hussain
authors.forename: Viqar Uddin
authors.initials: VU
authors.lastname: Ahmad
authors.forename: Muhammad
authors.initials: M
authors.lastname: Qaiser
authors.forename: Afroze
authors.initials: A
authors.lastname: Amyn
authors.forename: Faryal Vali
authors.initials: FV
authors.lastname: Mohammad
mesh_terms: D000975:Antioxidants / Q000302:isolation & purification*; D001578:Benzopyrans / Q000737:chemistry / Q000302:isolation & purification*; D027722:Convolvulaceae / Q000737:chemistry*; D015394:Molecular Structure; D018547:Plant Stems / Q000737:chemistry; D010946:Plants, Medicinal / Q000737:chemistry
chemical_list: D000975:Antioxidants; D001578:Benzopyrans; C560511:rivebergenin A; C560512:rivebergenin B; C006741:bergenin