title: Variable-temperature ¹H-NMR studies on two C-glycosylflavones.
abstract: Two known C-glycosylflavones, swertisin and embinoidin, were isolated from the leaves of Anthurium aripoense, and characterized by room temperature 1D and 2D NMR experiments. At this temperature, the ¹H- and ¹³C-NMR spectra of these C-glycosylflavones revealed doubling of signals, which suggested the presence of two rotamers in solution. Variable-temperature (VT) ¹H-NMR studies supported this hypothesis. The T-ROESY data, in addition to the theoretical (MM2) calculations utilizing the Chem3D Pro software, confirmed the hypothesis that the two rotamers interchange via rotation about the C-glycosidic bond.
authors: Department of Chemistry, The University of the West Indies, St. Augustine, Trinidad and Tobago, West Indies.
authors: Julia H
authors: JH
authors: Frank
authors: Yomica L
authors: YL
authors: Powder-George
authors: Russel S
authors: RS
authors: Ramsewak
authors: William F
authors: WF
authors: Reynolds
mesh_terms: D047310:Apigenin / Q000737:chemistry; D047309:Flavones / Q000737:chemistry*; D007536:Isomerism; D009682:Magnetic Resonance Spectroscopy; D008958:Models, Molecular; D011522:Protons; D013696:Temperature
chemical_list: D047309:Flavones; D011522:Protons; C556941:swertisin; D047310:Apigenin