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.
Highlights
Anthurium is a genus of evergreen, climbing or epiphytic herbs which belongs to the Araceae [1], and has reported folkloric uses, which include hallucinogens, insecticides, oral contraceptives, rheumatoid arthritis treatments and skin care agents [2,3,4]
The structures of swertisin (1) and embinoidin (2) were confirmed and spectra assigned by a combination of 1H-1H COSY [11], HSQC [12] and HMBC [13] spectra
The structure of embinoidin (2) is shown in Figure 4, with carbons and the 5-OH proton giving rise to doubled signals marked with asterisks
Summary
Anthurium is a genus of evergreen, climbing or epiphytic herbs which belongs to the Araceae [1], and has reported folkloric uses, which include hallucinogens, insecticides, oral contraceptives, rheumatoid arthritis treatments and skin care agents [2,3,4]. A survey of the literature revealed that there has been no phytochemical investigation of this species. The chemical constituents of this plant were investigated. Two known C-glycosylflavones, swertisin and embinoidin [7], were isolated from the leaves of Anthurium aripoense. Both compounds showed duplication of signals in the 1H- and 13C-NMR spectra at room temperature. For the purpose of this study, steric hindrance proved to be the dominating effect. In this investigation, the structure of the two compounds was confirmed with the aid of 2D NMR experiments while the origin of signal doubling was investigated using variable-temperature (VT).
Sign-in/Register to view highlights & summary Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
