Variable-temperature ¹H-NMR studies on two C-glycosylflavones.

Molecules

Department of Chemistry, The University of the West Indies, St. Augustine, Trinidad and Tobago, West Indies.

Published: July 2012

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.

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http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6268948PMC
http://dx.doi.org/10.3390/molecules17077914DOI Listing

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