Submitted to: Archives for Organic Chemistry (ARKIVOC)
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 4/20/2014
Publication Date: 6/22/2014
Citation: Franz, A.H., Serebnitskaya, L., Gudial, G., Wallis, C.M. 2014. Structure assignment and H/D-exchange behavior of several glycosylated polyphenols. Archives for Organic Chemistry (ARKIVOC). 2014:94-122. Interpretive Summary: Polyphenols are important for both the plants that produce them and human health. However, knowledge about the three-dimensional structure of polyphenols is needed to understand how these compounds function and to optimize artificial synthesis. Nuclear magnetic resonance was used to elucidate the structures of representative polyphenols resveratrol, (-)-epicatechin, pelargonidine chloride, cyanidine chloride, cyanine chloride, and keracyanine chloride. Identification of the structures of these six polyphenols may facilitate functional analysis research and allow synthetic manufacturing to proceed.
Technical Abstract: Polyphenols are plant-produced compounds that are produced for a variety of reasons, such as acting as pigments, limiting herbivory, combating pathogens, and protection from abiotic stresses. Likewise, polyphenols have been considered beneficial to human health, with beneficial effects against hypertension, atherosclerosis, diabetes, and stroke. However, investigations into how polyphenols work at molecular levels are hampered by lack of comprehensive three-dimensional structures. Synthetic manufacturing also could benefit through knowledge of polyphenol structures. Therefore, nuclear magnetic resonance (NMR) was used to elucidate structures of six polyphenols: resveratrol, (-)-epicatechin, pelargonidine chloride, cyanidine chloride, cyanine chloride, and keracyanine chloride. Further, it was observed that a selective HCl-catalyzed H/D-exchange occurred for aromatic protons H6 and H8 in pelargonidine chloride, cyanidine chloride, and keracyanidine chloride. These results facilitate studies that determine how polyphenols function. Knowledge of the structures also may aid in developing synthetic manufacture of these beneficial polyphenols.